summaryrefslogtreecommitdiff
path: root/macros/luatex/generic/penlight/penlight.lua
blob: 4b2436be1b3eaf5ca1e1aa442d48ad7659504d97 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530
3531
3532
3533
3534
3535
3536
3537
3538
3539
3540
3541
3542
3543
3544
3545
3546
3547
3548
3549
3550
3551
3552
3553
3554
3555
3556
3557
3558
3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585
3586
3587
3588
3589
3590
3591
3592
3593
3594
3595
3596
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
3621
3622
3623
3624
3625
3626
3627
3628
3629
3630
3631
3632
3633
3634
3635
3636
3637
3638
3639
3640
3641
3642
3643
3644
3645
3646
3647
3648
3649
3650
3651
3652
3653
3654
3655
3656
3657
3658
3659
3660
3661
3662
3663
3664
3665
3666
3667
3668
3669
3670
3671
3672
3673
3674
3675
3676
3677
3678
3679
3680
3681
3682
3683
3684
3685
3686
3687
3688
3689
3690
3691
3692
3693
3694
3695
3696
3697
3698
3699
3700
3701
3702
3703
3704
3705
3706
3707
3708
3709
3710
3711
3712
3713
3714
3715
3716
3717
3718
3719
3720
3721
3722
3723
3724
3725
3726
3727
3728
3729
3730
3731
3732
3733
3734
3735
3736
3737
3738
3739
3740
3741
3742
3743
3744
3745
3746
3747
3748
3749
3750
3751
3752
3753
3754
3755
3756
3757
3758
3759
3760
3761
3762
3763
3764
3765
3766
3767
3768
3769
3770
3771
3772
3773
3774
3775
3776
3777
3778
3779
3780
3781
3782
3783
3784
3785
3786
3787
3788
3789
3790
3791
3792
3793
3794
3795
3796
3797
3798
3799
3800
3801
3802
3803
3804
3805
3806
3807
3808
3809
3810
3811
3812
3813
3814
3815
3816
3817
3818
3819
3820
3821
3822
3823
3824
3825
3826
3827
3828
3829
3830
3831
3832
3833
3834
3835
3836
3837
3838
3839
3840
3841
3842
3843
3844
3845
3846
3847
3848
3849
3850
3851
3852
3853
3854
3855
3856
3857
3858
3859
3860
3861
3862
3863
3864
3865
3866
3867
3868
3869
3870
3871
3872
3873
3874
3875
3876
3877
3878
3879
3880
3881
3882
3883
3884
3885
3886
3887
3888
3889
3890
3891
3892
3893
3894
3895
3896
3897
3898
3899
3900
3901
3902
3903
3904
3905
3906
3907
3908
3909
3910
3911
3912
3913
3914
3915
3916
3917
3918
3919
3920
3921
3922
3923
3924
3925
3926
3927
3928
3929
3930
3931
3932
3933
3934
3935
3936
3937
3938
3939
3940
3941
3942
3943
3944
3945
3946
3947
3948
3949
3950
3951
3952
3953
3954
3955
3956
3957
3958
3959
3960
3961
3962
3963
3964
3965
3966
3967
3968
3969
3970
3971
3972
3973
3974
3975
3976
3977
3978
3979
3980
3981
3982
3983
3984
3985
3986
3987
3988
3989
3990
3991
3992
3993
3994
3995
3996
3997
3998
3999
4000
4001
4002
4003
4004
4005
4006
4007
4008
4009
4010
4011
4012
4013
4014
4015
4016
4017
4018
4019
4020
4021
4022
4023
4024
4025
4026
4027
4028
4029
4030
4031
4032
4033
4034
4035
4036
4037
4038
4039
4040
4041
4042
4043
4044
4045
4046
4047
4048
4049
4050
4051
4052
4053
4054
4055
4056
4057
4058
4059
4060
4061
4062
4063
4064
4065
4066
4067
4068
4069
4070
4071
4072
4073
4074
4075
4076
4077
4078
4079
4080
4081
4082
4083
4084
4085
4086
4087
4088
4089
4090
4091
4092
4093
4094
4095
4096
4097
4098
4099
4100
4101
4102
4103
4104
4105
4106
4107
4108
4109
4110
4111
4112
4113
4114
4115
4116
4117
4118
4119
4120
4121
4122
4123
4124
4125
4126
4127
4128
4129
4130
4131
4132
4133
4134
4135
4136
4137
4138
4139
4140
4141
4142
4143
4144
4145
4146
4147
4148
4149
4150
4151
4152
4153
4154
4155
4156
4157
4158
4159
4160
4161
4162
4163
4164
4165
4166
4167
4168
4169
4170
4171
4172
4173
4174
4175
4176
4177
4178
4179
4180
4181
4182
4183
4184
4185
4186
4187
4188
4189
4190
4191
4192
4193
4194
4195
4196
4197
4198
4199
4200
4201
4202
4203
4204
4205
4206
4207
4208
4209
4210
4211
4212
4213
4214
4215
4216
4217
4218
4219
4220
4221
4222
4223
4224
4225
4226
4227
4228
4229
4230
4231
4232
4233
4234
4235
4236
4237
4238
4239
4240
4241
4242
4243
4244
4245
4246
4247
4248
4249
4250
4251
4252
4253
4254
4255
4256
4257
4258
4259
4260
4261
4262
4263
4264
4265
4266
4267
4268
4269
4270
4271
4272
4273
4274
4275
4276
4277
4278
4279
4280
4281
4282
4283
4284
4285
4286
4287
4288
4289
4290
4291
4292
4293
4294
4295
4296
4297
4298
4299
4300
4301
4302
4303
4304
4305
4306
4307
4308
4309
4310
4311
4312
4313
4314
4315
4316
4317
4318
4319
4320
4321
4322
4323
4324
4325
4326
4327
4328
4329
4330
4331
4332
4333
4334
4335
4336
4337
4338
4339
4340
4341
4342
4343
4344
4345
4346
4347
4348
4349
4350
4351
4352
4353
4354
4355
4356
4357
4358
4359
4360
4361
4362
4363
4364
4365
4366
4367
4368
4369
4370
4371
4372
4373
4374
4375
4376
4377
4378
4379
4380
4381
4382
4383
4384
4385
4386
4387
4388
4389
4390
4391
4392
4393
4394
4395
4396
4397
4398
4399
4400
4401
4402
4403
4404
4405
4406
4407
4408
4409
4410
4411
4412
4413
4414
4415
4416
4417
4418
4419
4420
4421
4422
4423
4424
4425
4426
4427
4428
4429
4430
4431
4432
4433
4434
4435
4436
4437
4438
4439
4440
4441
4442
4443
4444
4445
4446
4447
4448
4449
4450
4451
4452
4453
4454
4455
4456
4457
4458
4459
4460
4461
4462
4463
4464
4465
4466
4467
4468
4469
4470
4471
4472
4473
4474
4475
4476
4477
4478
4479
4480
4481
4482
4483
4484
4485
4486
4487
4488
4489
4490
4491
4492
4493
4494
4495
4496
4497
4498
4499
4500
4501
4502
4503
4504
4505
4506
4507
4508
4509
4510
4511
4512
4513
4514
4515
4516
4517
4518
4519
4520
4521
4522
4523
4524
4525
4526
4527
4528
4529
4530
4531
4532
4533
4534
4535
4536
4537
4538
4539
4540
4541
4542
4543
4544
4545
4546
4547
4548
4549
4550
4551
4552
4553
4554
4555
4556
4557
4558
4559
4560
4561
4562
4563
4564
4565
4566
4567
4568
4569
4570
4571
4572
4573
4574
4575
4576
4577
4578
4579
4580
4581
4582
4583
4584
4585
4586
4587
4588
4589
4590
4591
4592
4593
4594
4595
4596
4597
4598
4599
4600
4601
4602
4603
4604
4605
4606
4607
4608
4609
4610
4611
4612
4613
4614
4615
4616
4617
4618
4619
4620
4621
4622
4623
4624
4625
4626
4627
4628
4629
4630
4631
4632
4633
4634
4635
4636
4637
4638
4639
4640
4641
4642
4643
4644
4645
4646
4647
4648
4649
4650
4651
4652
4653
4654
4655
4656
4657
4658
4659
4660
4661
4662
4663
4664
4665
4666
4667
4668
4669
4670
4671
4672
4673
4674
4675
4676
4677
4678
4679
4680
4681
4682
4683
4684
4685
4686
4687
4688
4689
4690
4691
4692
4693
4694
4695
4696
4697
4698
4699
4700
4701
4702
4703
4704
4705
4706
4707
4708
4709
4710
4711
4712
4713
4714
4715
4716
4717
4718
4719
4720
4721
4722
4723
4724
4725
4726
4727
4728
4729
4730
4731
4732
4733
4734
4735
4736
4737
4738
4739
4740
4741
4742
4743
4744
4745
4746
4747
4748
4749
4750
4751
4752
4753
4754
4755
4756
4757
4758
4759
4760
4761
4762
4763
4764
4765
4766
4767
4768
4769
4770
4771
4772
4773
4774
4775
4776
4777
4778
4779
4780
4781
4782
4783
4784
4785
4786
4787
4788
4789
4790
4791
4792
4793
4794
4795
4796
4797
4798
4799
4800
4801
4802
4803
4804
4805
4806
4807
4808
4809
4810
4811
4812
4813
4814
4815
4816
4817
4818
4819
4820
4821
4822
4823
4824
4825
4826
4827
4828
4829
4830
4831
4832
4833
4834
4835
4836
4837
4838
4839
4840
4841
4842
4843
4844
4845
4846
4847
4848
4849
4850
4851
4852
4853
4854
4855
4856
4857
4858
4859
4860
4861
4862
4863
4864
4865
4866
4867
4868
4869
4870
4871
4872
4873
4874
4875
4876
4877
4878
4879
4880
4881
4882
4883
4884
4885
4886
4887
4888
4889
4890
4891
4892
4893
4894
4895
4896
4897
4898
4899
4900
4901
4902
4903
4904
4905
4906
4907
4908
4909
4910
4911
4912
4913
4914
4915
4916
4917
4918
4919
4920
4921
4922
4923
4924
4925
4926
4927
4928
4929
4930
4931
4932
4933
4934
4935
4936
4937
4938
4939
4940
4941
4942
4943
4944
4945
4946
4947
4948
4949
4950
4951
4952
4953
4954
4955
4956
4957
4958
4959
4960
4961
4962
4963
4964
4965
4966
4967
4968
4969
4970
4971
4972
4973
4974
4975
4976
4977
4978
4979
4980
4981
4982
4983
4984
4985
4986
4987
4988
4989
4990
4991
4992
4993
4994
4995
4996
4997
4998
4999
5000
5001
5002
5003
5004
5005
5006
5007
5008
5009
5010
5011
5012
5013
5014
5015
5016
5017
5018
5019
5020
5021
5022
5023
5024
5025
5026
5027
5028
5029
5030
5031
5032
5033
5034
5035
5036
5037
5038
5039
5040
5041
5042
5043
5044
5045
5046
5047
5048
5049
5050
5051
5052
5053
5054
5055
5056
5057
5058
5059
5060
5061
5062
5063
5064
5065
5066
5067
5068
5069
5070
5071
5072
5073
5074
5075
5076
5077
5078
5079
5080
5081
5082
5083
5084
5085
5086
5087
5088
5089
5090
5091
5092
5093
5094
5095
5096
5097
5098
5099
5100
5101
5102
5103
5104
5105
5106
5107
5108
5109
5110
5111
5112
5113
5114
5115
5116
5117
5118
5119
5120
5121
5122
5123
5124
5125
5126
5127
5128
5129
5130
5131
5132
5133
5134
5135
5136
5137
5138
5139
5140
5141
5142
5143
5144
5145
5146
5147
5148
5149
5150
5151
5152
5153
5154
5155
5156
5157
5158
5159
5160
5161
5162
5163
5164
5165
5166
5167
5168
5169
5170
5171
5172
5173
5174
5175
5176
5177
5178
5179
5180
5181
5182
5183
5184
5185
5186
5187
5188
5189
5190
5191
5192
5193
5194
5195
5196
5197
5198
5199
5200
5201
5202
5203
5204
5205
5206
5207
5208
5209
5210
5211
5212
5213
5214
5215
5216
5217
5218
5219
5220
5221
5222
5223
5224
5225
5226
5227
5228
5229
5230
5231
5232
5233
5234
5235
5236
5237
5238
5239
5240
5241
5242
5243
5244
5245
5246
5247
5248
5249
5250
5251
5252
5253
5254
5255
5256
5257
5258
5259
5260
5261
5262
5263
5264
5265
5266
5267
5268
5269
5270
5271
5272
5273
5274
5275
5276
5277
5278
5279
5280
5281
5282
5283
5284
5285
5286
5287
5288
5289
5290
5291
5292
5293
5294
5295
5296
5297
5298
5299
5300
5301
5302
5303
5304
5305
5306
5307
5308
5309
5310
5311
5312
5313
5314
5315
5316
5317
5318
5319
5320
5321
5322
5323
5324
5325
5326
5327
5328
5329
5330
5331
5332
5333
5334
5335
5336
5337
5338
5339
5340
5341
5342
5343
5344
5345
5346
5347
5348
5349
5350
5351
5352
5353
5354
5355
5356
5357
5358
5359
5360
5361
5362
5363
5364
5365
5366
5367
5368
5369
5370
5371
5372
5373
5374
5375
5376
5377
5378
5379
5380
5381
5382
5383
5384
5385
5386
5387
5388
5389
5390
5391
5392
5393
5394
5395
5396
5397
5398
5399
5400
5401
5402
5403
5404
5405
5406
5407
5408
5409
5410
5411
5412
5413
5414
5415
5416
5417
5418
5419
5420
5421
5422
5423
5424
5425
5426
5427
5428
5429
5430
5431
5432
5433
5434
5435
5436
5437
5438
5439
5440
5441
5442
5443
5444
5445
5446
5447
5448
5449
5450
5451
5452
5453
5454
5455
5456
5457
5458
5459
5460
5461
5462
5463
5464
5465
5466
5467
5468
5469
5470
5471
5472
5473
5474
5475
5476
5477
5478
5479
5480
5481
5482
5483
5484
5485
5486
5487
5488
5489
5490
5491
5492
5493
5494
5495
5496
5497
5498
5499
5500
5501
5502
5503
5504
5505
5506
5507
5508
5509
5510
5511
5512
5513
5514
5515
5516
5517
5518
5519
5520
5521
5522
5523
5524
5525
5526
5527
5528
5529
5530
5531
5532
5533
5534
5535
5536
5537
5538
5539
5540
5541
5542
5543
5544
5545
5546
5547
5548
5549
5550
5551
5552
5553
5554
5555
5556
5557
5558
5559
5560
5561
5562
5563
5564
5565
5566
5567
5568
5569
5570
5571
5572
5573
5574
5575
5576
5577
5578
5579
5580
5581
5582
5583
5584
5585
5586
5587
5588
5589
5590
5591
5592
5593
5594
5595
5596
5597
5598
5599
5600
5601
5602
5603
5604
5605
5606
5607
5608
5609
5610
5611
5612
5613
5614
5615
5616
5617
5618
5619
5620
5621
5622
5623
5624
5625
5626
5627
5628
5629
5630
5631
5632
5633
5634
5635
5636
5637
5638
5639
5640
5641
5642
5643
5644
5645
5646
5647
5648
5649
5650
5651
5652
5653
5654
5655
5656
5657
5658
5659
5660
5661
5662
5663
5664
5665
5666
5667
5668
5669
5670
5671
5672
5673
5674
5675
5676
5677
5678
5679
5680
5681
5682
5683
5684
5685
5686
5687
5688
5689
5690
5691
5692
5693
5694
5695
5696
5697
5698
5699
5700
5701
5702
5703
5704
5705
5706
5707
5708
5709
5710
5711
5712
5713
5714
5715
5716
5717
5718
5719
5720
5721
5722
5723
5724
5725
5726
5727
5728
5729
5730
5731
5732
5733
5734
5735
5736
5737
5738
5739
5740
5741
5742
5743
5744
5745
5746
5747
5748
5749
5750
5751
5752
5753
5754
5755
5756
5757
5758
5759
5760
5761
5762
5763
5764
5765
5766
5767
5768
5769
5770
5771
5772
5773
5774
5775
5776
5777
5778
5779
5780
5781
5782
5783
5784
5785
5786
5787
5788
5789
5790
5791
5792
5793
5794
5795
5796
5797
5798
5799
5800
5801
5802
5803
5804
5805
5806
5807
5808
5809
5810
5811
5812
5813
5814
5815
5816
5817
5818
5819
5820
5821
5822
5823
5824
5825
5826
5827
5828
5829
5830
5831
5832
5833
5834
5835
5836
5837
5838
5839
5840
5841
5842
5843
5844
5845
5846
5847
5848
5849
5850
5851
5852
5853
5854
5855
5856
5857
5858
5859
5860
5861
5862
5863
5864
5865
5866
5867
5868
5869
5870
5871
5872
5873
5874
5875
5876
5877
5878
5879
5880
5881
5882
5883
5884
5885
5886
5887
5888
5889
5890
5891
5892
5893
5894
5895
5896
5897
5898
5899
5900
5901
5902
5903
5904
5905
5906
5907
5908
5909
5910
5911
5912
5913
5914
5915
5916
5917
5918
5919
5920
5921
5922
5923
5924
5925
5926
5927
5928
5929
5930
5931
5932
5933
5934
5935
5936
5937
5938
5939
5940
5941
5942
5943
5944
5945
5946
5947
5948
5949
5950
5951
5952
5953
5954
5955
5956
5957
5958
5959
5960
5961
5962
5963
5964
5965
5966
5967
5968
5969
5970
5971
5972
5973
5974
5975
5976
5977
5978
5979
5980
5981
5982
5983
5984
5985
5986
5987
5988
5989
5990
5991
5992
5993
5994
5995
5996
5997
5998
5999
6000
6001
6002
6003
6004
6005
6006
6007
6008
6009
6010
6011
6012
6013
6014
6015
6016
6017
6018
6019
6020
6021
6022
6023
6024
6025
6026
6027
6028
6029
6030
6031
6032
6033
6034
6035
6036
6037
6038
6039
6040
6041
6042
6043
6044
6045
6046
6047
6048
6049
6050
6051
6052
6053
6054
6055
6056
6057
6058
6059
6060
6061
6062
6063
6064
6065
6066
6067
6068
6069
6070
6071
6072
6073
6074
6075
6076
6077
6078
6079
6080
6081
6082
6083
6084
6085
6086
6087
6088
6089
6090
6091
6092
6093
6094
6095
6096
6097
6098
6099
6100
6101
6102
6103
6104
6105
6106
6107
6108
6109
6110
6111
6112
6113
6114
6115
6116
6117
6118
6119
6120
6121
6122
6123
6124
6125
6126
6127
6128
6129
6130
6131
6132
6133
6134
6135
6136
6137
6138
6139
6140
6141
6142
6143
6144
6145
6146
6147
6148
6149
6150
6151
6152
6153
6154
6155
6156
6157
6158
6159
6160
6161
6162
6163
6164
6165
6166
6167
6168
6169
6170
6171
6172
6173
6174
6175
6176
6177
6178
6179
6180
6181
6182
6183
6184
6185
6186
6187
6188
6189
6190
6191
6192
6193
6194
6195
6196
6197
6198
6199
6200
6201
6202
6203
6204
6205
6206
6207
6208
6209
6210
6211
6212
6213
6214
6215
6216
6217
6218
6219
6220
6221
6222
6223
6224
6225
6226
6227
6228
6229
6230
6231
6232
6233
6234
6235
6236
6237
6238
6239
6240
6241
6242
6243
6244
6245
6246
6247
6248
6249
6250
6251
6252
6253
6254
6255
6256
6257
6258
6259
6260
6261
6262
6263
6264
6265
6266
6267
6268
6269
6270
6271
6272
6273
6274
6275
6276
6277
6278
6279
6280
6281
6282
6283
6284
6285
6286
6287
6288
6289
6290
6291
6292
6293
6294
6295
6296
6297
6298
6299
6300
6301
6302
6303
6304
6305
6306
6307
6308
6309
6310
6311
6312
6313
6314
6315
6316
6317
6318
6319
6320
6321
6322
6323
6324
6325
6326
6327
6328
6329
6330
6331
6332
6333
6334
6335
6336
6337
6338
6339
6340
6341
6342
6343
6344
6345
6346
6347
6348
6349
6350
6351
6352
6353
6354
6355
6356
6357
6358
6359
6360
6361
6362
6363
6364
6365
6366
6367
6368
6369
6370
6371
6372
6373
6374
6375
6376
6377
6378
6379
6380
6381
6382
6383
6384
6385
6386
6387
6388
6389
6390
6391
6392
6393
6394
6395
6396
6397
6398
6399
6400
6401
6402
6403
6404
6405
6406
6407
6408
6409
6410
6411
6412
6413
6414
6415
6416
6417
6418
6419
6420
6421
6422
6423
6424
6425
6426
6427
6428
6429
6430
6431
6432
6433
6434
6435
6436
6437
6438
6439
6440
6441
6442
6443
6444
6445
6446
6447
6448
6449
6450
6451
6452
6453
6454
6455
6456
6457
6458
6459
6460
6461
6462
6463
6464
6465
6466
6467
6468
6469
6470
6471
6472
6473
6474
6475
6476
6477
6478
6479
6480
6481
6482
6483
6484
6485
6486
6487
6488
6489
6490
6491
6492
6493
6494
6495
6496
6497
6498
6499
6500
6501
6502
6503
6504
6505
6506
6507
6508
6509
6510
6511
6512
6513
6514
6515
6516
6517
6518
6519
6520
6521
6522
6523
6524
6525
6526
6527
6528
6529
6530
6531
6532
6533
6534
6535
6536
6537
6538
6539
6540
6541
6542
6543
6544
6545
6546
6547
6548
6549
6550
6551
6552
6553
6554
6555
6556
6557
6558
6559
6560
6561
6562
6563
6564
6565
6566
6567
6568
6569
6570
6571
6572
6573
6574
6575
6576
6577
6578
6579
6580
6581
6582
6583
6584
6585
6586
6587
6588
6589
6590
6591
6592
6593
6594
6595
6596
6597
6598
6599
6600
6601
6602
6603
6604
6605
6606
6607
6608
6609
6610
6611
6612
6613
6614
6615
6616
6617
6618
6619
6620
6621
6622
6623
6624
6625
6626
6627
6628
6629
6630
6631
6632
6633
6634
6635
6636
6637
6638
6639
6640
6641
6642
6643
6644
6645
6646
6647
6648
6649
6650
6651
6652
6653
6654
6655
6656
6657
6658
6659
6660
6661
6662
6663
6664
6665
6666
6667
6668
6669
6670
6671
6672
6673
6674
6675
6676
6677
6678
6679
6680
6681
6682
6683
6684
6685
6686
6687
6688
6689
6690
6691
6692
6693
6694
6695
6696
6697
6698
6699
6700
6701
6702
6703
6704
6705
6706
6707
6708
6709
6710
6711
6712
6713
6714
6715
6716
6717
6718
6719
6720
6721
6722
6723
6724
6725
6726
6727
6728
6729
6730
6731
6732
6733
6734
6735
6736
6737
6738
6739
6740
6741
6742
6743
6744
6745
6746
6747
6748
6749
6750
6751
6752
6753
6754
6755
6756
6757
6758
6759
6760
6761
6762
6763
6764
6765
6766
6767
6768
6769
6770
6771
6772
6773
6774
6775
6776
6777
6778
6779
6780
6781
6782
6783
6784
6785
6786
6787
6788
6789
6790
6791
6792
6793
6794
6795
6796
6797
6798
6799
6800
6801
6802
6803
6804
6805
6806
6807
6808
6809
6810
6811
6812
6813
6814
6815
6816
6817
6818
6819
6820
6821
6822
6823
6824
6825
6826
6827
6828
6829
6830
6831
6832
6833
6834
6835
6836
6837
6838
6839
6840
6841
6842
6843
6844
6845
6846
6847
6848
6849
6850
6851
6852
6853
6854
6855
6856
6857
6858
6859
6860
6861
6862
6863
6864
6865
6866
6867
6868
6869
6870
6871
6872
6873
6874
6875
6876
6877
6878
6879
6880
6881
6882
6883
6884
6885
6886
6887
6888
6889
6890
6891
6892
6893
6894
6895
6896
6897
6898
6899
6900
6901
6902
6903
6904
6905
6906
6907
6908
6909
6910
6911
6912
6913
6914
6915
6916
6917
6918
6919
6920
6921
6922
6923
6924
6925
6926
6927
6928
6929
6930
6931
6932
6933
6934
6935
6936
6937
6938
6939
6940
6941
6942
6943
6944
6945
6946
6947
6948
6949
6950
6951
6952
6953
6954
6955
6956
6957
6958
6959
6960
6961
6962
6963
6964
6965
6966
6967
6968
6969
6970
6971
6972
6973
6974
6975
6976
6977
6978
6979
6980
6981
6982
6983
6984
6985
6986
6987
6988
6989
6990
6991
6992
6993
6994
6995
6996
6997
6998
6999
7000
7001
7002
7003
7004
7005
7006
7007
7008
7009
7010
7011
7012
7013
7014
7015
7016
7017
7018
7019
7020
7021
7022
7023
7024
7025
7026
7027
7028
7029
7030
7031
7032
7033
7034
7035
7036
7037
7038
7039
7040
7041
7042
7043
7044
7045
7046
7047
7048
7049
7050
7051
7052
7053
7054
7055
7056
7057
7058
7059
7060
7061
7062
7063
7064
7065
7066
7067
7068
7069
7070
7071
7072
7073
7074
7075
7076
7077
7078
7079
7080
7081
7082
7083
7084
7085
7086
7087
7088
7089
7090
7091
7092
7093
7094
7095
7096
7097
7098
7099
7100
7101
7102
7103
7104
7105
7106
7107
7108
7109
7110
7111
7112
7113
7114
7115
7116
7117
7118
7119
7120
7121
7122
7123
7124
7125
7126
7127
7128
7129
7130
7131
7132
7133
7134
7135
7136
7137
7138
7139
7140
7141
7142
7143
7144
7145
7146
7147
7148
7149
7150
7151
7152
7153
7154
7155
7156
7157
7158
7159
7160
7161
7162
7163
7164
7165
7166
7167
7168
7169
7170
7171
7172
7173
7174
7175
7176
7177
7178
7179
7180
7181
7182
7183
7184
7185
7186
7187
7188
7189
7190
7191
7192
7193
7194
7195
7196
7197
7198
7199
7200
7201
7202
7203
7204
7205
7206
7207
7208
7209
7210
7211
7212
7213
7214
7215
7216
7217
7218
7219
7220
7221
7222
7223
7224
7225
7226
7227
7228
7229
7230
7231
7232
7233
7234
7235
7236
7237
7238
7239
7240
7241
7242
7243
7244
7245
7246
7247
7248
7249
7250
7251
7252
7253
7254
7255
7256
7257
7258
7259
7260
7261
7262
7263
7264
7265
7266
7267
7268
7269
7270
7271
7272
7273
7274
7275
7276
7277
7278
7279
7280
7281
7282
7283
7284
7285
7286
7287
7288
7289
7290
7291
7292
7293
7294
7295
7296
7297
7298
7299
7300
7301
7302
7303
7304
7305
7306
7307
7308
7309
7310
7311
7312
7313
7314
7315
7316
7317
7318
7319
7320
7321
7322
7323
7324
7325
7326
7327
7328
7329
7330
7331
7332
7333
7334
7335
7336
7337
7338
7339
7340
7341
7342
7343
7344
7345
7346
7347
7348
7349
7350
7351
7352
7353
7354
7355
7356
7357
7358
7359
7360
7361
7362
7363
7364
7365
7366
7367
7368
7369
7370
7371
7372
7373
7374
7375
7376
7377
7378
7379
7380
7381
7382
7383
7384
7385
7386
7387
7388
7389
7390
7391
7392
7393
7394
7395
7396
7397
7398
7399
7400
7401
7402
7403
7404
7405
7406
7407
7408
7409
7410
7411
7412
7413
7414
7415
7416
7417
7418
7419
7420
7421
7422
7423
7424
7425
7426
7427
7428
7429
7430
7431
7432
7433
7434
7435
7436
7437
7438
7439
7440
7441
7442
7443
7444
7445
7446
7447
7448
7449
7450
7451
7452
7453
7454
7455
7456
7457
7458
7459
7460
7461
7462
7463
7464
7465
7466
7467
7468
7469
7470
7471
7472
7473
7474
7475
7476
7477
7478
7479
7480
7481
7482
7483
7484
7485
7486
7487
7488
7489
7490
7491
7492
7493
7494
7495
7496
7497
7498
7499
7500
7501
7502
7503
7504
7505
7506
7507
7508
7509
7510
7511
7512
7513
7514
7515
7516
7517
7518
7519
7520
7521
7522
7523
7524
7525
7526
7527
7528
7529
7530
7531
7532
7533
7534
7535
7536
7537
7538
7539
7540
7541
7542
7543
7544
7545
7546
7547
7548
7549
7550
7551
7552
7553
7554
7555
7556
7557
7558
7559
7560
7561
7562
7563
7564
7565
7566
7567
7568
7569
7570
7571
7572
7573
7574
7575
7576
7577
7578
7579
7580
7581
7582
7583
7584
7585
7586
7587
7588
7589
7590
7591
7592
7593
7594
7595
7596
7597
7598
7599
7600
7601
7602
7603
7604
7605
7606
7607
7608
7609
7610
7611
7612
7613
7614
7615
7616
7617
7618
7619
7620
7621
7622
7623
7624
7625
7626
7627
7628
7629
7630
7631
7632
7633
7634
7635
7636
7637
7638
7639
7640
7641
7642
7643
7644
7645
7646
7647
7648
7649
7650
7651
7652
7653
7654
7655
7656
7657
7658
7659
7660
7661
7662
7663
7664
7665
7666
7667
7668
7669
7670
7671
7672
7673
7674
7675
7676
7677
7678
7679
7680
7681
7682
7683
7684
7685
7686
7687
7688
7689
7690
7691
7692
7693
7694
7695
7696
7697
7698
7699
7700
7701
7702
7703
7704
7705
7706
7707
7708
7709
7710
7711
7712
7713
7714
7715
7716
7717
7718
7719
7720
7721
7722
7723
7724
7725
7726
7727
7728
7729
7730
7731
7732
7733
7734
7735
7736
7737
7738
7739
7740
7741
7742
7743
7744
7745
7746
7747
7748
7749
7750
7751
7752
7753
7754
7755
7756
7757
7758
7759
7760
7761
7762
7763
7764
7765
7766
7767
7768
7769
7770
7771
7772
7773
7774
7775
7776
7777
7778
7779
7780
7781
7782
7783
7784
7785
7786
7787
7788
7789
7790
7791
7792
7793
7794
7795
7796
7797
7798
7799
7800
7801
7802
7803
7804
7805
7806
7807
7808
7809
7810
7811
7812
7813
7814
7815
7816
7817
7818
7819
7820
7821
7822
7823
7824
7825
7826
7827
7828
7829
7830
7831
7832
7833
7834
7835
7836
7837
7838
7839
7840
7841
7842
7843
7844
7845
7846
7847
7848
7849
7850
7851
7852
7853
7854
7855
7856
7857
7858
7859
7860
7861
7862
7863
7864
7865
7866
7867
7868
7869
7870
7871
7872
7873
7874
7875
7876
7877
7878
7879
7880
7881
7882
7883
7884
7885
7886
7887
7888
7889
7890
7891
7892
7893
7894
7895
7896
7897
7898
7899
7900
7901
7902
7903
7904
7905
7906
7907
7908
7909
7910
7911
7912
7913
7914
7915
7916
7917
7918
7919
7920
7921
7922
7923
7924
7925
7926
7927
7928
7929
7930
7931
7932
7933
7934
7935
7936
7937
7938
7939
7940
7941
7942
7943
7944
7945
7946
7947
7948
7949
7950
7951
7952
7953
7954
7955
7956
7957
7958
7959
7960
7961
7962
7963
7964
7965
7966
7967
7968
7969
7970
7971
7972
7973
7974
7975
7976
7977
7978
7979
7980
7981
7982
7983
7984
7985
7986
7987
7988
7989
7990
7991
7992
7993
7994
7995
7996
7997
7998
7999
8000
8001
8002
8003
8004
8005
8006
8007
8008
8009
8010
8011
8012
8013
8014
8015
8016
8017
8018
8019
8020
8021
8022
8023
8024
8025
8026
8027
8028
8029
8030
8031
8032
8033
8034
8035
8036
8037
8038
8039
8040
8041
8042
8043
8044
8045
8046
8047
8048
8049
8050
8051
8052
8053
8054
8055
8056
8057
8058
8059
8060
8061
8062
8063
8064
8065
8066
8067
8068
8069
8070
8071
8072
8073
8074
8075
8076
8077
8078
8079
8080
8081
8082
8083
8084
8085
8086
8087
8088
8089
8090
8091
8092
8093
8094
8095
8096
8097
8098
8099
8100
8101
8102
8103
8104
8105
8106
8107
8108
8109
8110
8111
8112
8113
8114
8115
8116
8117
8118
8119
8120
8121
8122
8123
8124
8125
8126
8127
8128
8129
8130
8131
8132
8133
8134
8135
8136
8137
8138
8139
8140
8141
8142
8143
8144
8145
8146
8147
8148
8149
8150
8151
8152
8153
8154
8155
8156
8157
8158
8159
8160
8161
8162
8163
8164
8165
8166
8167
8168
8169
8170
8171
8172
8173
8174
8175
8176
8177
8178
8179
8180
8181
8182
8183
8184
8185
8186
8187
8188
8189
8190
8191
8192
8193
8194
8195
8196
8197
8198
8199
8200
8201
8202
8203
8204
8205
8206
8207
8208
8209
8210
8211
8212
8213
8214
8215
8216
8217
8218
8219
8220
8221
8222
8223
8224
8225
8226
8227
8228
8229
8230
8231
8232
8233
8234
8235
8236
8237
8238
8239
8240
8241
8242
8243
8244
8245
8246
8247
8248
8249
8250
8251
8252
8253
8254
8255
8256
8257
8258
8259
8260
8261
8262
8263
8264
8265
8266
8267
8268
8269
8270
8271
8272
8273
8274
8275
8276
8277
8278
8279
8280
8281
8282
8283
8284
8285
8286
8287
8288
8289
8290
8291
8292
8293
8294
8295
8296
8297
8298
8299
8300
8301
8302
8303
8304
8305
8306
8307
8308
8309
8310
8311
8312
8313
8314
8315
8316
8317
8318
8319
8320
8321
8322
8323
8324
8325
8326
8327
8328
8329
8330
8331
8332
8333
8334
8335
8336
8337
8338
8339
8340
8341
8342
8343
8344
8345
8346
8347
8348
8349
8350
8351
8352
8353
8354
8355
8356
8357
8358
8359
8360
8361
8362
8363
8364
8365
8366
8367
8368
8369
8370
8371
8372
8373
8374
8375
8376
8377
8378
8379
8380
8381
8382
8383
8384
8385
8386
8387
8388
8389
8390
8391
8392
8393
8394
8395
8396
8397
8398
8399
8400
8401
8402
8403
8404
8405
8406
8407
8408
8409
8410
8411
8412
8413
8414
8415
8416
8417
8418
8419
8420
8421
8422
8423
8424
8425
8426
8427
8428
8429
8430
8431
8432
8433
8434
8435
8436
8437
8438
8439
8440
8441
8442
8443
8444
8445
8446
8447
8448
8449
8450
8451
8452
8453
8454
8455
8456
8457
8458
8459
8460
8461
8462
8463
8464
8465
8466
8467
8468
8469
8470
8471
8472
8473
8474
8475
8476
8477
8478
8479
8480
8481
8482
8483
8484
8485
8486
8487
8488
8489
8490
8491
8492
8493
8494
8495
8496
8497
8498
8499
8500
8501
8502
8503
8504
8505
8506
8507
8508
8509
8510
8511
8512
8513
8514
8515
8516
8517
8518
8519
8520
8521
8522
8523
8524
8525
8526
8527
8528
8529
8530
8531
8532
8533
8534
8535
8536
8537
8538
8539
8540
8541
8542
8543
8544
8545
8546
8547
8548
8549
8550
8551
8552
8553
8554
8555
8556
8557
8558
8559
8560
8561
8562
8563
8564
8565
8566
8567
8568
8569
8570
8571
8572
8573
8574
8575
8576
8577
8578
8579
8580
8581
8582
8583
8584
8585
8586
8587
8588
8589
8590
8591
8592
8593
8594
8595
8596
8597
8598
8599
8600
8601
8602
8603
8604
8605
8606
8607
8608
8609
8610
8611
8612
8613
8614
8615
8616
8617
8618
8619
8620
8621
8622
8623
8624
8625
8626
8627
8628
8629
8630
8631
8632
8633
8634
8635
8636
8637
8638
8639
8640
8641
8642
8643
8644
8645
8646
8647
8648
8649
8650
8651
8652
8653
8654
8655
8656
8657
8658
8659
8660
8661
8662
8663
8664
8665
8666
8667
8668
8669
8670
8671
8672
8673
8674
8675
8676
8677
8678
8679
8680
8681
8682
8683
8684
8685
8686
8687
8688
8689
8690
8691
8692
8693
8694
8695
8696
8697
8698
8699
8700
8701
8702
8703
8704
8705
8706
8707
8708
8709
8710
8711
8712
8713
8714
8715
8716
8717
8718
8719
8720
8721
8722
8723
8724
8725
8726
8727
8728
8729
8730
8731
8732
8733
8734
8735
8736
8737
8738
8739
8740
8741
8742
8743
8744
8745
8746
8747
8748
8749
8750
8751
8752
8753
8754
8755
8756
8757
8758
8759
8760
8761
8762
8763
8764
8765
8766
8767
8768
8769
8770
8771
8772
8773
8774
8775
8776
8777
8778
8779
8780
8781
8782
8783
8784
8785
8786
8787
8788
8789
8790
8791
8792
8793
8794
8795
8796
8797
8798
8799
8800
8801
8802
8803
8804
8805
8806
8807
8808
8809
8810
8811
8812
8813
8814
8815
8816
8817
8818
8819
8820
8821
8822
8823
8824
8825
8826
8827
8828
8829
8830
8831
8832
8833
8834
8835
8836
8837
8838
8839
8840
8841
8842
8843
8844
8845
8846
8847
8848
8849
8850
8851
8852
8853
8854
8855
8856
8857
8858
8859
8860
8861
8862
8863
8864
8865
8866
8867
8868
8869
8870
8871
8872
8873
8874
8875
8876
8877
8878
8879
8880
8881
8882
8883
8884
8885
8886
8887
8888
8889
8890
8891
8892
8893
8894
8895
8896
8897
8898
8899
8900
8901
8902
8903
8904
8905
8906
8907
8908
8909
8910
8911
8912
8913
8914
8915
8916
8917
8918
8919
8920
8921
8922
8923
8924
8925
8926
8927
8928
8929
8930
8931
8932
8933
8934
8935
8936
8937
8938
8939
8940
8941
8942
8943
8944
8945
8946
8947
8948
8949
8950
8951
8952
8953
8954
8955
8956
8957
8958
8959
8960
8961
8962
8963
8964
8965
8966
8967
8968
8969
8970
8971
8972
8973
8974
8975
8976
8977
8978
8979
8980
8981
8982
8983
8984
8985
8986
8987
8988
8989
8990
8991
8992
8993
8994
8995
8996
8997
8998
8999
9000
9001
9002
9003
9004
9005
9006
9007
9008
9009
9010
9011
9012
9013
9014
9015
9016
9017
9018
9019
9020
9021
9022
9023
9024
9025
9026
9027
9028
9029
9030
9031
9032
9033
9034
9035
9036
9037
9038
9039
9040
9041
9042
9043
9044
9045
9046
9047
9048
9049
9050
9051
9052
9053
9054
9055
9056
9057
9058
9059
9060
9061
9062
9063
9064
9065
9066
9067
9068
9069
9070
9071
9072
9073
9074
9075
9076
9077
9078
9079
9080
9081
9082
9083
9084
9085
9086
9087
9088
9089
9090
9091
9092
9093
9094
9095
9096
9097
9098
9099
9100
9101
9102
9103
9104
9105
9106
9107
9108
9109
9110
9111
9112
9113
9114
9115
9116
9117
9118
9119
9120
9121
9122
9123
9124
9125
9126
9127
9128
9129
9130
9131
9132
9133
9134
9135
9136
9137
9138
9139
9140
9141
9142
9143
9144
9145
9146
9147
9148
9149
9150
9151
9152
9153
9154
9155
9156
9157
9158
9159
9160
9161
9162
9163
9164
9165
9166
9167
9168
9169
9170
9171
9172
9173
9174
9175
9176
9177
9178
9179
9180
9181
9182
9183
9184
9185
9186
9187
9188
9189
9190
9191
9192
9193
9194
9195
9196
9197
9198
9199
9200
9201
9202
9203
9204
9205
9206
9207
9208
9209
9210
9211
9212
9213
9214
9215
9216
9217
9218
9219
9220
9221
9222
9223
9224
9225
9226
9227
9228
9229
9230
9231
9232
9233
9234
9235
9236
9237
9238
9239
9240
9241
9242
9243
9244
9245
9246
9247
9248
9249
9250
9251
9252
9253
9254
9255
9256
9257
9258
9259
9260
9261
9262
9263
9264
9265
9266
9267
9268
9269
9270
9271
9272
9273
9274
9275
9276
9277
9278
9279
9280
9281
9282
9283
9284
9285
9286
9287
9288
9289
9290
9291
9292
9293
9294
9295
9296
9297
9298
9299
9300
9301
9302
9303
9304
9305
9306
9307
9308
9309
9310
9311
9312
9313
9314
9315
9316
9317
9318
9319
9320
9321
9322
9323
9324
9325
9326
9327
9328
9329
9330
9331
9332
9333
9334
9335
9336
9337
9338
9339
9340
9341
9342
9343
9344
9345
9346
9347
9348
9349
9350
9351
9352
9353
9354
9355
9356
9357
9358
9359
9360
9361
9362
9363
9364
9365
9366
9367
9368
9369
9370
9371
9372
9373
9374
9375
9376
9377
9378
9379
9380
9381
9382
9383
9384
9385
9386
9387
9388
9389
9390
9391
9392
9393
9394
9395
9396
9397
9398
9399
9400
9401
9402
9403
9404
9405
9406
9407
9408
9409
9410
9411
9412
9413
9414
9415
9416
9417
9418
9419
9420
9421
9422
9423
9424
9425
9426
9427
9428
9429
9430
9431
9432
9433
9434
9435
9436
9437
9438
9439
9440
9441
9442
9443
9444
9445
9446
9447
9448
9449
9450
9451
9452
9453
9454
9455
9456
9457
9458
9459
9460
9461
9462
9463
9464
9465
9466
9467
9468
9469
9470
9471
9472
9473
9474
9475
9476
9477
9478
9479
9480
9481
9482
9483
9484
9485
9486
9487
9488
9489
9490
9491
9492
9493
9494
9495
9496
9497
9498
9499
9500
9501
9502
9503
9504
9505
9506
9507
9508
9509
9510
9511
9512
9513
9514
9515
9516
9517
9518
9519
9520
9521
9522
9523
9524
9525
9526
9527
9528
9529
9530
9531
9532
9533
9534
9535
9536
9537
9538
9539
9540
9541
9542
9543
9544
9545
9546
9547
9548
9549
9550
9551
9552
9553
9554
9555
9556
9557
9558
9559
9560
9561
9562
9563
9564
9565
9566
9567
9568
9569
9570
9571
9572
9573
9574
9575
9576
9577
9578
9579
9580
9581
9582
9583
9584
9585
9586
9587
9588
9589
9590
9591
9592
9593
9594
9595
9596
9597
9598
9599
9600
9601
9602
9603
9604
9605
9606
9607
9608
9609
9610
9611
9612
9613
9614
9615
9616
9617
9618
9619
9620
9621
9622
9623
9624
9625
9626
9627
9628
9629
9630
9631
9632
9633
9634
9635
9636
9637
9638
9639
9640
9641
9642
9643
9644
9645
9646
9647
9648
9649
9650
9651
9652
9653
9654
9655
9656
9657
9658
9659
9660
9661
9662
9663
9664
9665
9666
9667
9668
9669
9670
9671
9672
9673
9674
9675
9676
9677
9678
9679
9680
9681
9682
9683
9684
9685
9686
9687
9688
9689
9690
9691
9692
9693
9694
9695
9696
9697
9698
9699
9700
9701
9702
9703
9704
9705
9706
9707
9708
9709
9710
9711
9712
9713
9714
9715
9716
9717
9718
9719
9720
9721
9722
9723
9724
9725
9726
9727
9728
9729
9730
9731
9732
9733
9734
9735
9736
9737
9738
9739
9740
9741
9742
9743
9744
9745
9746
9747
9748
9749
9750
9751
9752
9753
9754
9755
9756
9757
9758
9759
9760
9761
9762
9763
9764
9765
9766
9767
9768
9769
9770
9771
9772
9773
9774
9775
9776
9777
9778
9779
9780
9781
9782
9783
9784
9785
9786
9787
9788
9789
9790
9791
9792
9793
9794
9795
9796
9797
9798
9799
9800
9801
9802
9803
9804
9805
9806
9807
9808
9809
9810
9811
9812
9813
9814
9815
9816
9817
9818
9819
9820
9821
9822
9823
9824
9825
9826
9827
9828
9829
9830
9831
9832
9833
9834
9835
9836
9837
9838
9839
9840
9841
9842
9843
9844
9845
9846
9847
9848
9849
9850
9851
9852
9853
9854
9855
9856
9857
9858
9859
9860
9861
9862
9863
9864
9865
9866
9867
9868
9869
9870
9871
9872
9873
9874
9875
9876
9877
9878
9879
9880
9881
9882
9883
9884
9885
9886
9887
9888
9889
9890
9891
9892
9893
9894
9895
9896
9897
9898
9899
9900
9901
9902
9903
9904
9905
9906
9907
9908
9909
9910
9911
9912
9913
9914
9915
9916
9917
9918
9919
9920
9921
9922
9923
9924
9925
9926
9927
9928
9929
9930
9931
9932
9933
9934
9935
9936
9937
9938
9939
9940
9941
9942
9943
9944
9945
9946
9947
9948
9949
9950
9951
9952
9953
9954
9955
9956
9957
9958
9959
9960
9961
9962
9963
9964
9965
9966
9967
9968
9969
9970
9971
9972
9973
9974
9975
9976
9977
9978
9979
9980
9981
9982
9983
9984
9985
9986
9987
9988
9989
9990
9991
9992
9993
9994
9995
9996
9997
9998
9999
10000
10001
10002
10003
10004
10005
10006
10007
10008
10009
10010
10011
10012
10013
10014
10015
10016
10017
10018
10019
10020
10021
10022
10023
10024
10025
10026
10027
10028
10029
10030
10031
10032
10033
10034
10035
10036
10037
10038
10039
10040
10041
10042
10043
10044
10045
10046
10047
10048
10049
10050
10051
10052
10053
10054
10055
10056
10057
10058
10059
10060
10061
10062
10063
10064
10065
10066
10067
10068
10069
10070
10071
10072
10073
10074
10075
10076
10077
10078
10079
10080
10081
10082
10083
10084
10085
10086
10087
10088
10089
10090
10091
10092
10093
10094
10095
10096
10097
10098
10099
10100
10101
10102
10103
10104
10105
10106
10107
10108
10109
10110
10111
10112
10113
10114
10115
10116
10117
10118
10119
10120
10121
10122
10123
10124
10125
10126
10127
10128
10129
10130
10131
10132
10133
10134
10135
10136
10137
10138
10139
10140
10141
10142
10143
10144
10145
10146
10147
10148
10149
10150
10151
10152
10153
10154
10155
10156
10157
10158
10159
10160
10161
10162
10163
10164
10165
10166
10167
10168
10169
10170
10171
10172
10173
10174
10175
10176
10177
10178
10179
10180
10181
10182
10183
10184
10185
10186
10187
10188
10189
10190
10191
10192
10193
10194
10195
10196
10197
10198
10199
10200
10201
10202
10203
10204
10205
10206
10207
10208
10209
10210
10211
10212
10213
10214
10215
10216
10217
10218
10219
10220
10221
10222
10223
10224
10225
10226
10227
10228
10229
10230
10231
10232
10233
10234
10235
10236
10237
10238
10239
10240
10241
10242
10243
10244
10245
10246
10247
10248
10249
10250
10251
10252
10253
10254
10255
10256
10257
10258
10259
10260
10261
10262
10263
10264
10265
10266
10267
10268
10269
10270
10271
10272
10273
10274
10275
10276
10277
10278
10279
10280
10281
10282
10283
10284
10285
10286
10287
10288
10289
10290
10291
10292
10293
10294
10295
10296
10297
10298
10299
10300
10301
10302
10303
10304
10305
10306
10307
10308
10309
10310
10311
10312
10313
10314
10315
10316
10317
10318
10319
10320
10321
10322
10323
10324
10325
10326
10327
10328
10329
10330
10331
10332
10333
10334
10335
10336
10337
10338
10339
10340
10341
10342
10343
10344
10345
10346
10347
10348
10349
10350
10351
10352
10353
10354
10355
10356
10357
10358
10359
10360
10361
10362
10363
10364
10365
10366
10367
10368
10369
10370
10371
10372
10373
10374
10375
10376
10377
10378
10379
10380
10381
10382
10383
10384
10385
10386
10387
10388
10389
10390
10391
10392
10393
10394
10395
10396
10397
10398
10399
10400
10401
10402
10403
10404
10405
10406
10407
10408
10409
10410
10411
10412
10413
10414
10415
10416
10417
10418
10419
10420
10421
10422
10423
10424
10425
10426
10427
10428
10429
10430
10431
10432
10433
10434
10435
10436
10437
10438
10439
10440
10441
10442
10443
10444
10445
10446
10447
10448
10449
10450
10451
10452
10453
10454
10455
10456
10457
10458
10459
10460
10461
10462
10463
10464
10465
10466
10467
10468
10469
10470
10471
10472
10473
10474
10475
10476
10477
10478
10479
10480
10481
10482
10483
10484
10485
10486
10487
10488
10489
10490
10491
10492
10493
10494
10495
10496
10497
10498
10499
10500
10501
10502
10503
10504
10505
10506
10507
10508
10509
10510
10511
10512
10513
10514
10515
10516
10517
10518
10519
10520
10521
10522
10523
10524
10525
10526
10527
10528
10529
10530
10531
10532
10533
10534
10535
10536
10537
10538
10539
10540
10541
10542
10543
10544
10545
10546
10547
10548
10549
10550
10551
10552
10553
10554
10555
10556
10557
10558
10559
10560
10561
10562
10563
10564
10565
10566
10567
10568
10569
10570
10571
10572
10573
10574
10575
10576
10577
10578
10579
10580
10581
10582
10583
10584
10585
10586
10587
10588
10589
10590
10591
10592
10593
10594
10595
10596
10597
10598
10599
10600
10601
10602
10603
10604
10605
10606
10607
10608
10609
10610
10611
10612
10613
10614
10615
10616
10617
10618
10619
10620
10621
10622
10623
10624
10625
10626
10627
10628
10629
10630
10631
10632
10633
10634
10635
10636
10637
10638
10639
10640
10641
10642
10643
10644
10645
10646
10647
10648
10649
10650
10651
10652
10653
10654
10655
10656
10657
10658
10659
10660
10661
10662
10663
10664
10665
10666
10667
10668
10669
10670
10671
10672
10673
10674
10675
10676
10677
10678
10679
10680
10681
10682
10683
10684
10685
10686
10687
10688
10689
10690
10691
10692
10693
10694
10695
10696
10697
10698
10699
10700
10701
10702
10703
10704
10705
10706
10707
10708
10709
10710
10711
10712
10713
10714
10715
10716
10717
10718
10719
10720
10721
10722
10723
10724
10725
10726
10727
10728
10729
10730
10731
10732
10733
10734
10735
10736
10737
10738
10739
10740
10741
10742
10743
10744
10745
10746
10747
10748
10749
10750
10751
10752
10753
10754
10755
10756
10757
10758
10759
10760
10761
10762
10763
10764
10765
10766
10767
10768
10769
10770
10771
10772
10773
10774
10775
10776
10777
10778
10779
10780
10781
10782
10783
10784
10785
10786
10787
10788
10789
10790
10791
10792
10793
10794
10795
10796
10797
10798
10799
10800
10801
10802
10803
10804
10805
10806
10807
10808
10809
10810
10811
10812
10813
10814
10815
10816
10817
10818
10819
10820
10821
10822
10823
10824
10825
10826
10827
10828
10829
10830
10831
10832
10833
10834
10835
10836
10837
10838
10839
10840
10841
10842
10843
10844
10845
10846
10847
10848
10849
10850
10851
10852
10853
10854
10855
10856
10857
10858
10859
10860
10861
10862
10863
10864
10865
10866
10867
10868
10869
10870
10871
10872
10873
10874
10875
10876
10877
10878
10879
10880
10881
10882
10883
10884
10885
10886
10887
10888
10889
10890
10891
10892
10893
10894
10895
10896
10897
10898
10899
10900
10901
10902
10903
10904
10905
10906
10907
10908
10909
10910
10911
10912
10913
10914
10915
10916
10917
10918
10919
10920
10921
10922
10923
10924
10925
10926
10927
10928
10929
10930
10931
10932
10933
10934
10935
10936
10937
10938
10939
10940
10941
10942
10943
10944
10945
10946
10947
10948
10949
10950
10951
10952
10953
10954
10955
10956
10957
10958
10959
10960
10961
10962
10963
10964
10965
10966
10967
10968
10969
10970
10971
10972
10973
10974
10975
10976
10977
10978
10979
10980
10981
10982
10983
10984
10985
10986
10987
10988
10989
10990
10991
10992
10993
10994
10995
10996
10997
10998
10999
11000
11001
11002
11003
11004
11005
11006
11007
11008
11009
11010
11011
11012
11013
11014
11015
11016
11017
11018
11019
11020
11021
11022
11023
11024
11025
11026
11027
11028
11029
11030
11031
11032
11033
11034
11035
11036
11037
11038
11039
11040
11041
11042
11043
11044
11045
11046
11047
11048
11049
11050
11051
11052
11053
11054
11055
11056
11057
11058
11059
11060
11061
11062
11063
11064
11065
11066
11067
11068
11069
11070
11071
11072
11073
11074
11075
11076
11077
11078
11079
11080
11081
11082
11083
11084
11085
11086
11087
11088
11089
11090
11091
11092
11093
11094
11095
11096
11097
11098
11099
11100
11101
11102
11103
11104
11105
11106
11107
11108
11109
11110
11111
11112
11113
11114
11115
11116
11117
11118
11119
11120
11121
11122
11123
11124
11125
11126
11127
11128
11129
11130
11131
11132
11133
11134
11135
11136
11137
11138
11139
11140
11141
11142
11143
11144
11145
11146
11147
11148
11149
11150
11151
11152
11153
11154
11155
11156
11157
11158
11159
11160
11161
11162
11163
11164
11165
11166
11167
11168
11169
11170
11171
11172
11173
11174
11175
11176
11177
11178
11179
11180
11181
11182
11183
11184
11185
11186
11187
11188
11189
11190
11191
11192
11193
11194
11195
11196
11197
11198
11199
11200
11201
11202
11203
11204
11205
11206
11207
11208
11209
11210
11211
11212
11213
11214
11215
11216
11217
11218
11219
11220
11221
11222
11223
11224
11225
11226
11227
11228
11229
11230
11231
11232
11233
11234
11235
11236
11237
11238
11239
11240
11241
11242
11243
11244
11245
11246
11247
11248
11249
11250
11251
11252
11253
11254
11255
11256
11257
11258
11259
11260
11261
11262
11263
11264
11265
11266
11267
11268
11269
11270
11271
11272
11273
11274
11275
11276
11277
11278
11279
11280
11281
11282
11283
11284
11285
11286
11287
11288
11289
11290
11291
11292
11293
11294
11295
11296
11297
11298
11299
11300
11301
11302
11303
11304
11305
11306
11307
11308
11309
11310
11311
11312
11313
11314
11315
11316
11317
11318
11319
11320
11321
11322
11323
11324
11325
11326
11327
11328
11329
11330
11331
11332
11333
11334
11335
11336
11337
11338
11339
11340
11341
11342
11343
11344
11345
11346
11347
11348
11349
11350
11351
11352
11353
11354
11355
11356
11357
11358
11359
11360
11361
11362
11363
11364
11365
11366
11367
11368
11369
11370
11371
11372
11373
11374
11375
11376
11377
11378
11379
11380
11381
11382
11383
11384
11385
11386
11387
11388
11389
11390
11391
11392
11393
11394
11395
11396
11397
11398
11399
11400
11401
11402
11403
11404
11405
11406
11407
11408
11409
11410
11411
11412
11413
11414
11415
11416
11417
11418
11419
11420
11421
11422
11423
11424
11425
11426
11427
11428
11429
11430
11431
11432
11433
11434
11435
11436
11437
11438
11439
11440
11441
11442
11443
11444
11445
11446
11447
11448
11449
11450
11451
11452
11453
11454
11455
11456
11457
11458
11459
11460
11461
11462
11463
11464
11465
11466
11467
11468
11469
11470
11471
11472
11473
11474
11475
11476
11477
11478
11479
11480
11481
11482
11483
11484
11485
11486
11487
11488
11489
11490
11491
11492
11493
11494
11495
11496
11497
11498
11499
11500
11501
11502
11503
11504
11505
11506
11507
11508
11509
11510
11511
11512
11513
11514
11515
11516
11517
11518
11519
11520
11521
11522
11523
11524
11525
11526
11527
11528
11529
11530
11531
11532
11533
11534
11535
11536
11537
11538
11539
11540
11541
11542
11543
11544
11545
11546
11547
11548
11549
11550
11551
11552
11553
11554
11555
11556
11557
11558
11559
11560
11561
11562
11563
11564
11565
11566
11567
11568
11569
11570
11571
11572
11573
11574
11575
11576
11577
11578
11579
11580
11581
11582
11583
11584
11585
11586
11587
11588
11589
11590
11591
11592
11593
11594
11595
11596
11597
11598
11599
11600
11601
11602
11603
11604
11605
11606
11607
11608
11609
11610
11611
11612
11613
11614
11615
11616
11617
11618
11619
11620
11621
11622
11623
11624
11625
11626
11627
11628
11629
11630
11631
11632
11633
11634
11635
11636
11637
11638
11639
11640
11641
11642
11643
11644
11645
11646
11647
11648
11649
11650
11651
11652
11653
11654
11655
11656
11657
11658
11659
11660
11661
11662
11663
11664
11665
11666
11667
11668
11669
11670
11671
11672
11673
11674
11675
11676
11677
11678
11679
11680
11681
11682
11683
11684
11685
11686
11687
11688
11689
11690
11691
11692
11693
11694
11695
11696
11697
11698
11699
11700
11701
11702
11703
11704
11705
11706
11707
11708
11709
11710
11711
11712
11713
11714
11715
11716
11717
11718
11719
11720
11721
11722
11723
11724
11725
11726
11727
11728
11729
11730
11731
11732
11733
11734
11735
11736
11737
11738
11739
11740
11741
11742
11743
11744
11745
11746
11747
11748
11749
11750
11751
11752
11753
11754
11755
11756
11757
11758
11759
11760
11761
11762
11763
11764
11765
11766
11767
11768
11769
11770
11771
11772
11773
11774
11775
11776
11777
11778
11779
11780
11781
11782
11783
11784
11785
11786
11787
11788
11789
11790
11791
11792
11793
11794
11795
11796
11797
11798
11799
11800
11801
11802
11803
11804
11805
11806
11807
11808
11809
11810
11811
11812
11813
11814
11815
11816
11817
11818
11819
11820
11821
11822
11823
11824
11825
11826
11827
11828
11829
11830
11831
11832
11833
11834
11835
11836
11837
11838
11839
11840
11841
11842
11843
11844
11845
11846
11847
11848
11849
11850
11851
11852
11853
11854
11855
11856
11857
11858
11859
11860
11861
11862
11863
11864
11865
11866
11867
11868
11869
11870
11871
11872
11873
11874
11875
11876
11877
11878
11879
11880
11881
11882
11883
11884
11885
11886
11887
11888
11889
11890
11891
11892
11893
11894
11895
11896
11897
11898
11899
11900
11901
11902
11903
11904
11905
11906
11907
11908
11909
11910
11911
11912
11913
11914
11915
11916
11917
11918
11919
11920
11921
11922
11923
11924
11925
11926
11927
11928
11929
11930
11931
11932
11933
11934
11935
11936
11937
11938
11939
11940
11941
11942
11943
11944
11945
11946
11947
11948
11949
11950
11951
11952
11953
11954
11955
11956
11957
11958
11959
11960
11961
11962
11963
11964
11965
11966
11967
11968
11969
11970
11971
11972
11973
11974
11975
11976
11977
11978
11979
11980
11981
11982
11983
11984
11985
11986
11987
11988
11989
11990
11991
11992
11993
11994
11995
11996
11997
11998
11999
12000
12001
12002
12003
12004
12005
12006
12007
12008
12009
12010
12011
12012
12013
12014
12015
12016
12017
12018
12019
12020
12021
12022
12023
12024
12025
12026
12027
12028
12029
12030
12031
12032
12033
12034
12035
12036
12037
12038
12039
12040
12041
12042
12043
12044
12045
12046
12047
12048
12049
12050
12051
12052
12053
12054
12055
12056
12057
12058
12059
12060
12061
12062
12063
12064
12065
12066
12067
12068
12069
12070
12071
12072
12073
12074
12075
12076
12077
12078
12079
12080
12081
12082
12083
12084
12085
12086
12087
12088
12089
12090
12091
12092
12093
12094
12095
12096
12097
12098
12099
12100
12101
12102
12103
12104
12105
12106
12107
12108
12109
12110
12111
12112
12113
12114
12115
12116
12117
12118
12119
12120
12121
12122
12123
12124
12125
12126
12127
12128
12129
12130
12131
12132
12133
12134
12135
12136
12137
12138
12139
12140
12141
12142
12143
12144
12145
12146
12147
12148
12149
12150
12151
12152
12153
12154
12155
12156
12157
12158
12159
12160
12161
12162
12163
12164
12165
12166
12167
12168
12169
12170
12171
12172
12173
12174
12175
12176
12177
12178
12179
12180
12181
12182
12183
12184
12185
12186
12187
12188
12189
12190
12191
12192
12193
12194
12195
12196
12197
12198
12199
12200
12201
12202
12203
12204
12205
12206
12207
12208
12209
12210
12211
12212
12213
12214
12215
12216
12217
12218
12219
12220
12221
12222
12223
12224
12225
12226
12227
12228
12229
12230
12231
12232
12233
12234
12235
12236
12237
12238
12239
12240
12241
12242
12243
12244
12245
12246
12247
12248
12249
12250
12251
12252
12253
12254
12255
12256
12257
12258
12259
12260
12261
12262
12263
12264
12265
12266
12267
12268
12269
12270
12271
12272
12273
12274
12275
12276
12277
12278
12279
12280
12281
12282
12283
12284
12285
12286
12287
12288
12289
12290
12291
12292
12293
12294
12295
12296
12297
12298
12299
12300
12301
12302
12303
12304
12305
12306
12307
12308
12309
12310
12311
12312
12313
12314
12315
12316
12317
12318
12319
12320
12321
12322
12323
12324
12325
12326
12327
12328
12329
12330
12331
12332
12333
12334
12335
12336
12337
12338
12339
12340
12341
12342
12343
12344
12345
12346
12347
12348
12349
12350
12351
12352
12353
12354
12355
12356
12357
12358
12359
12360
12361
12362
12363
12364
12365
12366
12367
12368
12369
12370
12371
12372
12373
12374
12375
12376
12377
12378
12379
12380
12381
12382
12383
12384
12385
12386
12387
12388
12389
12390
12391
12392
12393
12394
12395
12396
12397
12398
12399
12400
12401
12402
12403
12404
12405
12406
12407
12408
12409
12410
12411
12412
12413
12414
12415
12416
12417
12418
12419
12420
12421
12422
12423
12424
12425
12426
12427
12428
12429
12430
12431
12432
12433
12434
12435
12436
12437
12438
12439
12440
12441
12442
12443
12444
12445
12446
12447
12448
12449
12450
12451
12452
12453
12454
12455
12456
12457
12458
12459
12460
12461
12462
12463
12464
12465
12466
12467
12468
12469
12470
12471
12472
12473
12474
12475
12476
12477
12478
12479
12480
12481
12482
12483
12484
12485
12486
12487
12488
12489
12490
12491
12492
12493
12494
12495
12496
12497
12498
12499
12500
12501
12502
12503
12504
12505
12506
12507
12508
12509
12510
12511
12512
12513
12514
12515
12516
12517
12518
12519
12520
12521
12522
12523
12524
12525
12526
12527
12528
12529
12530
12531
12532
12533
12534
12535
12536
12537
12538
12539
12540
12541
12542
12543
12544
12545
12546
12547
12548
12549
12550
12551
12552
12553
12554
12555
12556
12557
12558
12559
12560
12561
12562
12563
12564
12565
12566
12567
12568
12569
12570
12571
12572
12573
12574
12575
12576
12577
12578
12579
12580
12581
12582
12583
12584
12585
12586
12587
12588
12589
12590
12591
12592
12593
12594
12595
12596
12597
12598
12599
12600
12601
12602
12603
12604
12605
12606
12607
12608
12609
12610
12611
12612
12613
12614
12615
12616
12617
12618
12619
12620
12621
12622
12623
12624
12625
12626
12627
12628
12629
12630
12631
12632
12633
12634
12635
12636
12637
12638
12639
12640
12641
12642
12643
12644
12645
12646
12647
12648
12649
12650
12651
12652
12653
12654
12655
12656
12657
12658
12659
12660
12661
12662
12663
12664
12665
12666
12667
12668
12669
12670
12671
12672
12673
12674
12675
12676
12677
12678
12679
12680
12681
12682
12683
12684
12685
12686
12687
12688
12689
12690
12691
12692
12693
12694
12695
12696
12697
12698
12699
12700
12701
12702
12703
12704
12705
12706
12707
12708
12709
12710
12711
12712
12713
12714
12715
12716
12717
12718
12719
12720
12721
12722
12723
12724
12725
12726
12727
12728
12729
12730
12731
12732
12733
12734
12735
12736
12737
12738
12739
12740
12741
12742
12743
12744
12745
12746
12747
12748
12749
12750
12751
12752
12753
12754
12755
12756
12757
12758
12759
12760
12761
12762
12763
12764
12765
12766
12767
12768
12769
12770
12771
12772
12773
12774
12775
12776
12777
12778
12779
12780
12781
12782
12783
12784
12785
12786
12787
12788
12789
12790
12791
12792
12793
12794
12795
12796
12797
12798
12799
12800
12801
12802
12803
12804
12805
12806
12807
12808
12809
12810
12811
12812
12813
12814
12815
12816
12817
12818
12819
12820
12821
12822
12823
12824
12825
12826
12827
12828
12829
12830
12831
12832
12833
12834
12835
12836
12837
12838
12839
12840
12841
12842
12843
12844
12845
12846
12847
12848
12849
12850
12851
12852
12853
12854
12855
12856
12857
12858
12859
12860
12861
12862
12863
12864
12865
12866
12867
12868
12869
12870
12871
12872
12873
12874
12875
12876
12877
12878
12879
12880
12881
12882
12883
12884
12885
12886
12887
12888
12889
12890
12891
12892
12893
12894
12895
12896
12897
12898
12899
12900
12901
12902
12903
12904
12905
12906
12907
12908
12909
12910
12911
12912
12913
12914
12915
12916
12917
12918
12919
12920
12921
12922
12923
12924
12925
12926
12927
12928
12929
12930
12931
12932
12933
12934
12935
12936
12937
12938
12939
12940
12941
12942
12943
12944
12945
12946
12947
12948
12949
12950
12951
12952
12953
12954
12955
12956
12957
12958
12959
12960
12961
12962
12963
12964
12965
12966
12967
12968
12969
12970
12971
12972
12973
12974
12975
12976
12977
12978
12979
12980
12981
12982
12983
12984
12985
12986
12987
12988
12989
12990
12991
12992
12993
12994
12995
12996
12997
12998
12999
13000
13001
13002
13003
13004
13005
13006
13007
13008
13009
13010
13011
13012
13013
13014
13015
13016
13017
13018
13019
13020
13021
13022
13023
13024
13025
13026
13027
13028
13029
13030
13031
13032
13033
13034
13035
13036
13037
13038
13039
13040
13041
13042
13043
13044
13045
13046
13047
13048
13049
13050
13051
13052
13053
13054
13055
13056
13057
13058
13059
13060
13061
13062
13063
13064
13065
13066
13067
13068
13069
13070
13071
13072
13073
13074
13075
13076
13077
13078
13079
13080
13081
13082
13083
13084
13085
13086
13087
13088
13089
13090
13091
13092
13093
13094
13095
13096
13097
13098
13099
13100
13101
13102
13103
13104
13105
13106
13107
13108
13109
13110
13111
13112
13113
13114
13115
13116
13117
13118
13119
13120
13121
13122
13123
13124
13125
13126
13127
13128
13129
13130
13131
13132
13133
13134
13135
13136
13137
13138
13139
13140
13141
13142
13143
13144
13145
13146
13147
13148
13149
13150
13151
13152
13153
13154
13155
13156
13157
13158
13159
13160
13161
13162
13163
13164
13165
13166
13167
13168
13169
13170
13171
13172
13173
13174
13175
13176
13177
13178
13179
13180
13181
13182
13183
13184
13185
13186
13187
13188
13189
13190
13191
13192
13193
13194
13195
13196
13197
13198
13199
13200
13201
13202
13203
13204
13205
13206
13207
13208
13209
13210
13211
13212
13213
13214
13215
13216
13217
13218
13219
13220
13221
13222
13223
13224
13225
13226
13227
13228
13229
13230
13231
13232
13233
13234
13235
13236
13237
13238
13239
13240
13241
13242
13243
13244
13245
13246
13247
13248
13249
13250
13251
13252
13253
13254
13255
13256
13257
13258
13259
13260
13261
13262
13263
13264
13265
13266
13267
13268
13269
13270
13271
13272
13273
13274
13275
13276
13277
13278
13279
13280
13281
13282
13283
13284
13285
13286
13287
13288
13289
13290
13291
13292
13293
13294
13295
13296
13297
13298
13299
13300
13301
13302
13303
13304
13305
13306
13307
13308
13309
13310
13311
13312
13313
13314
13315
13316
13317
13318
13319
13320
13321
13322
13323
13324
13325
13326
13327
13328
13329
13330
13331
13332
13333
13334
13335
13336
13337
13338
13339
13340
13341
13342
13343
13344
13345
13346
13347
13348
13349
13350
13351
13352
13353
13354
13355
13356
13357
13358
13359
13360
13361
13362
13363
13364
13365
13366
13367
13368
13369
13370
13371
13372
13373
13374
13375
13376
13377
13378
13379
13380
13381
13382
13383
13384
13385
13386
13387
13388
13389
13390
13391
13392
13393
13394
13395
13396
13397
13398
13399
13400
13401
13402
13403
13404
13405
13406
13407
13408
13409
13410
13411
13412
13413
13414
13415
13416
13417
13418
13419
13420
13421
13422
13423
13424
13425
13426
13427
13428
13429
13430
13431
13432
13433
13434
13435
13436
13437
13438
13439
13440
13441
13442
13443
13444
13445
13446
13447
13448
13449
13450
13451
13452
13453
13454
13455
13456
13457
13458
13459
13460
13461
13462
13463
13464
13465
13466
13467
13468
13469
13470
13471
13472
13473
13474
13475
13476
13477
13478
13479
13480
13481
13482
13483
13484
13485
13486
13487
13488
13489
13490
13491
13492
13493
13494
13495
13496
13497
13498
13499
13500
13501
13502
13503
13504
13505
13506
13507
13508
13509
13510
13511
13512
13513
13514
13515
13516
13517
13518
13519
13520
13521
13522
13523
13524
13525
13526
13527
13528
13529
13530
13531
13532
13533
13534
13535
13536
13537
13538
13539
13540
13541
13542
13543
13544
13545
13546
13547
13548
13549
13550
13551
13552
13553
13554
13555
13556
13557
13558
13559
13560
13561
13562
13563
13564
13565
13566
13567
13568
13569
13570
13571
13572
13573
13574
13575
13576
13577
13578
13579
13580
13581
13582
13583
13584
13585
13586
13587
13588
13589
13590
13591
13592
13593
13594
13595
13596
13597
13598
13599
13600
13601
13602
13603
13604
13605
13606
13607
13608
13609
13610
13611
13612
13613
13614
13615
13616
13617
13618
13619
13620
13621
13622
13623
13624
13625
13626
13627
13628
13629
13630
13631
13632
13633
13634
13635
13636
13637
13638
13639
13640
13641
13642
13643
13644
13645
13646
13647
13648
13649
13650
13651
13652
13653
13654
13655
13656
13657
13658
13659
13660
13661
13662
13663
13664
13665
13666
13667
13668
13669
13670
13671
13672
13673
13674
13675
13676
13677
13678
13679
13680
13681
13682
13683
13684
13685
13686
13687
13688
13689
13690
13691
13692
13693
13694
13695
13696
13697
13698
13699
13700
13701
13702
13703
13704
13705
13706
13707
13708
13709
13710
13711
13712
13713
13714
13715
13716
13717
13718
13719
13720
13721
13722
13723
13724
13725
13726
13727
13728
13729
13730
13731
13732
13733
13734
13735
13736
13737
13738
13739
13740
13741
13742
13743
13744
13745
13746
13747
13748
13749
13750
13751
13752
13753
13754
13755
13756
13757
13758
13759
13760
13761
13762
13763
13764
13765
13766
13767
13768
13769
13770
13771
13772
13773
13774
13775
13776
13777
13778
13779
13780
13781
13782
13783
13784
13785
13786
13787
13788
13789
13790
13791
13792
13793
13794
13795
13796
13797
13798
13799
13800
13801
13802
13803
13804
13805
13806
13807
13808
13809
13810
13811
13812
13813
13814
13815
13816
13817
13818
13819
13820
13821
13822
13823
13824
13825
13826
13827
13828
13829
13830
13831
13832
13833
13834
13835
13836
13837
13838
13839
13840
13841
13842
13843
13844
13845
13846
13847
13848
13849
13850
13851
13852
13853
13854
13855
13856
13857
13858
13859
13860
13861
13862
13863
13864
13865
13866
13867
13868
13869
13870
13871
13872
13873
13874
13875
13876
13877
13878
13879
13880
13881
13882
13883
13884
13885
13886
13887
13888
13889
13890
13891
13892
13893
13894
13895
13896
13897
13898
13899
13900
13901
13902
13903
13904
13905
13906
13907
13908
13909
13910
13911
13912
13913
13914
13915
13916
13917
13918
13919
13920
13921
13922
13923
13924
13925
13926
13927
13928
13929
13930
13931
13932
13933
13934
13935
13936
13937
13938
13939
13940
13941
13942
13943
13944
13945
13946
13947
13948
13949
13950
13951
13952
13953
13954
13955
13956
13957
13958
13959
13960
13961
13962
13963
13964
13965
13966
13967
13968
13969
13970
13971
13972
13973
13974
13975
13976
13977
13978
13979
13980
13981
13982
13983
13984
13985
13986
13987
13988
13989
13990
13991
13992
13993
13994
13995
13996
13997
13998
13999
14000
14001
14002
14003
14004
14005
14006
14007
14008
14009
14010
14011
14012
14013
14014
14015
14016
14017
14018
14019
14020
14021
14022
14023
14024
14025
14026
14027
14028
14029
14030
14031
14032
14033
14034
14035
14036
14037
14038
14039
14040
14041
14042
14043
14044
14045
14046
14047
14048
14049
14050
14051
14052
14053
14054
14055
14056
14057
14058
14059
14060
14061
14062
14063
14064
14065
14066
14067
14068
14069
14070
14071
14072
14073
14074
14075
14076
14077
14078
14079
14080
14081
14082
14083
14084
14085
14086
14087
14088
14089
14090
14091
14092
14093
14094
14095
14096
14097
14098
14099
14100
14101
14102
14103
14104
14105
14106
14107
14108
14109
14110
14111
14112
14113
14114
14115
14116
14117
14118
14119
14120
14121
14122
14123
14124
14125
14126
14127
14128
14129
14130
14131
14132
14133
14134
14135
14136
14137
14138
14139
14140
14141
14142
14143
14144
14145
14146
14147
14148
14149
14150
14151
14152
14153
14154
14155
14156
14157
14158
14159
14160
14161
14162
14163
14164
14165
14166
14167
14168
14169
14170
14171
14172
14173
14174
14175
14176
14177
14178
14179
14180
14181
14182
14183
14184
14185
14186
14187
14188
14189
14190
14191
14192
14193
14194
14195
14196
14197
14198
14199
14200
14201
14202
14203
14204
14205
14206
14207
14208
14209
14210
14211
14212
14213
14214
14215
14216
14217
14218
14219
14220
14221
14222
14223
14224
14225
14226
14227
14228
14229
14230
14231
14232
14233
14234
14235
14236
14237
14238
14239
14240
14241
14242
14243
14244
14245
14246
14247
14248
14249
14250
14251
14252
14253
14254
14255
14256
14257
14258
14259
14260
14261
14262
14263
14264
14265
14266
14267
14268
14269
14270
14271

---------------------------------------------------------
----------------Auto generated code block----------------
---------------------------------------------------------

do
    local searchers = package.searchers or package.loaders
    local origin_seacher = searchers[2]
    searchers[2] = function(path)
        local files =
        {
------------------------
-- Modules part begin --
------------------------

["pl.xml"] = function()
--------------------
-- Module: 'pl.xml'
--------------------
--- XML LOM Utilities.
--
-- This implements some useful things on [LOM](http://matthewwild.co.uk/projects/luaexpat/lom.html) documents, such as returned by `lxp.lom.parse`.
-- In particular, it can convert LOM back into XML text, with optional pretty-printing control.
-- It is based on stanza.lua from [Prosody](http://hg.prosody.im/trunk/file/4621c92d2368/util/stanza.lua)
--
--     > d = xml.parse "<nodes><node id='1'>alice</node></nodes>"
--     > = d
--     <nodes><node id='1'>alice</node></nodes>
--     > = xml.tostring(d,'','  ')
--     <nodes>
--        <node id='1'>alice</node>
--     </nodes>
--
-- Can be used as a lightweight one-stop-shop for simple XML processing; a simple XML parser is included
-- but the default is to use `lxp.lom` if it can be found.
-- <pre>
-- Prosody IM
-- Copyright (C) 2008-2010 Matthew Wild
-- Copyright (C) 2008-2010 Waqas Hussain--
-- classic Lua XML parser by Roberto Ierusalimschy.
-- modified to output LOM format.
-- http://lua-users.org/wiki/LuaXml
-- </pre>
-- See @{06-data.md.XML|the Guide}
--
-- Dependencies: `pl.utils`
--
-- Soft Dependencies: `lxp.lom` (fallback is to use basic Lua parser)
-- @module pl.xml

local utils = require 'pl.utils'
local split         =   utils.split
local t_insert      =  table.insert
local t_concat      =  table.concat
local t_remove      =  table.remove
local s_match       =  string.match
local tostring      =      tostring
local setmetatable  =  setmetatable
local getmetatable  =  getmetatable
local pairs         =         pairs
local ipairs        =        ipairs
local type          =          type
local next          =          next
local print         =         print
local unpack        =  utils.unpack
local s_gsub        =   string.gsub
local s_sub         =    string.sub
local s_find        =   string.find
local pcall         =         pcall
local require       =       require


utils.raise_deprecation {
  source = "Penlight " .. utils._VERSION,
  message = "the contents of module 'pl.xml' has been deprecated, please use a more specialized library instead",
  version_removed = "2.0.0",
  deprecated_after = "1.11.0",
  no_trace = true,
}



local _M = {}
local Doc = { __type = "doc" };
Doc.__index = Doc;


local function is_text(s) return type(s) == 'string' end
local function is_tag(d) return type(d) == 'table' and is_text(d.tag) end



--- create a new document node.
-- @tparam string tag the tag name
-- @tparam[opt={}] table attr attributes (table of name-value pairs)
-- @return the Node object
-- @see xml.elem
-- @usage
-- local doc = xml.new("main", { hello = "world", answer = "42" })
-- print(doc)  -->  <main hello='world' answer='42'/>
function _M.new(tag, attr)
  if type(tag) ~= "string" then
    error("expected 'tag' to be a string value, got: " .. type(tag), 2)
  end
  attr = attr or {}
  if type(attr) ~= "table" then
    error("expected 'attr' to be a table value, got: " .. type(attr), 2)
  end

  local doc = { tag = tag, attr = attr, last_add = {}};
  return setmetatable(doc, Doc);
end


--- parse an XML document. By default, this uses lxp.lom.parse, but
-- falls back to basic_parse, or if `use_basic` is truthy
-- @param text_or_filename  file or string representation
-- @param is_file whether text_or_file is a file name or not
-- @param use_basic do a basic parse
-- @return a parsed LOM document with the document metatatables set
-- @return nil, error the error can either be a file error or a parse error
function _M.parse(text_or_filename, is_file, use_basic)
  local parser,status,lom
  if use_basic then
    parser = _M.basic_parse
  else
    status,lom = pcall(require,'lxp.lom')
    if not status then
      parser = _M.basic_parse
    else
      parser = lom.parse
    end
  end

  if is_file then
    local text_or_filename, err = utils.readfile(text_or_filename)
    if not text_or_filename then
      return nil, err
    end
  end

  local doc, err = parser(text_or_filename)
  if not doc then
    return nil, err
  end

  if lom then
    _M.walk(doc, false, function(_, d)
      setmetatable(d, Doc)
    end)
  end
  return doc
end


--- Create a Node with a set of children (text or Nodes) and attributes.
-- @tparam string tag a tag name
-- @tparam table|string items either a single child (text or Node), or a table where the hash
-- part is the attributes and the list part is the children (text or Nodes).
-- @return the new Node
-- @see xml.new
-- @see xml.tags
-- @usage
-- local doc = xml.elem("top", "hello world")                -- <top>hello world</top>
-- local doc = xml.elem("main", xml.new("child"))            -- <main><child/></main>
-- local doc = xml.elem("main", { "this ", "is ", "nice" })  -- <main>this is nice</main>
-- local doc = xml.elem("main", { xml.new "this",
--                                xml.new "is",
--                                xml.new "nice" })          -- <main><this/><is/><nice/></main>
-- local doc = xml.elem("main", { hello = "world" })         -- <main hello='world'/>
-- local doc = xml.elem("main", {
--   "prefix",
--   xml.elem("child", { "this ", "is ", "nice"}),
--   "postfix",
--   attrib = "value"
-- })   -- <main attrib='value'>prefix<child>this is nice</child>postfix</main>"
function _M.elem(tag, items)
  local s = _M.new(tag)
  if is_text(items) then items = {items} end
  if is_tag(items) then
    t_insert(s,items)
  elseif type(items) == 'table' then
    for k,v in pairs(items) do
      if is_text(k) then
        s.attr[k] = v
        t_insert(s.attr,k)
      else
        s[k] = v
      end
    end
  end
  return s
end


--- given a list of names, return a number of element constructors.
-- If passing a comma-separated string, then whitespace surrounding the values
-- will be stripped.
--
-- The returned constructor functions are a shortcut to `xml.elem` where you
-- no longer provide the tag-name, but only the `items` table.
-- @tparam string|table list a list of names, or a comma-separated string.
-- @return (multiple) constructor functions; `function(items)`. For the `items`
-- parameter see `xml.elem`.
-- @see xml.elem
-- @usage
-- local new_parent, new_child = xml.tags 'mom, kid'
-- doc = new_parent {new_child 'Bob', new_child 'Annie'}
-- -- <mom><kid>Bob</kid><kid>Annie</kid></mom>
function _M.tags(list)
  local ctors = {}
  if is_text(list) then
    list = split(list:match("^%s*(.-)%s*$"),'%s*,%s*')
  end
  for i,tag in ipairs(list) do
    local function ctor(items)
      return _M.elem(tag,items)
    end
    ctors[i] = ctor
  end
  return unpack(ctors)
end


--- Adds a document Node, at current position.
-- This updates the last inserted position to the new Node.
-- @tparam string tag the tag name
-- @tparam[opt={}] table attrs attributes (table of name-value pairs)
-- @return the current node (`self`)
-- @usage
-- local doc = xml.new("main")
-- doc:addtag("penlight", { hello = "world"})
-- doc:addtag("expat")  -- added to 'penlight' since position moved
-- print(doc)  -->  <main><penlight hello='world'><expat/></penlight></main>
function Doc:addtag(tag, attrs)
  local s = _M.new(tag, attrs)
  self:add_child(s)
  t_insert(self.last_add, s)
  return self
end


--- Adds a text node, at current position.
-- @tparam string text a string
-- @return the current node (`self`)
-- @usage
-- local doc = xml.new("main")
-- doc:text("penlight")
-- doc:text("expat")
-- print(doc)  -->  <main><penlightexpat</main>
function Doc:text(text)
  self:add_child(text)
  return self
end


--- Moves current position up one level.
-- @return the current node (`self`)
function Doc:up()
  t_remove(self.last_add)
  return self
end


--- Resets current position to top level.
-- Resets to the `self` node.
-- @return the current node (`self`)
function Doc:reset()
  local last_add = self.last_add
  for i = 1,#last_add do
    last_add[i] = nil
  end
  return self
end


--- Append a child to the currrent Node (ignoring current position).
-- @param child a child node (either text or a document)
-- @return the current node (`self`)
-- @usage
-- local doc = xml.new("main")
-- doc:add_direct_child("dog")
-- doc:add_direct_child(xml.new("child"))
-- doc:add_direct_child("cat")
-- print(doc)  -->  <main>dog<child/>cat</main>
function Doc:add_direct_child(child)
  t_insert(self, child)
  return self
end


--- Append a child at the current position (without changing position).
-- @param child a child node (either text or a document)
-- @return the current node (`self`)
-- @usage
-- local doc = xml.new("main")
-- doc:addtag("one")
-- doc:add_child(xml.new("item1"))
-- doc:add_child(xml.new("item2"))
-- doc:add_child(xml.new("item3"))
-- print(doc)  -->  <main><one><item1/><item2/><item3/></one></main>
function Doc:add_child(child)
  (self.last_add[#self.last_add] or self):add_direct_child(child)
  return self
end


--accessing attributes: useful not to have to expose implementation (attr)
--but also can allow attr to be nil in any future optimizations


--- Set attributes of a document node.
-- Will add/overwite values, but will not remove existing ones.
-- Operates on the Node itself, will not take position into account.
-- @tparam table t a table containing attribute/value pairs
-- @return the current node (`self`)
function Doc:set_attribs(t)
  -- TODO: keep array part in sync
  for k,v in pairs(t) do
    self.attr[k] = v
  end
  return self
end


--- Set a single attribute of a document node.
-- Operates on the Node itself, will not take position into account.
-- @param a attribute
-- @param v its value, pass in `nil` to delete the attribute
-- @return the current node (`self`)
function Doc:set_attrib(a,v)
  -- TODO: keep array part in sync
  self.attr[a] = v
  return self
end


--- Gets the attributes of a document node.
-- Operates on the Node itself, will not take position into account.
-- @return table with attributes (attribute/value pairs)
function Doc:get_attribs()
  return self.attr
end



local template_cache do
  local templ_cache = {}

  -- @param templ a template, a string being valid xml to be parsed, or a Node object
  function template_cache(templ)
    if is_text(templ) then
      if templ_cache[templ] then
        -- cache hit
        return templ_cache[templ]

      else
        -- parse and cache
        local ptempl, err = _M.parse(templ,false,true)
        if not ptempl then
          return nil, err
        end
        templ_cache[templ] = ptempl
        return ptempl
      end
    end

    if is_tag(templ) then
      return templ
    end

    return nil, "template is not a document"
  end
end


do
  local function is_data(data)
    return #data == 0 or type(data[1]) ~= 'table'
  end


  local function prepare_data(data)
    -- a hack for ensuring that $1 maps to first element of data, etc.
    -- Either this or could change the gsub call just below.
    for i,v in ipairs(data) do
      data[tostring(i)] = v
    end
  end

  --- create a substituted copy of a document,
  -- @param template may be a document or a string representation which will be parsed and cached
  -- @param data a table of name-value pairs or a list of such tables
  -- @return an XML document
  function Doc.subst(template, data)
    if type(data) ~= 'table' or not next(data) then
      return nil, "data must be a non-empty table"
    end

    if is_data(data) then
      prepare_data(data)
    end

    local templ, err = template_cache(template)
    if err then
      return nil, err
    end

    local function _subst(item)
      return _M.clone(templ, function(s)
        return s:gsub('%$(%w+)', item)
      end)
    end

    if is_data(data) then
      return _subst(data)
    end

    local list = {}
    for _, item in ipairs(data) do
      prepare_data(item)
      t_insert(list, _subst(item))
    end

    if data.tag then
      list = _M.elem(data.tag,list)
    end
    return list
  end
end


--- Return the first child with a given tag name (non-recursive).
-- @param tag the tag name
-- @return the child Node found or `nil` if not found
function Doc:child_with_name(tag)
  for _, child in ipairs(self) do
    if child.tag == tag then
      return child
    end
  end
end


do
  -- @param self document node to traverse
  -- @param tag tag-name to look for
  -- @param list array table to add the matching ones to
  -- @param recurse if truthy, recursivly search the node
  local function _children_with_name(self, tag, list, recurse)
    -- TODO: protect against recursion
    for _, child in ipairs(self) do
      if type(child) == 'table' then
        if child.tag == tag then
          t_insert(list, child)
        end
        if recurse then
          _children_with_name(child, tag, list, recurse)
        end
      end
    end
  end

  --- Returns all elements in a document that have a given tag.
  -- @tparam string tag a tag name
  -- @tparam[opt=false] boolean dont_recurse optionally only return the immediate children with this tag name
  -- @return a list of elements found, list will be empty if none was found.
  function Doc:get_elements_with_name(tag, dont_recurse)
    local res = {}
    _children_with_name(self, tag, res, not dont_recurse)
    return res
  end
end



--- Iterator over all children of a document node, including text nodes.
-- This function is not recursive, so returns only direct child nodes.
-- @return iterator that returns a single Node per iteration.
function Doc:children()
  local i = 0;
  return function (a)
    i = i + 1
    return a[i];
  end, self, i;
end


--- Return the first child element of a node, if it exists.
-- This will skip text nodes.
-- @return first child Node or `nil` if there is none.
function Doc:first_childtag()
  if #self == 0 then
    return
  end
  for _, t in ipairs(self) do
    if is_tag(t) then
      return t
    end
  end
end


--- Iterator that matches tag names, and a namespace (non-recursive).
-- @tparam[opt=nil] string tag tag names to return. Returns all tags if not provided.
-- @tparam[opt=nil] string xmlns the namespace value ('xmlns' attribute) to return. If not
-- provided will match all namespaces.
-- @return iterator that returns a single Node per iteration.
function Doc:matching_tags(tag, xmlns)
  -- TODO: this doesn't make sense??? namespaces are not "xmnls", as matched below
  -- but "xmlns:name"... so should be a string-prefix match if anything...
  xmlns = xmlns or self.attr.xmlns;
  local tags = self
  local next_i = 1
  local max_i = #tags
  local node
  return function ()
      for i = next_i, max_i do
        node = tags[i];
        if (not tag or node.tag == tag) and
           (not xmlns or xmlns == node.attr.xmlns) then
          next_i = i + 1
          return node
        end
      end
    end, tags, next_i
end


--- Iterator over all child tags of a document node. This will skip over
-- text nodes.
-- @return iterator that returns a single Node per iteration.
function Doc:childtags()
  local i = 0;
  return function (a)
    local v
      repeat
        i = i + 1
        v = self[i]
        if v and type(v) == 'table' then
          return v
        end
      until not v
    end, self[1], i;
end


--- Visit child Nodes of a node and call a function, possibly modifying the document.
-- Text elements will be skipped.
-- This is not recursive, so only direct children will be passed.
-- @tparam function callback a function with signature `function(node)`, passed the node.
-- The element will be updated with the returned value, or deleted if it returns `nil`.
function Doc:maptags(callback)
  local i = 1;

  while i <= #self do
    if is_tag(self[i]) then
      local ret = callback(self[i]);
      if ret == nil then
        -- remove it
        t_remove(self, i);

      else
        -- update it
        self[i] = ret;
        i = i + 1;
      end
    else
      i = i + 1
    end
  end

  return self;
end


do
  local escape_table = {
    ["'"] = "&apos;",
    ['"'] = "&quot;",
    ["<"] = "&lt;",
    [">"] = "&gt;",
    ["&"] = "&amp;",
  }

  --- Escapes a string for safe use in xml.
  -- Handles quotes(single+double), less-than, greater-than, and ampersand.
  -- @tparam string str string value to escape
  -- @return escaped string
  -- @usage
  -- local esc = xml.xml_escape([["'<>&]])  --> "&quot;&apos;&lt;&gt;&amp;"
  function _M.xml_escape(str)
    return (s_gsub(str, "['&<>\"]", escape_table))
  end
end
local xml_escape = _M.xml_escape

do
  local escape_table = {
    quot = '"',
    apos = "'",
    lt = "<",
    gt = ">",
    amp = "&",
  }

  --- Unescapes a string from xml.
  -- Handles quotes(single+double), less-than, greater-than, and ampersand.
  -- @tparam string str string value to unescape
  -- @return unescaped string
  -- @usage
  -- local unesc = xml.xml_escape("&quot;&apos;&lt;&gt;&amp;")  --> [["'<>&]]
  function _M.xml_unescape(str)
    return (str:gsub( "&(%a+);", escape_table))
  end
end
local xml_unescape = _M.xml_unescape

-- pretty printing
-- if indent, then put each new tag on its own line
-- if attr_indent, put each new attribute on its own line
local function _dostring(t, buf, parentns, block_indent, tag_indent, attr_indent)
  local nsid = 0
  local tag = t.tag

  local lf = ""
  if tag_indent then
    lf = '\n'..block_indent
  end

  local alf = " "
  if attr_indent then
    alf = '\n'..block_indent..attr_indent
  end

  t_insert(buf, lf.."<"..tag)

  local function write_attr(k,v)
    if s_find(k, "\1", 1, true) then
      nsid = nsid + 1
      local ns, attrk = s_match(k, "^([^\1]*)\1?(.*)$")
      t_insert(buf, " xmlns:ns"..nsid.."='"..xml_escape(ns).."' ".."ns"..nsid..":"..attrk.."='"..xml_escape(v).."'")

    elseif not (k == "xmlns" and v == parentns) then
      t_insert(buf, alf..k.."='"..xml_escape(v).."'");
    end
  end

  -- it's useful for testing to have predictable attribute ordering, if available
  if #t.attr > 0 then
    -- TODO: the key-value list is leading, what if they are not in-sync
    for _,k in ipairs(t.attr) do
      write_attr(k,t.attr[k])
    end
  else
    for k, v in pairs(t.attr) do
      write_attr(k,v)
    end
  end

  local len = #t
  local has_children

  if len == 0 then
    t_insert(buf, attr_indent and '\n'..block_indent.."/>" or "/>")

  else
    t_insert(buf, ">");

    for n = 1, len do
      local child = t[n]

      if child.tag then
        has_children = true
        _dostring(child, buf, t.attr.xmlns, block_indent and block_indent..tag_indent, tag_indent, attr_indent)

      else
        -- text element
        t_insert(buf, xml_escape(child))
      end
    end

    t_insert(buf, (has_children and lf or '').."</"..tag..">");
  end
end

--- Function to pretty-print an XML document.
-- @param doc an XML document
-- @tparam[opt] string|int b_ind an initial block-indent (required when `t_ind` is set)
-- @tparam[opt] string|int t_ind an tag-indent for each level (required when `a_ind` is set)
-- @tparam[opt] string|int a_ind if given, indent each attribute pair and put on a separate line
-- @tparam[opt] string|bool xml_preface force prefacing with default or custom <?xml...>, if truthy then `&lt;?xml version='1.0'?&gt;` will be used as default.
-- @return a string representation
-- @see Doc:tostring
function _M.tostring(doc, b_ind, t_ind, a_ind, xml_preface)
  local buf = {}

  if type(b_ind) == "number" then b_ind = (" "):rep(b_ind) end
  if type(t_ind) == "number" then t_ind = (" "):rep(t_ind) end
  if type(a_ind) == "number" then a_ind = (" "):rep(a_ind) end

  if xml_preface then
    if type(xml_preface) == "string" then
      buf[1] = xml_preface
    else
      buf[1] = "<?xml version='1.0'?>"
    end
  end

  _dostring(doc, buf, nil, b_ind, t_ind, a_ind, xml_preface)

  return t_concat(buf)
end


Doc.__tostring = _M.tostring


--- Method to pretty-print an XML document.
-- Invokes `xml.tostring`.
-- @tparam[opt] string|int b_ind an initial indent (required when `t_ind` is set)
-- @tparam[opt] string|int t_ind an indent for each level (required when `a_ind` is set)
-- @tparam[opt] string|int a_ind if given, indent each attribute pair and put on a separate line
-- @tparam[opt="&lt;?xml version='1.0'?&gt;"] string xml_preface force prefacing with default or custom <?xml...>
-- @return a string representation
-- @see xml.tostring
function Doc:tostring(b_ind, t_ind, a_ind, xml_preface)
  return _M.tostring(self, b_ind, t_ind, a_ind, xml_preface)
end


--- get the full text value of an element.
-- @return a single string with all text elements concatenated
-- @usage
-- local doc = xml.new("main")
-- doc:text("one")
-- doc:add_child(xml.elem "two")
-- doc:text("three")
--
-- local t = doc:get_text()    -->  "onethree"
function Doc:get_text()
  local res = {}
  for i,el in ipairs(self) do
    if is_text(el) then t_insert(res,el) end
  end
  return t_concat(res);
end


do
  local function _copy(object, kind, parent, strsubst, lookup_table)
    if type(object) ~= "table" then
      if strsubst and is_text(object) then
        return strsubst(object, kind, parent)
      else
        return object
      end
    end

    if lookup_table[object] then
      error("recursion detected")
    end
    lookup_table[object] = true

    local new_table = {}
    lookup_table[object] = new_table

    local tag = object.tag
    new_table.tag = _copy(tag, '*TAG', parent, strsubst, lookup_table)

    if object.attr then
      local res = {}
      for attr, value in pairs(object.attr) do
        if type(attr) == "string" then
          res[attr] = _copy(value, attr, object, strsubst, lookup_table)
        end
      end
      new_table.attr = res
    end

    for index = 1, #object do
      local v = _copy(object[index], '*TEXT', object, strsubst, lookup_table)
      t_insert(new_table,v)
    end

    return setmetatable(new_table, getmetatable(object))
  end

  --- Returns a copy of a document.
  -- The `strsubst` parameter is a callback with signature `function(object, kind, parent)`.
  --
  -- Param `kind` has the following values, and parameters:
  --
  -- - `"*TAG"`: `object` is the tag-name, `parent` is the Node object. Returns the new tag name.
  --
  -- - `"*TEXT"`: `object` is the text-element, `parent` is the Node object. Returns the new text value.
  --
  -- - other strings not prefixed with `*`: `kind` is the attribute name, `object` is the
  --   attribute value, `parent` is the Node object. Returns the new attribute value.
  --
  -- @tparam Node|string doc a Node object or string (text node)
  -- @tparam[opt] function strsubst an optional function for handling string copying
  -- which could do substitution, etc.
  -- @return copy of the document
  -- @see Doc:filter
  function _M.clone(doc, strsubst)
    return _copy(doc, nil, nil, strsubst, {})
  end
end


--- Returns a copy of a document.
-- This is the method version of `xml.clone`.
-- @see xml.clone
-- @name Doc:filter
-- @tparam[opt] function strsubst an optional function for handling string copying
Doc.filter = _M.clone -- also available as method

do
  local function _compare(t1, t2, recurse_check)

    local ty1 = type(t1)
    local ty2 = type(t2)

    if ty1 ~= ty2 then
      return false, 'type mismatch'
    end

    if ty1 == 'string' then
      if t1 == t2 then
        return true
      else
        return false, 'text '..t1..' ~= text '..t2
      end
    end

    if ty1 ~= 'table' or ty2 ~= 'table' then
      return false, 'not a document'
    end

    if recurse_check[t1] then
      return false, "recursive document"
    end
    recurse_check[t1] = true

    if t1.tag ~= t2.tag then
      return false, 'tag  '..t1.tag..' ~= tag '..t2.tag
    end

    if #t1 ~= #t2 then
      return false, 'size '..#t1..' ~= size '..#t2..' for tag '..t1.tag
    end

    -- compare attributes
    for k,v in pairs(t1.attr) do
      local t2_value = t2.attr[k]
      if type(k) == "string" then
        if t2_value ~= v then return false, 'mismatch attrib' end
      else
        if t2_value ~= nil and t2_value ~= v then return false, "mismatch attrib order" end
      end
    end
    for k,v in pairs(t2.attr) do
      local t1_value = t1.attr[k]
      if type(k) == "string" then
        if t1_value ~= v then return false, 'mismatch attrib' end
      else
        if t1_value ~= nil and t1_value ~= v then return false, "mismatch attrib order" end
      end
    end

    -- compare children
    for i = 1, #t1 do
      local ok, err = _compare(t1[i], t2[i], recurse_check)
      if not ok then
        return ok, err
      end
    end
    return true
  end

  --- Compare two documents or elements.
  -- Equality is based on tag, child nodes (text and tags), attributes and order
  -- of those (order only fails if both are given, and not equal).
  -- @tparam Node|string t1 a Node object or string (text node)
  -- @tparam Node|string t2 a Node object or string (text node)
  -- @treturn boolean `true` when the Nodes are equal.
  function _M.compare(t1,t2)
    return _compare(t1, t2, {})
  end
end


--- is this value a document element?
-- @param d any value
-- @treturn boolean `true` if it is a `table` with property `tag` being a string value.
-- @name is_tag
_M.is_tag = is_tag


do
  local function _walk(doc, depth_first, operation, recurse_check)
    if not depth_first then operation(doc.tag, doc) end
    for _,d in ipairs(doc) do
      if is_tag(d) then
        assert(not recurse_check[d], "recursion detected")
        recurse_check[d] = true
        _walk(d, depth_first, operation, recurse_check)
      end
    end
    if depth_first then operation(doc.tag, doc) end
  end

  --- Calls a function recursively over Nodes in the document.
  -- Will only call on tags, it will skip text nodes.
  -- The function signature for `operation` is `function(tag_name, Node)`.
  -- @tparam Node|string doc a Node object or string (text node)
  -- @tparam boolean depth_first visit child nodes first, then the current node
  -- @tparam function operation a function which will receive the current tag name and current node.
  function _M.walk(doc, depth_first, operation)
    return _walk(doc, depth_first, operation, {})
  end
end


local html_empty_elements = { --lists all HTML empty (void) elements
    br      = true,
    img     = true,
    meta    = true,
    frame   = true,
    area    = true,
    hr      = true,
    base    = true,
    col     = true,
    link    = true,
    input   = true,
    option  = true,
    param   = true,
    isindex = true,
    embed = true,
}

--- Parse a well-formed HTML file as a string.
-- Tags are case-insenstive, DOCTYPE is ignored, and empty elements can be .. empty.
-- @param s the HTML
function _M.parsehtml(s)
    return _M.basic_parse(s,false,true)
end

--- Parse a simple XML document using a pure Lua parser based on Robero Ierusalimschy's original version.
-- @param s the XML document to be parsed.
-- @param all_text  if true, preserves all whitespace. Otherwise only text containing non-whitespace is included.
-- @param html if true, uses relaxed HTML rules for parsing
function _M.basic_parse(s, all_text, html)
    local stack = {}
    local top = {}

    local function parseargs(s)
      local arg = {}
      s:gsub("([%w:%-_]+)%s*=%s*([\"'])(.-)%2", function (w, _, a)
        if html then w = w:lower() end
        arg[w] = xml_unescape(a)
      end)
      if html then
        s:gsub("([%w:%-_]+)%s*=%s*([^\"']+)%s*", function (w, a)
          w = w:lower()
          arg[w] = xml_unescape(a)
        end)
      end
      return arg
    end

    t_insert(stack, top)
    local ni,c,label,xarg, empty, _, istart
    local i = 1
    local j
    -- we're not interested in <?xml version="1.0"?>
    _,istart = s_find(s,'^%s*<%?[^%?]+%?>%s*')
    if not istart then -- or <!DOCTYPE ...>
        _,istart = s_find(s,'^%s*<!DOCTYPE.->%s*')
    end
    if istart then i = istart+1 end
    while true do
        ni,j,c,label,xarg, empty = s_find(s, "<([%/!]?)([%w:%-_]+)(.-)(%/?)>", i)
        if not ni then break end
        if c == "!" then -- comment
            -- case where there's no space inside comment
            if not (label:match '%-%-$' and xarg == '') then
                if xarg:match '%-%-$' then -- we've grabbed it all
                    j = j - 2
                end
                -- match end of comment
                _,j = s_find(s, "-->", j, true)
            end
        else
            local text = s_sub(s, i, ni-1)
            if html then
                label = label:lower()
                if html_empty_elements[label] then empty = "/" end
            end
            if all_text or not s_find(text, "^%s*$") then
                t_insert(top, xml_unescape(text))
            end
            if empty == "/" then  -- empty element tag
                t_insert(top, setmetatable({tag=label, attr=parseargs(xarg), empty=1},Doc))
            elseif c == "" then   -- start tag
                top = setmetatable({tag=label, attr=parseargs(xarg)},Doc)
                t_insert(stack, top)   -- new level
            else  -- end tag
                local toclose = t_remove(stack)  -- remove top
                top = stack[#stack]
                if #stack < 1 then
                    error("nothing to close with "..label..':'..text)
                end
                if toclose.tag ~= label then
                    error("trying to close "..toclose.tag.." with "..label.." "..text)
                end
                t_insert(top, toclose)
            end
        end
        i = j+1
    end
    local text = s_sub(s, i)
    if all_text or  not s_find(text, "^%s*$") then
        t_insert(stack[#stack], xml_unescape(text))
    end
    if #stack > 1 then
        error("unclosed "..stack[#stack].tag)
    end
    local res = stack[1]
    return is_text(res[1]) and res[2] or res[1]
end

do
  local match do

    local function empty(attr) return not attr or not next(attr) end

    local append_capture do
      -- returns the key,value pair from a table if it has exactly one entry
      local function has_one_element(t)
          local key,value = next(t)
          if next(t,key) ~= nil then return false end
          return key,value
      end

      function append_capture(res,tbl)
          if not empty(tbl) then -- no point in capturing empty tables...
              local key
              if tbl._ then  -- if $_ was set then it is meant as the top-level key for the captured table
                  key = tbl._
                  tbl._ = nil
                  if empty(tbl) then return end
              end
              -- a table with only one pair {[0]=value} shall be reduced to that value
              local numkey,val = has_one_element(tbl)
              if numkey == 0 then tbl = val end
              if key then
                  res[key] = tbl
              else -- otherwise, we append the captured table
                  t_insert(res,tbl)
              end
          end
      end
    end

    local function make_number(pat)
        if pat:find '^%d+$' then -- $1 etc means use this as an array location
            pat = tonumber(pat)
        end
        return pat
    end

    local function capture_attrib(res,pat,value)
        pat = make_number(pat:sub(2))
        res[pat] = value
        return true
    end

    function match(d,pat,res,keep_going)
        local ret = true
        if d == nil then d = '' end --return false end
        -- attribute string matching is straight equality, except if the pattern is a $ capture,
        -- which always succeeds.
        if is_text(d) then
            if not is_text(pat) then return false end
            if _M.debug then print(d,pat) end
            if pat:find '^%$' then
                return capture_attrib(res,pat,d)
            else
                return d == pat
            end
        else
        if _M.debug then print(d.tag,pat.tag) end
            -- this is an element node. For a match to succeed, the attributes must
            -- match as well.
            -- a tagname in the pattern ending with '-' is a wildcard and matches like an attribute
            local tagpat = pat.tag:match '^(.-)%-$'
            if tagpat then
                tagpat = make_number(tagpat)
                res[tagpat] = d.tag
            end
            if d.tag == pat.tag or tagpat then

                if not empty(pat.attr) then
                    if empty(d.attr) then ret =  false
                    else
                        for prop,pval in pairs(pat.attr) do
                            local dval = d.attr[prop]
                            if not match(dval,pval,res) then ret = false;  break end
                        end
                    end
                end
                -- the pattern may have child nodes. We match partially, so that {P1,P2} shall match {X,P1,X,X,P2,..}
                if ret and #pat > 0 then
                    local i,j = 1,1
                    local function next_elem()
                        j = j + 1  -- next child element of data
                        if is_text(d[j]) then j = j + 1 end
                        return j <= #d
                    end
                    repeat
                        local p = pat[i]
                        -- repeated {{<...>}} patterns  shall match one or more elements
                        -- so e.g. {P+} will match {X,X,P,P,X,P,X,X,X}
                        if is_tag(p) and p.repeated then
                            local found
                            repeat
                                local tbl = {}
                                ret = match(d[j],p,tbl,false)
                                if ret then
                                    found = false --true
                                    append_capture(res,tbl)
                                end
                            until not next_elem() or (found and not ret)
                            i = i + 1
                        else
                            ret = match(d[j],p,res,false)
                            if ret then i = i + 1 end
                        end
                    until not next_elem() or i > #pat -- run out of elements or patterns to match
                    -- if every element in our pattern matched ok, then it's been a successful match
                    if i > #pat then return true end
                end
                if ret then return true end
            else
                ret = false
            end
            -- keep going anyway - look at the children!
            if keep_going then
                for child in d:childtags() do
                    ret = match(child,pat,res,keep_going)
                    if ret then break end
                end
            end
        end
        return ret
    end
  end

  --- does something...
  function Doc:match(pat)
      local err
      pat,err = template_cache(pat)
      if not pat then return nil, err end
      _M.walk(pat,false,function(_,d)
          if is_text(d[1]) and is_tag(d[2]) and is_text(d[3]) and
            d[1]:find '%s*{{' and d[3]:find '}}%s*' then
            t_remove(d,1)
            t_remove(d,2)
            d[1].repeated = true
          end
      end)

      local res = {}
      local ret = match(self,pat,res,true)
      return res,ret
  end
end


return _M


end,

["pl.app"] = function()
--------------------
-- Module: 'pl.app'
--------------------
--- Application support functions.
-- See @{01-introduction.md.Application_Support|the Guide}
--
-- Dependencies: `pl.utils`, `pl.path`
-- @module pl.app

local io,package,require = _G.io, _G.package, _G.require
local utils = require 'pl.utils'
local path = require 'pl.path'

local app = {}

--- return the name of the current script running.
-- The name will be the name as passed on the command line
-- @return string filename
function app.script_name()
    if _G.arg and _G.arg[0] then
        return _G.arg[0]
    end
    return utils.raise("No script name found")
end

--- prefixes the current script's path to the Lua module path.
-- Applies to both the source and the binary module paths. It makes it easy for
-- the main file of a multi-file program to access its modules in the same directory.
-- `base` allows these modules to be put in a specified subdirectory, to allow for
-- cleaner deployment and resolve potential conflicts between a script name and its
-- library directory.
--
-- Note: the path is prefixed, so it is searched first when requiring modules.
-- @string base optional base directory (absolute, or relative path).
-- @treturn string the current script's path with a trailing slash
function app.require_here (base)
    local p = path.dirname(app.script_name())
    if not path.isabs(p) then
        p = path.join(path.currentdir(),p)
    end
    if p:sub(-1,-1) ~= path.sep then
        p = p..path.sep
    end
    if base then
        if path.is_windows then
            base = base:gsub('/','\\')
        end
        if path.isabs(base) then
            p = base .. path.sep
        else
            p = p..base..path.sep
        end
    end
    local so_ext = path.is_windows and 'dll' or 'so'
    local lsep = package.path:find '^;' and '' or ';'
    local csep = package.cpath:find '^;' and '' or ';'
    package.path = ('%s?.lua;%s?%sinit.lua%s%s'):format(p,p,path.sep,lsep,package.path)
    package.cpath = ('%s?.%s%s%s'):format(p,so_ext,csep,package.cpath)
    return p
end

--- return a suitable path for files private to this application.
-- These will look like '~/.SNAME/file', with '~' as with expanduser and
-- SNAME is the name of the script without .lua extension.
-- If the directory does not exist, it will be created.
-- @string file a filename (w/out path)
-- @return a full pathname, or nil
-- @return cannot create directory error
-- @usage
-- -- when run from a script called 'testapp' (on Windows):
-- local app = require 'pl.app'
-- print(app.appfile 'test.txt')
-- -- C:\Documents and Settings\steve\.testapp\test.txt
function app.appfile(file)
    local sfullname, err = app.script_name()
    if not sfullname then return utils.raise(err) end
    local sname = path.basename(sfullname)
    local name = path.splitext(sname)
    local dir = path.join(path.expanduser('~'),'.'..name)
    if not path.isdir(dir) then
        local ret = path.mkdir(dir)
        if not ret then return utils.raise('cannot create '..dir) end
    end
    return path.join(dir,file)
end

--- return string indicating operating system.
-- @return 'Windows','OSX' or whatever uname returns (e.g. 'Linux')
function app.platform()
    if path.is_windows then
        return 'Windows'
    else
        local f = io.popen('uname')
        local res = f:read()
        if res == 'Darwin' then res = 'OSX' end
        f:close()
        return res
    end
end

--- return the full command-line used to invoke this script.
-- It will not include the scriptname itself, see `app.script_name`.
-- @return command-line
-- @return name of Lua program used
-- @usage
-- -- execute:  lua -lluacov -e 'print(_VERSION)' myscript.lua
--
-- -- myscript.lua
-- print(require("pl.app").lua())  --> "lua -lluacov -e 'print(_VERSION)'", "lua"
function app.lua()
    local args = _G.arg
    if not args then
        return utils.raise "not in a main program"
    end

    local cmd = {}
    local i = -1
    while true do
        table.insert(cmd, 1, args[i])
        if not args[i-1] then
            return utils.quote_arg(cmd), args[i]
        end
        i = i - 1
    end
end

--- parse command-line arguments into flags and parameters.
-- Understands GNU-style command-line flags; short (`-f`) and long (`--flag`).
--
-- These may be given a value with either '=' or ':' (`-k:2`,`--alpha=3.2`,`-n2`),
-- a number value can be given without a space. If the flag is marked
-- as having a value, then a space-separated value is also accepted (`-i hello`),
-- see the `flags_with_values` argument).
--
-- Multiple short args can be combined like so: ( `-abcd`).
--
-- When specifying the `flags_valid` parameter, its contents can also contain
-- aliasses, to convert short/long flags to the same output name. See the
-- example below.
--
-- Note: if a flag is repeated, the last value wins.
-- @tparam {string} args an array of strings (default is the global `arg`)
-- @tab flags_with_values any flags that take values, either list or hash
-- table e.g. `{ out=true }` or `{ "out" }`.
-- @tab flags_valid (optional) flags that are valid, either list or hashtable.
-- If not given, everything
-- will be accepted(everything in `flags_with_values` will automatically be allowed)
-- @return a table of flags (flag=value pairs)
-- @return an array of parameters
-- @raise if args is nil, then the global `args` must be available!
-- @usage
-- -- Simple form:
-- local flags, params = app.parse_args(nil,
--      { "hello", "world" },  -- list of flags taking values
--      { "l", "a", "b"})      -- list of allowed flags (value ones will be added)
--
-- -- More complex example using aliasses:
-- local valid = {
--     long = "l",           -- if 'l' is specified, it is reported as 'long'
--     new = { "n", "old" }, -- here both 'n' and 'old' will go into 'new'
-- }
-- local values = {
--     "value",   -- will automatically be added to the allowed set of flags
--     "new",     -- will mark 'n' and 'old' as requiring a value as well
-- }
-- local flags, params = app.parse_args(nil, values, valid)
--
-- -- command:  myapp.lua -l --old:hello --value world param1 param2
-- -- will yield:
-- flags = {
--     long = true,     -- input from 'l'
--     new = "hello",   -- input from 'old'
--     value = "world", -- allowed because it was in 'values', note: space separated!
-- }
-- params = {
--     [1] = "param1"
--     [2] = "param2"
-- }
function app.parse_args (args,flags_with_values, flags_valid)
    if not args then
        args = _G.arg
        if not args then utils.raise "Not in a main program: 'arg' not found" end
    end

    local with_values = {}
    for k,v in pairs(flags_with_values or {}) do
        if type(k) == "number" then
            k = v
        end
        with_values[k] = true
    end

    local valid
    if not flags_valid then
        -- if no allowed flags provided, we create a table that always returns
        -- the keyname, no matter what you look up
        valid = setmetatable({},{ __index = function(_, key) return key end })
    else
        valid = {}
        for k,aliasses in pairs(flags_valid) do
            if type(k) == "number" then         -- array/list entry
                k = aliasses
            end
            if type(aliasses) == "string" then  -- single alias
                aliasses = { aliasses }
            end
            if type(aliasses) == "table" then   -- list of aliasses
                -- it's the alternate name, so add the proper mappings
                for i, alias in ipairs(aliasses) do
                    valid[alias] = k
                end
            end
            valid[k] = k
        end
        do
            local new_with_values = {}  -- needed to prevent "invalid key to 'next'" error
            for k,v in pairs(with_values) do
                if not valid[k] then
                    valid[k] = k   -- add the with_value entry as a valid one
                    new_with_values[k] = true
                else
                    new_with_values[valid[k]] = true  --set, but by its alias
                end
            end
            with_values = new_with_values
        end
    end

    -- now check that all flags with values are reported as such under all
    -- of their aliasses
    for k, main_alias in pairs(valid) do
        if with_values[main_alias] then
            with_values[k] = true
        end
    end

    local _args = {}
    local flags = {}
    local i = 1
    while i <= #args do
        local a = args[i]
        local v = a:match('^-(.+)')
        local is_long
        if not v then
            -- we have a parameter
            _args[#_args+1] = a
        else
            -- it's a flag
            if v:find '^-' then
                is_long = true
                v = v:sub(2)
            end
            if with_values[v] then
                if i == #args or args[i+1]:find '^-' then
                    return utils.raise ("no value for '"..v.."'")
                end
                flags[valid[v]] = args[i+1]
                i = i + 1
            else
                -- a value can also be indicated with = or :
                local var,val =  utils.splitv (v,'[=:]', false, 2)
                var = var or v
                val = val or true
                if not is_long then
                    if #var > 1 then
                        if var:find '.%d+' then -- short flag, number value
                            val = var:sub(2)
                            var = var:sub(1,1)
                        else -- multiple short flags
                            for i = 1,#var do
                                local f = var:sub(i,i)
                                if not valid[f] then
                                    return utils.raise("unknown flag '"..f.."'")
                                else
                                    f = valid[f]
                                end
                                flags[f] = true
                            end
                            val = nil -- prevents use of var as a flag below
                        end
                    else  -- single short flag (can have value, defaults to true)
                        val = val or true
                    end
                end
                if val then
                    if not valid[var] then
                        return utils.raise("unknown flag '"..var.."'")
                    else
                        var = valid[var]
                    end
                    flags[var] = val
                end
            end
        end
        i = i + 1
    end
    return flags,_args
end

return app

end,

["pl.array2d"] = function()
--------------------
-- Module: 'pl.array2d'
--------------------
--- Operations on two-dimensional arrays.
-- See @{02-arrays.md.Operations_on_two_dimensional_tables|The Guide}
--
-- The size of the arrays is determined by using the length operator `#` hence
-- the module is not `nil` safe, and the usual precautions apply.
--
-- Note: all functions taking `i1,j1,i2,j2` as arguments will normalize the
-- arguments using `default_range`.
--
-- Dependencies: `pl.utils`, `pl.tablex`, `pl.types`
-- @module pl.array2d

local tonumber,tostring,io,ipairs,string,table =
    _G.tonumber,_G.tostring,_G.io,_G.ipairs,_G.string,_G.table
local setmetatable,getmetatable = setmetatable,getmetatable

local tablex = require 'pl.tablex'
local utils = require 'pl.utils'
local types = require 'pl.types'
local imap,tmap,reduce,keys,tmap2,tset,index_by = tablex.imap,tablex.map,tablex.reduce,tablex.keys,tablex.map2,tablex.set,tablex.index_by
local remove = table.remove
local splitv,fprintf,assert_arg = utils.splitv,utils.fprintf,utils.assert_arg
local byte = string.byte
local stdout = io.stdout
local min = math.min


local array2d = {}

local function obj (int,out)
    local mt = getmetatable(int)
    if mt then
        setmetatable(out,mt)
    end
    return out
end

local function makelist (res)
    return setmetatable(res, require('pl.List'))
end

--- return the row and column size.
-- Size is calculated using the Lua length operator #, so usual precautions
-- regarding `nil` values apply.
-- @array2d a a 2d array
-- @treturn int number of rows (`#a`)
-- @treturn int number of cols (`#a[1]`)
function array2d.size (a)
    assert_arg(1,a,'table')
    return #a,#a[1]
end

do
    local function index (t,k)
        return t[k]
    end

    --- extract a column from the 2D array.
    -- @array2d a 2d array
    -- @param j column index
    -- @return 1d array
    function array2d.column (a,j)
        assert_arg(1,a,'table')
        return makelist(imap(index,a,j))
    end
end
local column = array2d.column

--- extract a row from the 2D array.
-- Added in line with `column`, for read-only purposes directly
-- accessing a[i] is more performant.
-- @array2d a 2d array
-- @param i row index
-- @return 1d array (copy of the row)
function array2d.row(a,i)
    assert_arg(1,a,'table')
    local row = a[i]
    local r = {}
    for n,v in ipairs(row) do
        r[n] = v
    end
    return makelist(r)
end

--- map a function over a 2D array
-- @func f a function of at least one argument
-- @array2d a 2d array
-- @param arg an optional extra argument to be passed to the function.
-- @return 2d array
function array2d.map (f,a,arg)
    assert_arg(2,a,'table')
    f = utils.function_arg(1,f)
    return obj(a,imap(function(row) return imap(f,row,arg) end, a))
end

--- reduce the rows using a function.
-- @func f a binary function
-- @array2d a 2d array
-- @return 1d array
-- @see pl.tablex.reduce
function array2d.reduce_rows (f,a)
    assert_arg(1,a,'table')
    return tmap(function(row) return reduce(f,row) end, a)
end

--- reduce the columns using a function.
-- @func f a binary function
-- @array2d a 2d array
-- @return 1d array
-- @see pl.tablex.reduce
function array2d.reduce_cols (f,a)
    assert_arg(1,a,'table')
    return tmap(function(c) return reduce(f,column(a,c)) end, keys(a[1]))
end

--- reduce a 2D array into a scalar, using two operations.
-- @func opc operation to reduce the final result
-- @func opr operation to reduce the rows
-- @param a 2D array
function array2d.reduce2 (opc,opr,a)
    assert_arg(3,a,'table')
    local tmp = array2d.reduce_rows(opr,a)
    return reduce(opc,tmp)
end

--- map a function over two arrays.
-- They can be both or either 2D arrays
-- @func f function of at least two arguments
-- @int ad order of first array (`1` if `a` is a list/array, `2` if it is a 2d array)
-- @int bd order of second array (`1` if `b` is a list/array, `2` if it is a 2d array)
-- @tab a 1d or 2d array
-- @tab b 1d or 2d array
-- @param arg optional extra argument to pass to function
-- @return 2D array, unless both arrays are 1D
function array2d.map2 (f,ad,bd,a,b,arg)
    assert_arg(1,a,'table')
    assert_arg(2,b,'table')
    f = utils.function_arg(1,f)
    if ad == 1 and bd == 2 then
        return imap(function(row)
            return tmap2(f,a,row,arg)
        end, b)
    elseif ad == 2 and bd == 1 then
        return imap(function(row)
            return tmap2(f,row,b,arg)
        end, a)
    elseif ad == 1 and bd == 1 then
        return tmap2(f,a,b)
    elseif ad == 2 and bd == 2 then
        return tmap2(function(rowa,rowb)
            return tmap2(f,rowa,rowb,arg)
        end, a,b)
    end
end

--- cartesian product of two 1d arrays.
-- @func f a function of 2 arguments
-- @array t1 a 1d table
-- @array t2 a 1d table
-- @return 2d table
-- @usage product('..',{1,2},{'a','b'}) == {{'1a','2a'},{'1b','2b'}}
function array2d.product (f,t1,t2)
    f = utils.function_arg(1,f)
    assert_arg(2,t1,'table')
    assert_arg(3,t2,'table')
    local res = {}
    for i,v in ipairs(t2) do
        res[i] = tmap(f,t1,v)
    end
    return res
end

--- flatten a 2D array.
-- (this goes over columns first.)
-- @array2d t 2d table
-- @return a 1d table
-- @usage flatten {{1,2},{3,4},{5,6}} == {1,2,3,4,5,6}
function array2d.flatten (t)
    local res = {}
    local k = 1
    local rows, cols = array2d.size(t)
    for r = 1, rows do
        local row = t[r]
        for c = 1, cols do
            res[k] = row[c]
            k = k + 1
        end
    end
    return makelist(res)
end

--- reshape a 2D array. Reshape the aray by specifying a new nr of rows.
-- @array2d t 2d array
-- @int nrows new number of rows
-- @bool co use column-order (Fortran-style) (default false)
-- @return a new 2d array
function array2d.reshape (t,nrows,co)
    local nr,nc = array2d.size(t)
    local ncols = nr*nc / nrows
    local res = {}
    local ir,ic = 1,1
    for i = 1,nrows do
        local row = {}
        for j = 1,ncols do
            row[j] = t[ir][ic]
            if not co then
                ic = ic + 1
                if ic > nc then
                    ir = ir + 1
                    ic = 1
                end
            else
                ir = ir + 1
                if ir > nr then
                    ic = ic + 1
                    ir = 1
                end
            end
        end
        res[i] = row
    end
    return obj(t,res)
end

--- transpose a 2D array.
-- @array2d t 2d array
-- @return a new 2d array
function array2d.transpose(t)
  assert_arg(1,t,'table')
  local _, c = array2d.size(t)
  return array2d.reshape(t,c,true)
end

--- swap two rows of an array.
-- @array2d t a 2d array
-- @int i1 a row index
-- @int i2 a row index
-- @return t (same, modified 2d array)
function array2d.swap_rows (t,i1,i2)
    assert_arg(1,t,'table')
    t[i1],t[i2] = t[i2],t[i1]
    return t
end

--- swap two columns of an array.
-- @array2d t a 2d array
-- @int j1 a column index
-- @int j2 a column index
-- @return t (same, modified 2d array)
function array2d.swap_cols (t,j1,j2)
    assert_arg(1,t,'table')
    for _, row in ipairs(t) do
        row[j1],row[j2] = row[j2],row[j1]
    end
    return t
end

--- extract the specified rows.
-- @array2d t 2d array
-- @tparam {int} ridx a table of row indices
-- @return a new 2d array with the extracted rows
function array2d.extract_rows (t,ridx)
    return obj(t,index_by(t,ridx))
end

--- extract the specified columns.
-- @array2d t 2d array
-- @tparam {int} cidx a table of column indices
-- @return a new 2d array with the extracted colums
function array2d.extract_cols (t,cidx)
    assert_arg(1,t,'table')
    local res = {}
    for i = 1,#t do
        res[i] = index_by(t[i],cidx)
    end
    return obj(t,res)
end

--- remove a row from an array.
-- @function array2d.remove_row
-- @array2d t a 2d array
-- @int i a row index
array2d.remove_row = remove

--- remove a column from an array.
-- @array2d t a 2d array
-- @int j a column index
function array2d.remove_col (t,j)
    assert_arg(1,t,'table')
    for i = 1,#t do
        remove(t[i],j)
    end
end

do
    local function _parse (s)
        local r, c = s:match 'R(%d+)C(%d+)'
        if r then
            r,c = tonumber(r),tonumber(c)
            return r,c
        end
        c,r = s:match '(%a+)(%d+)'
        if c then
            local cv = 0
            for i = 1, #c do
              cv = cv * 26 + byte(c:sub(i,i)) - byte 'A' + 1
            end
            return tonumber(r), cv
        end
        error('bad cell specifier: '..s)
    end

    --- parse a spreadsheet range or cell.
    -- The range/cell can be specified either as 'A1:B2' or 'R1C1:R2C2' or for
    -- single cells as 'A1' or 'R1C1'.
    -- @string s a range (case insensitive).
    -- @treturn int start row
    -- @treturn int start col
    -- @treturn int end row (or `nil` if the range was a single cell)
    -- @treturn int end col (or `nil` if the range was a single cell)
    function array2d.parse_range (s)
        assert_arg(1,s,'string')
        s = s:upper()
        if s:find ':' then
            local start,finish = splitv(s,':')
            local i1,j1 = _parse(start)
            local i2,j2 = _parse(finish)
            return i1,j1,i2,j2
        else -- single value
            local i,j = _parse(s)
            return i,j
        end
    end
end

--- get a slice of a 2D array.
-- Same as `slice`.
-- @see slice
function array2d.range (...)
    return array2d.slice(...)
end

local default_range do
    local function norm_value(v, max)
        if not v then return v end
        if v < 0 then
            v = max + v + 1
        end
        if v < 1 then v = 1 end
        if v > max then v = max end
        return v
    end

    --- normalizes coordinates to valid positive entries and defaults.
    -- Negative indices will be counted from the end, too low, or too high
    -- will be limited by the array sizes.
    -- @array2d t a 2D array
    -- @tparam[opt=1] int|string i1 start row or spreadsheet range passed to `parse_range`
    -- @tparam[opt=1] int j1 start col
    -- @tparam[opt=N] int i2 end row
    -- @tparam[opt=M] int j2 end col
    -- @see parse_range
    -- @return i1, j1, i2, j2
    function array2d.default_range (t,i1,j1,i2,j2)
        if (type(i1) == 'string') and not (j1 or i2 or j2) then
            i1, j1, i2, j2 = array2d.parse_range(i1)
        end
        local nr, nc = array2d.size(t)
        i1 = norm_value(i1 or 1, nr)
        j1 = norm_value(j1 or 1, nc)
        i2 = norm_value(i2 or nr, nr)
        j2 = norm_value(j2 or nc, nc)
        return i1,j1,i2,j2
    end
    default_range = array2d.default_range
end

--- get a slice of a 2D array. Note that if the specified range has
-- a 1D result, the rank of the result will be 1.
-- @array2d t a 2D array
-- @tparam[opt=1] int|string i1 start row or spreadsheet range passed to `parse_range`
-- @tparam[opt=1] int j1 start col
-- @tparam[opt=N] int i2 end row
-- @tparam[opt=M] int j2 end col
-- @see parse_range
-- @return an array, 2D in general but 1D in special cases.
function array2d.slice (t,i1,j1,i2,j2)
    assert_arg(1,t,'table')
    i1,j1,i2,j2 = default_range(t,i1,j1,i2,j2)
    local res = {}
    for i = i1,i2 do
        local val
        local row = t[i]
        if j1 == j2 then
            val = row[j1]
        else
            val = {}
            for j = j1,j2 do
                val[#val+1] = row[j]
            end
        end
        res[#res+1] = val
    end
    if i1 == i2 then res = res[1] end
    return obj(t,res)
end

--- set a specified range of an array to a value.
-- @array2d t a 2D array
-- @param value the value (may be a function, called as `val(i,j)`)
-- @tparam[opt=1] int|string i1 start row or spreadsheet range passed to `parse_range`
-- @tparam[opt=1] int j1 start col
-- @tparam[opt=N] int i2 end row
-- @tparam[opt=M] int j2 end col
-- @see parse_range
-- @see tablex.set
function array2d.set (t,value,i1,j1,i2,j2)
    i1,j1,i2,j2 = default_range(t,i1,j1,i2,j2)
    local i = i1
    if types.is_callable(value) then
        local old_f = value
        value = function(j)
            return old_f(i,j)
        end
    end
    while i <= i2 do
        tset(t[i],value,j1,j2)
        i = i + 1
    end
end

--- write a 2D array to a file.
-- @array2d t a 2D array
-- @param f a file object (default stdout)
-- @string fmt a format string (default is just to use tostring)
-- @tparam[opt=1] int|string i1 start row or spreadsheet range passed to `parse_range`
-- @tparam[opt=1] int j1 start col
-- @tparam[opt=N] int i2 end row
-- @tparam[opt=M] int j2 end col
-- @see parse_range
function array2d.write (t,f,fmt,i1,j1,i2,j2)
    assert_arg(1,t,'table')
    f = f or stdout
    local rowop
    if fmt then
        rowop = function(row,j) fprintf(f,fmt,row[j]) end
    else
        rowop = function(row,j) f:write(tostring(row[j]),' ') end
    end
    local function newline()
        f:write '\n'
    end
    array2d.forall(t,rowop,newline,i1,j1,i2,j2)
end

--- perform an operation for all values in a 2D array.
-- @array2d t 2D array
-- @func row_op function to call on each value; `row_op(row,j)`
-- @func end_row_op function to call at end of each row; `end_row_op(i)`
-- @tparam[opt=1] int|string i1 start row or spreadsheet range passed to `parse_range`
-- @tparam[opt=1] int j1 start col
-- @tparam[opt=N] int i2 end row
-- @tparam[opt=M] int j2 end col
-- @see parse_range
function array2d.forall (t,row_op,end_row_op,i1,j1,i2,j2)
    assert_arg(1,t,'table')
    i1,j1,i2,j2 = default_range(t,i1,j1,i2,j2)
    for i = i1,i2 do
        local row = t[i]
        for j = j1,j2 do
            row_op(row,j)
        end
        if end_row_op then end_row_op(i) end
    end
end

---- move a block from the destination to the source.
-- @array2d dest a 2D array
-- @int di start row in dest
-- @int dj start col in dest
-- @array2d src a 2D array
-- @tparam[opt=1] int|string i1 start row or spreadsheet range passed to `parse_range`
-- @tparam[opt=1] int j1 start col
-- @tparam[opt=N] int i2 end row
-- @tparam[opt=M] int j2 end col
-- @see parse_range
function array2d.move (dest,di,dj,src,i1,j1,i2,j2)
    assert_arg(1,dest,'table')
    assert_arg(4,src,'table')
    i1,j1,i2,j2 = default_range(src,i1,j1,i2,j2)
    local nr,nc = array2d.size(dest)
    i2, j2 = min(nr,i2), min(nc,j2)
    --i1, j1 = max(1,i1), max(1,j1)
    dj = dj - 1
    for i = i1,i2 do
        local drow, srow = dest[i+di-1], src[i]
        for j = j1,j2 do
            drow[j+dj] = srow[j]
        end
    end
end

--- iterate over all elements in a 2D array, with optional indices.
-- @array2d a 2D array
-- @bool indices with indices (default false)
-- @tparam[opt=1] int|string i1 start row or spreadsheet range passed to `parse_range`
-- @tparam[opt=1] int j1 start col
-- @tparam[opt=N] int i2 end row
-- @tparam[opt=M] int j2 end col
-- @see parse_range
-- @return either `value` or `i,j,value` depending on the value of `indices`
function array2d.iter(a,indices,i1,j1,i2,j2)
    assert_arg(1,a,'table')
    i1,j1,i2,j2 = default_range(a,i1,j1,i2,j2)
    local i,j = i1,j1-1
    local row = a[i]
    return function()
        j = j + 1
        if j > j2 then
            j = j1
            i = i + 1
            row = a[i]
            if i > i2 then
                return nil
            end
        end
        if indices then
            return i,j,row[j]
        else
            return row[j]
        end
    end
end

--- iterate over all columns.
-- @array2d a a 2D array
-- @return column, column-index
function array2d.columns(a)
  assert_arg(1,a,'table')
  local n = #a[1]
  local i = 0
  return function()
      i = i + 1
      if i > n then return nil end
      return column(a,i), i
  end
end

--- iterate over all rows.
-- Returns a copy of the row, for read-only purposes directly iterating
-- is more performant; `ipairs(a)`
-- @array2d a a 2D array
-- @return row, row-index
function array2d.rows(a)
  assert_arg(1,a,'table')
  local n = #a
  local i = 0
  return function()
      i = i + 1
      if i > n then return nil end
      return array2d.row(a,i), i
  end
end

--- new array of specified dimensions
-- @int rows number of rows
-- @int cols number of cols
-- @param val initial value; if it's a function then use `val(i,j)`
-- @return new 2d array
function array2d.new(rows,cols,val)
    local res = {}
    local fun = types.is_callable(val)
    for i = 1,rows do
        local row = {}
        if fun then
            for j = 1,cols do row[j] = val(i,j) end
        else
            for j = 1,cols do row[j] = val end
        end
        res[i] = row
    end
    return res
end

return array2d

end,

["pl.class"] = function()
--------------------
-- Module: 'pl.class'
--------------------
--- Provides a reuseable and convenient framework for creating classes in Lua.
-- Two possible notations:
--
--    B = class(A)
--    class.B(A)
--
-- The latter form creates a named class within the current environment. Note
-- that this implicitly brings in `pl.utils` as a dependency.
--
-- See the Guide for further @{01-introduction.md.Simplifying_Object_Oriented_Programming_in_Lua|discussion}
-- @module pl.class

local error, getmetatable, io, pairs, rawget, rawset, setmetatable, tostring, type =
    _G.error, _G.getmetatable, _G.io, _G.pairs, _G.rawget, _G.rawset, _G.setmetatable, _G.tostring, _G.type
local compat

-- this trickery is necessary to prevent the inheritance of 'super' and
-- the resulting recursive call problems.
local function call_ctor (c,obj,...)
    local init = rawget(c,'_init')
    local parent_with_init = rawget(c,'_parent_with_init')

    if parent_with_init then
        if not init then -- inheriting an init
            init = rawget(parent_with_init, '_init')
            parent_with_init = rawget(parent_with_init, '_parent_with_init')
        end
        if parent_with_init then -- super() points to one above whereever _init came from
            rawset(obj,'super',function(obj,...)
                call_ctor(parent_with_init,obj,...)
            end)
        end
    else
        -- Without this, calling super() where none exists will sometimes loop and stack overflow
        rawset(obj,'super',nil)
    end

    local res = init(obj,...)
    if parent_with_init then -- If this execution of call_ctor set a super, unset it
        rawset(obj,'super',nil)
    end

    return res
end

--- initializes an __instance__ upon creation.
-- @function class:_init
-- @param ... parameters passed to the constructor
-- @usage local Cat = class()
-- function Cat:_init(name)
--   --self:super(name)   -- call the ancestor initializer if needed
--   self.name = name
-- end
--
-- local pussycat = Cat("pussycat")
-- print(pussycat.name)  --> pussycat

--- checks whether an __instance__ is derived from some class.
-- Works the other way around as `class_of`. It has two ways of using;
-- 1) call with a class to check against, 2) call without params.
-- @function instance:is_a
-- @param some_class class to check against, or `nil` to return the class
-- @return `true` if `instance` is derived from `some_class`, or if `some_class == nil` then
-- it returns the class table of the instance
-- @usage local pussycat = Lion()  -- assuming Lion derives from Cat
-- if pussycat:is_a(Cat) then
--   -- it's true, it is a Lion, but also a Cat
-- end
--
-- if pussycat:is_a() == Lion then
--   -- It's true
-- end
local function is_a(self,klass)
    if klass == nil then
        -- no class provided, so return the class this instance is derived from
        return getmetatable(self)
    end
    local m = getmetatable(self)
    if not m then return false end --*can't be an object!
    while m do
        if m == klass then return true end
        m = rawget(m,'_base')
    end
    return false
end

--- checks whether an __instance__ is derived from some class.
-- Works the other way around as `is_a`.
-- @function some_class:class_of
-- @param some_instance instance to check against
-- @return `true` if `some_instance` is derived from `some_class`
-- @usage local pussycat = Lion()  -- assuming Lion derives from Cat
-- if Cat:class_of(pussycat) then
--   -- it's true
-- end
local function class_of(klass,obj)
    if type(klass) ~= 'table' or not rawget(klass,'is_a') then return false end
    return klass.is_a(obj,klass)
end

--- cast an object to another class.
-- It is not clever (or safe!) so use carefully.
-- @param some_instance the object to be changed
-- @function some_class:cast
local function cast (klass, obj)
    return setmetatable(obj,klass)
end


local function _class_tostring (obj)
    local mt = obj._class
    local name = rawget(mt,'_name')
    setmetatable(obj,nil)
    local str = tostring(obj)
    setmetatable(obj,mt)
    if name then str = name ..str:gsub('table','') end
    return str
end

local function tupdate(td,ts,dont_override)
    for k,v in pairs(ts) do
        if not dont_override or td[k] == nil then
            td[k] = v
        end
    end
end

local function _class(base,c_arg,c)
    -- the class `c` will be the metatable for all its objects,
    -- and they will look up their methods in it.
    local mt = {}   -- a metatable for the class to support __call and _handler
    -- can define class by passing it a plain table of methods
    local plain = type(base) == 'table' and not getmetatable(base)
    if plain then
        c = base
        base = c._base
    else
        c = c or {}
    end

    if type(base) == 'table' then
        -- our new class is a shallow copy of the base class!
        -- but be careful not to wipe out any methods we have been given at this point!
        tupdate(c,base,plain)
        c._base = base
        -- inherit the 'not found' handler, if present
        if rawget(c,'_handler') then mt.__index = c._handler end
    elseif base ~= nil then
        error("must derive from a table type",3)
    end

    c.__index = c
    setmetatable(c,mt)
    if not plain then
        if base and rawget(base,'_init') then c._parent_with_init = base end -- For super and inherited init
        c._init = nil
    end

    if base and rawget(base,'_class_init') then
        base._class_init(c,c_arg)
    end

    -- expose a ctor which can be called by <classname>(<args>)
    mt.__call = function(class_tbl,...)
        local obj
        if rawget(c,'_create') then obj = c._create(...) end
        if not obj then obj = {} end
        setmetatable(obj,c)

        if rawget(c,'_init') or rawget(c,'_parent_with_init') then -- constructor exists
            local res = call_ctor(c,obj,...)
            if res then -- _if_ a ctor returns a value, it becomes the object...
                obj = res
                setmetatable(obj,c)
            end
        end

        if base and rawget(base,'_post_init') then
            base._post_init(obj)
        end

        return obj
    end
    -- Call Class.catch to set a handler for methods/properties not found in the class!
    c.catch = function(self, handler)
        if type(self) == "function" then
            -- called using . instead of :
            handler = self
        end
        c._handler = handler
        mt.__index = handler
    end
    c.is_a = is_a
    c.class_of = class_of
    c.cast = cast
    c._class = c

    if not rawget(c,'__tostring') then
        c.__tostring = _class_tostring
    end

    return c
end

--- create a new class, derived from a given base class.
-- Supporting two class creation syntaxes:
-- either `Name = class(base)` or `class.Name(base)`.
-- The first form returns the class directly and does not set its `_name`.
-- The second form creates a variable `Name` in the current environment set
-- to the class, and also sets `_name`.
-- @function class
-- @param base optional base class
-- @param c_arg optional parameter to class constructor
-- @param c optional table to be used as class
local class
class = setmetatable({},{
    __call = function(fun,...)
        return _class(...)
    end,
    __index = function(tbl,key)
        if key == 'class' then
            io.stderr:write('require("pl.class").class is deprecated. Use require("pl.class")\n')
            return class
        end
        compat = compat or require 'pl.compat'
        local env = compat.getfenv(2)
        return function(...)
            local c = _class(...)
            c._name = key
            rawset(env,key,c)
            return c
        end
    end
})

class.properties = class()

function class.properties._class_init(klass)
    klass.__index = function(t,key)
        -- normal class lookup!
        local v = klass[key]
        if v then return v end
        -- is it a getter?
        v = rawget(klass,'get_'..key)
        if v then
            return v(t)
        end
        -- is it a field?
        return rawget(t,'_'..key)
    end
    klass.__newindex = function (t,key,value)
        -- if there's a setter, use that, otherwise directly set table
        local p = 'set_'..key
        local setter = klass[p]
        if setter then
            setter(t,value)
        else
            rawset(t,key,value)
        end
    end
end


return class


end,

["pl.compat"] = function()
--------------------
-- Module: 'pl.compat'
--------------------
----------------
--- Lua 5.1/5.2/5.3 compatibility.
-- Injects `table.pack`, `table.unpack`, and `package.searchpath` in the global
-- environment, to make sure they are available for Lua 5.1 and LuaJIT.
--
-- All other functions are exported as usual in the returned module table.
--
-- NOTE: everything in this module is also available in `pl.utils`.
-- @module pl.compat
local compat = {}

--- boolean flag this is Lua 5.1 (or LuaJIT).
-- @field lua51
compat.lua51 = _VERSION == 'Lua 5.1'

--- boolean flag this is LuaJIT.
-- @field jit
compat.jit = (tostring(assert):match('builtin') ~= nil)

--- boolean flag this is LuaJIT with 5.2 compatibility compiled in.
-- @field jit52
if compat.jit then
    -- 'goto' is a keyword when 52 compatibility is enabled in LuaJit
    compat.jit52 = not loadstring("local goto = 1")
end

--- the directory separator character for the current platform.
-- @field dir_separator
compat.dir_separator = _G.package.config:sub(1,1)

--- boolean flag this is a Windows platform.
-- @field is_windows
compat.is_windows = compat.dir_separator == '\\'

--- execute a shell command, in a compatible and platform independent way.
-- This is a compatibility function that returns the same for Lua 5.1 and
-- Lua 5.2+.
--
-- NOTE: Windows systems can use signed 32bit integer exitcodes. Posix systems
-- only use exitcodes 0-255, anything else is undefined.
--
-- NOTE2: In Lua 5.2 and 5.3 a Windows exitcode of -1 would not properly be
-- returned, this function will return it properly for all versions.
-- @param cmd a shell command
-- @return true if successful
-- @return actual return code
function compat.execute(cmd)
    local res1,res2,res3 = os.execute(cmd)
    if res2 == "No error" and res3 == 0 and compat.is_windows then
      -- os.execute bug in Lua 5.2/5.3 not reporting -1 properly on Windows
      -- this was fixed in 5.4
      res3 = -1
    end
    if compat.lua51 and not compat.jit52 then
        if compat.is_windows then
            return res1==0,res1
        else
            res1 = res1 > 255 and res1 / 256 or res1
            return res1==0,res1
        end
    else
        if compat.is_windows then
            return res3==0,res3
        else
            return not not res1,res3
        end
    end
end

----------------
-- Load Lua code as a text or binary chunk (in a Lua 5.2 compatible way).
-- @param ld code string or loader
-- @param[opt] source name of chunk for errors
-- @param[opt] mode 'b', 't' or 'bt'
-- @param[opt] env environment to load the chunk in
-- @function compat.load

---------------
-- Get environment of a function (in a Lua 5.1 compatible way).
-- Not 100% compatible, so with Lua 5.2 it may return nil for a function with no
-- global references!
-- Based on code by [Sergey Rozhenko](http://lua-users.org/lists/lua-l/2010-06/msg00313.html)
-- @param f a function or a call stack reference
-- @function compat.getfenv

---------------
-- Set environment of a function (in a Lua 5.1 compatible way).
-- @param f a function or a call stack reference
-- @param env a table that becomes the new environment of `f`
-- @function compat.setfenv

if compat.lua51 then -- define Lua 5.2 style load()
    if not compat.jit then -- but LuaJIT's load _is_ compatible
        local lua51_load = load
        function compat.load(str,src,mode,env)
            local chunk,err
            if type(str) == 'string' then
                if str:byte(1) == 27 and not (mode or 'bt'):find 'b' then
                    return nil,"attempt to load a binary chunk"
                end
                chunk,err = loadstring(str,src)
            else
                chunk,err = lua51_load(str,src)
            end
            if chunk and env then setfenv(chunk,env) end
            return chunk,err
        end
    else
        compat.load = load
    end
    compat.setfenv, compat.getfenv = setfenv, getfenv
else
    compat.load = load
    -- setfenv/getfenv replacements for Lua 5.2
    -- by Sergey Rozhenko
    -- http://lua-users.org/lists/lua-l/2010-06/msg00313.html
    -- Roberto Ierusalimschy notes that it is possible for getfenv to return nil
    -- in the case of a function with no globals:
    -- http://lua-users.org/lists/lua-l/2010-06/msg00315.html
    function compat.setfenv(f, t)
        f = (type(f) == 'function' and f or debug.getinfo(f + 1, 'f').func)
        local name
        local up = 0
        repeat
            up = up + 1
            name = debug.getupvalue(f, up)
        until name == '_ENV' or name == nil
        if name then
            debug.upvaluejoin(f, up, function() return name end, 1) -- use unique upvalue
            debug.setupvalue(f, up, t)
        end
        if f ~= 0 then return f end
    end

    function compat.getfenv(f)
        local f = f or 0
        f = (type(f) == 'function' and f or debug.getinfo(f + 1, 'f').func)
        local name, val
        local up = 0
        repeat
            up = up + 1
            name, val = debug.getupvalue(f, up)
        until name == '_ENV' or name == nil
        return val
    end
end


--- Global exported functions (for Lua 5.1 & LuaJIT)
-- @section lua52

--- pack an argument list into a table.
-- @param ... any arguments
-- @return a table with field n set to the length
-- @function table.pack
if not table.pack then
    function table.pack (...)       -- luacheck: ignore
        return {n=select('#',...); ...}
    end
end

--- unpack a table and return the elements.
--
-- NOTE: this version does NOT honor the n field, and hence it is not nil-safe.
-- See `utils.unpack` for a version that is nil-safe.
-- @param t table to unpack
-- @param[opt] i index from which to start unpacking, defaults to 1
-- @param[opt] j index of the last element to unpack, defaults to #t
-- @return multiple return values from the table
-- @function table.unpack
-- @see utils.unpack
if not table.unpack then
    table.unpack = unpack           -- luacheck: ignore
end

--- return the full path where a file name would be matched.
-- This function was introduced in Lua 5.2, so this compatibility version
-- will be injected in Lua 5.1 engines.
-- @string name file name, possibly dotted
-- @string path a path-template in the same form as package.path or package.cpath
-- @string[opt] sep template separate character to be replaced by path separator. Default: "."
-- @string[opt] rep the path separator to use, defaults to system separator. Default; "/" on Unixes, "\" on Windows.
-- @see path.package_path
-- @function package.searchpath
-- @return on success: path of the file
-- @return on failure: nil, error string listing paths tried
if not package.searchpath then
    function package.searchpath (name,path,sep,rep)    -- luacheck: ignore
        if type(name) ~= "string" then
            error(("bad argument #1 to 'searchpath' (string expected, got %s)"):format(type(path)), 2)
        end
        if type(path) ~= "string" then
            error(("bad argument #2 to 'searchpath' (string expected, got %s)"):format(type(path)), 2)
        end
        if sep ~= nil and type(sep) ~= "string" then
            error(("bad argument #3 to 'searchpath' (string expected, got %s)"):format(type(path)), 2)
        end
        if rep ~= nil and type(rep) ~= "string" then
            error(("bad argument #4 to 'searchpath' (string expected, got %s)"):format(type(path)), 2)
        end
        sep = sep or "."
        rep = rep or compat.dir_separator
        do
          local s, e = name:find(sep, nil, true)
          while s do
            name = name:sub(1, s-1) .. rep .. name:sub(e+1, -1)
            s, e = name:find(sep, s + #rep + 1, true)
          end
        end
        local tried = {}
        for m in path:gmatch('[^;]+') do
            local nm = m:gsub('?', name)
            tried[#tried+1] = nm
            local f = io.open(nm,'r')
            if f then f:close(); return nm end
        end
        return nil, "\tno file '" .. table.concat(tried, "'\n\tno file '") .. "'"
    end
end

--- Global exported functions (for Lua < 5.4)
-- @section lua54

--- raise a warning message.
-- This functions mimics the `warn` function added in Lua 5.4.
-- @function warn
-- @param ... any arguments
if not warn then  -- luacheck: ignore
    local enabled = false
    local function warn(arg1, ...)  -- luacheck: ignore
        if type(arg1) == "string" and arg1:sub(1, 1) == "@" then
            -- control message
            if arg1 == "@on" then
                enabled = true
                return
            end
            if arg1 == "@off" then
                enabled = false
                return
            end
            return -- ignore unknown control messages
        end
        if enabled then
          io.stderr:write("Lua warning: ", arg1, ...)
          io.stderr:write("\n")
        end
    end
    -- use rawset to bypass OpenResty's protection of global scope
    rawset(_G, "warn", warn)
end

return compat

end,

["pl.comprehension"] = function()
--------------------
-- Module: 'pl.comprehension'
--------------------
--- List comprehensions implemented in Lua.
--
-- See the [wiki page](http://lua-users.org/wiki/ListComprehensions)
--
--    local C= require 'pl.comprehension' . new()
--
--    C ('x for x=1,10') ()
--    ==> {1,2,3,4,5,6,7,8,9,10}
--    C 'x^2 for x=1,4' ()
--    ==> {1,4,9,16}
--    C '{x,x^2} for x=1,4' ()
--    ==> {{1,1},{2,4},{3,9},{4,16}}
--    C '2*x for x' {1,2,3}
--    ==> {2,4,6}
--    dbl = C '2*x for x'
--    dbl {10,20,30}
--    ==> {20,40,60}
--    C 'x for x if x % 2 == 0' {1,2,3,4,5}
--    ==> {2,4}
--    C '{x,y} for x = 1,2 for y = 1,2' ()
--    ==> {{1,1},{1,2},{2,1},{2,2}}
--    C '{x,y} for x for y' ({1,2},{10,20})
--    ==> {{1,10},{1,20},{2,10},{2,20}}
--    assert(C 'sum(x^2 for x)' {2,3,4} == 2^2+3^2+4^2)
--
-- (c) 2008 David Manura. Licensed under the same terms as Lua (MIT license).
--
-- Dependencies: `pl.utils`, `pl.luabalanced`
--
-- See @{07-functional.md.List_Comprehensions|the Guide}
-- @module pl.comprehension

local utils = require 'pl.utils'

local status,lb = pcall(require, "pl.luabalanced")
if not status then
    lb = require 'luabalanced'
end

local math_max = math.max
local table_concat = table.concat

-- fold operations
-- http://en.wikipedia.org/wiki/Fold_(higher-order_function)
local ops = {
  list = {init=' {} ', accum=' __result[#__result+1] = (%s) '},
  table = {init=' {} ', accum=' local __k, __v = %s __result[__k] = __v '},
  sum = {init=' 0 ', accum=' __result = __result + (%s) '},
  min = {init=' nil ', accum=' local __tmp = %s ' ..
                             ' if __result then if __tmp < __result then ' ..
                             '__result = __tmp end else __result = __tmp end '},
  max = {init=' nil ', accum=' local __tmp = %s ' ..
                             ' if __result then if __tmp > __result then ' ..
                             '__result = __tmp end else __result = __tmp end '},
}


-- Parses comprehension string expr.
-- Returns output expression list <out> string, array of for types
-- ('=', 'in' or nil) <fortypes>, array of input variable name
-- strings <invarlists>, array of input variable value strings
-- <invallists>, array of predicate expression strings <preds>,
-- operation name string <opname>, and number of placeholder
-- parameters <max_param>.
--
-- The is equivalent to the mathematical set-builder notation:
--
--   <opname> { <out> | <invarlist> in <invallist> , <preds> }
--
-- @usage   "x^2 for x"                 -- array values
-- @usage  "x^2 for x=1,10,2"          -- numeric for
-- @usage  "k^v for k,v in pairs(_1)"  -- iterator for
-- @usage  "(x+y)^2 for x for y if x > y"  -- nested
--
local function parse_comprehension(expr)
  local pos = 1

  -- extract opname (if exists)
  local opname
  local tok, post = expr:match('^%s*([%a_][%w_]*)%s*%(()', pos)
  local pose = #expr + 1
  if tok then
    local tok2, posb = lb.match_bracketed(expr, post-1)
    assert(tok2, 'syntax error')
    if expr:match('^%s*$', posb) then
      opname = tok
      pose = posb - 1
      pos = post
    end
  end
  opname = opname or "list"

  -- extract out expression list
  local out; out, pos = lb.match_explist(expr, pos)
  assert(out, "syntax error: missing expression list")
  out = table_concat(out, ', ')

  -- extract "for" clauses
  local fortypes = {}
  local invarlists = {}
  local invallists = {}
  while 1 do
    local post = expr:match('^%s*for%s+()', pos)
    if not post then break end
    pos = post

    -- extract input vars
    local iv; iv, pos = lb.match_namelist(expr, pos)
    assert(#iv > 0, 'syntax error: zero variables')
    for _,ident in ipairs(iv) do
      assert(not ident:match'^__',
             "identifier " .. ident .. " may not contain __ prefix")
    end
    invarlists[#invarlists+1] = iv

    -- extract '=' or 'in' (optional)
    local fortype, post = expr:match('^(=)%s*()', pos)
    if not fortype then fortype, post = expr:match('^(in)%s+()', pos) end
    if fortype then
      pos = post
      -- extract input value range
      local il; il, pos = lb.match_explist(expr, pos)
      assert(#il > 0, 'syntax error: zero expressions')
      assert(fortype ~= '=' or #il == 2 or #il == 3,
             'syntax error: numeric for requires 2 or three expressions')
      fortypes[#invarlists] = fortype
      invallists[#invarlists] = il
    else
      fortypes[#invarlists] = false
      invallists[#invarlists] = false
    end
  end
  assert(#invarlists > 0, 'syntax error: missing "for" clause')

  -- extract "if" clauses
  local preds = {}
  while 1 do
    local post = expr:match('^%s*if%s+()', pos)
    if not post then break end
    pos = post
    local pred; pred, pos = lb.match_expression(expr, pos)
    assert(pred, 'syntax error: predicated expression not found')
    preds[#preds+1] = pred
  end

  -- extract number of parameter variables (name matching "_%d+")
  local stmp = ''; lb.gsub(expr, function(u, sin)  -- strip comments/strings
    if u == 'e' then stmp = stmp .. ' ' .. sin .. ' ' end
  end)
  local max_param = 0; stmp:gsub('[%a_][%w_]*', function(s)
    local s = s:match('^_(%d+)$')
    if s then max_param = math_max(max_param, tonumber(s)) end
  end)

  if pos ~= pose then
    assert(false, "syntax error: unrecognized " .. expr:sub(pos))
  end

  --DEBUG:
  --print('----\n', string.format("%q", expr), string.format("%q", out), opname)
  --for k,v in ipairs(invarlists) do print(k,v, invallists[k]) end
  --for k,v in ipairs(preds) do print(k,v) end

  return out, fortypes, invarlists, invallists, preds, opname, max_param
end


-- Create Lua code string representing comprehension.
-- Arguments are in the form returned by parse_comprehension.
local function code_comprehension(
    out, fortypes, invarlists, invallists, preds, opname, max_param
)
  local op = assert(ops[opname])
  local code = op.accum:gsub('%%s',  out)

  for i=#preds,1,-1 do local pred = preds[i]
    code = ' if ' .. pred .. ' then ' .. code .. ' end '
  end
  for i=#invarlists,1,-1 do
    if not fortypes[i] then
      local arrayname = '__in' .. i
      local idx = '__idx' .. i
      code =
        ' for ' .. idx .. ' = 1, #' .. arrayname .. ' do ' ..
        ' local ' .. invarlists[i][1] .. ' = ' .. arrayname .. '['..idx..'] ' ..
        code .. ' end '
    else
      code =
        ' for ' ..
        table_concat(invarlists[i], ', ') ..
        ' ' .. fortypes[i] .. ' ' ..
        table_concat(invallists[i], ', ') ..
        ' do ' .. code .. ' end '
    end
  end
  code = ' local __result = ( ' .. op.init .. ' ) ' .. code
  return code
end


-- Convert code string represented by code_comprehension
-- into Lua function.  Also must pass ninputs = #invarlists,
-- max_param, and invallists (from parse_comprehension).
-- Uses environment env.
local function wrap_comprehension(code, ninputs, max_param, invallists, env)
  assert(ninputs > 0)
  local ts = {}
  for i=1,max_param do
    ts[#ts+1] = '_' .. i
  end
  for i=1,ninputs do
    if not invallists[i] then
      local name = '__in' .. i
      ts[#ts+1] = name
    end
  end
  if #ts > 0 then
    code = ' local ' .. table_concat(ts, ', ') .. ' = ... ' .. code
  end
  code = code .. ' return __result '
  --print('DEBUG:', code)
  local f, err = utils.load(code,'tmp','t',env)
  if not f then assert(false, err .. ' with generated code ' .. code) end
  return f
end


-- Build Lua function from comprehension string.
-- Uses environment env.
local function build_comprehension(expr, env)
  local out, fortypes, invarlists, invallists, preds, opname, max_param
    = parse_comprehension(expr)
  local code = code_comprehension(
    out, fortypes, invarlists, invallists, preds, opname, max_param)
  local f = wrap_comprehension(code, #invarlists, max_param, invallists, env)
  return f
end


-- Creates new comprehension cache.
-- Any list comprehension function created are set to the environment
-- env (defaults to caller of new).
local function new(env)
  -- Note: using a single global comprehension cache would have had
  -- security implications (e.g. retrieving cached functions created
  -- in other environments).
  -- The cache lookup function could have instead been written to retrieve
  -- the caller's environment, lookup up the cache private to that
  -- environment, and then looked up the function in that cache.
  -- That would avoid the need for this <new> call to
  -- explicitly manage caches; however, that might also have an undue
  -- performance penalty.

  if not env then
    env = utils.getfenv(2)
  end

  local mt = {}
  local cache = setmetatable({}, mt)

  -- Index operator builds, caches, and returns Lua function
  -- corresponding to comprehension expression string.
  --
  -- Example: f = comprehension['x^2 for x']
  --
  function mt:__index(expr)
    local f = build_comprehension(expr, env)
    self[expr] = f  -- cache
    return f
  end

  -- Convenience syntax.
  -- Allows comprehension 'x^2 for x' instead of comprehension['x^2 for x'].
  mt.__call = mt.__index

  cache.new = new

  return cache
end


local comprehension = {}
comprehension.new = new

return comprehension

end,

["pl.config"] = function()
--------------------
-- Module: 'pl.config'
--------------------
--- Reads configuration files into a Lua table.
--  Understands INI files, classic Unix config files, and simple
-- delimited columns of values. See @{06-data.md.Reading_Configuration_Files|the Guide}
--
--    # test.config
--    # Read timeout in seconds
--    read.timeout=10
--    # Write timeout in seconds
--    write.timeout=5
--    #acceptable ports
--    ports = 1002,1003,1004
--
--    -- readconfig.lua
--    local config = require 'config'
--    local t = config.read 'test.config'
--    print(pretty.write(t))
--
--    ### output #####
--    {
--      ports = {
--        1002,
--        1003,
--        1004
--      },
--      write_timeout = 5,
--      read_timeout = 10
--    }
--
-- @module pl.config

local type,tonumber,ipairs,io, table = _G.type,_G.tonumber,_G.ipairs,_G.io,_G.table

local function split(s,re)
    local res = {}
    local t_insert = table.insert
    re = '[^'..re..']+'
    for k in s:gmatch(re) do t_insert(res,k) end
    return res
end

local function strip(s)
    return s:gsub('^%s+',''):gsub('%s+$','')
end

local function strip_quotes (s)
    return s:gsub("['\"](.*)['\"]",'%1')
end

local config = {}

--- like io.lines(), but allows for lines to be continued with '\'.
-- @param file a file-like object (anything where read() returns the next line) or a filename.
-- Defaults to stardard input.
-- @return an iterator over the lines, or nil
-- @return error 'not a file-like object' or 'file is nil'
function config.lines(file)
    local f,openf,err
    local line = ''
    if type(file) == 'string' then
        f,err = io.open(file,'r')
        if not f then return nil,err end
        openf = true
    else
        f = file or io.stdin
        if not file.read then return nil, 'not a file-like object' end
    end
    if not f then return nil, 'file is nil' end
    return function()
        local l = f:read()
        while l do
            -- only for non-blank lines that don't begin with either ';' or '#'
            if l:match '%S' and not l:match '^%s*[;#]' then
                -- does the line end with '\'?
                local i = l:find '\\%s*$'
                if i then -- if so,
                    line = line..l:sub(1,i-1)
                elseif line == '' then
                    return l
                else
                    l = line..l
                    line = ''
                    return l
                end
            end
            l = f:read()
        end
        if openf then f:close() end
    end
end

--- read a configuration file into a table
-- @param file either a file-like object or a string, which must be a filename
-- @tab[opt] cnfg a configuration table that may contain these fields:
--
--  * `smart`  try to deduce what kind of config file we have (default false)
--  * `variabilize` make names into valid Lua identifiers (default true)
--  * `convert_numbers` try to convert values into numbers (default true)
--  * `trim_space` ensure that there is no starting or trailing whitespace with values (default true)
--  * `trim_quotes` remove quotes from strings (default false)
--  * `list_delim` delimiter to use when separating columns (default ',')
--  * `keysep` separator between key and value pairs (default '=')
--
-- @return a table containing items, or `nil`
-- @return error message (same as @{config.lines}
function config.read(file,cnfg)
    local auto

    local iter,err = config.lines(file)
    if not iter then return nil,err end
    local line = iter()
    cnfg = cnfg or {}
    if cnfg.smart then
        auto = true
        if line:match '^[^=]+=' then
            cnfg.keysep = '='
        elseif line:match '^[^:]+:' then
            cnfg.keysep = ':'
            cnfg.list_delim = ':'
        elseif line:match '^%S+%s+' then
            cnfg.keysep = ' '
            -- more than two columns assume that it's a space-delimited list
            -- cf /etc/fstab with /etc/ssh/ssh_config
            if line:match '^%S+%s+%S+%s+%S+' then
                cnfg.list_delim = ' '
            end
            cnfg.variabilize = false
        end
    end


    local function check_cnfg (var,def)
        local val = cnfg[var]
        if val == nil then return def else return val end
    end

    local initial_digits = '^[%d%+%-]'
    local t = {}
    local top_t = t
    local variabilize = check_cnfg ('variabilize',true)
    local list_delim = check_cnfg('list_delim',',')
    local convert_numbers = check_cnfg('convert_numbers',true)
    local convert_boolean = check_cnfg('convert_boolean',false)
    local trim_space = check_cnfg('trim_space',true)
    local trim_quotes = check_cnfg('trim_quotes',false)
    local ignore_assign = check_cnfg('ignore_assign',false)
    local keysep = check_cnfg('keysep','=')
    local keypat = keysep == ' ' and '%s+' or '%s*'..keysep..'%s*'
    if list_delim == ' ' then list_delim = '%s+' end

    local function process_name(key)
        if variabilize then
            key = key:gsub('[^%w]','_')
        end
        return key
    end

    local function process_value(value)
        if list_delim and value:find(list_delim) then
            value = split(value,list_delim)
            for i,v in ipairs(value) do
                value[i] = process_value(v)
            end
        elseif convert_numbers and value:find(initial_digits) then
            local val = tonumber(value)
            if not val and value:match ' kB$' then
                value = value:gsub(' kB','')
                val = tonumber(value)
            end
            if val then value = val end
        elseif convert_boolean and value == 'true' then
           return true
        elseif convert_boolean and value == 'false' then
           return false
        end
        if type(value) == 'string' then
           if trim_space then value = strip(value) end
           if not trim_quotes and auto and value:match '^"' then
                trim_quotes = true
            end
           if trim_quotes then value = strip_quotes(value) end
        end
        return value
    end

    while line do
        if line:find('^%[') then -- section!
            local section = process_name(line:match('%[([^%]]+)%]'))
            t = top_t
            t[section] = {}
            t = t[section]
        else
            line = line:gsub('^%s*','')
            local i1,i2 = line:find(keypat)
            if i1 and not ignore_assign then -- key,value assignment
                local key = process_name(line:sub(1,i1-1))
                local value = process_value(line:sub(i2+1))
                t[key] = value
            else -- a plain list of values...
                t[#t+1] = process_value(line)
            end
        end
        line = iter()
    end
    return top_t
end

return config

end,

["pl.data"] = function()
--------------------
-- Module: 'pl.data'
--------------------
--- Reading and querying simple tabular data.
--
--    data.read 'test.txt'
--    ==> {{10,20},{2,5},{40,50},fieldnames={'x','y'},delim=','}
--
-- Provides a way of creating basic SQL-like queries.
--
--    require 'pl'
--    local d = data.read('xyz.txt')
--    local q = d:select('x,y,z where x > 3 and z < 2 sort by y')
--    for x,y,z in q do
--        print(x,y,z)
--    end
--
-- See @{06-data.md.Reading_Columnar_Data|the Guide}
--
-- Dependencies: `pl.utils`, `pl.array2d` (fallback methods)
-- @module pl.data

local utils = require 'pl.utils'
local _DEBUG = rawget(_G,'_DEBUG')

local patterns,function_arg,usplit,array_tostring = utils.patterns,utils.function_arg,utils.split,utils.array_tostring
local append,concat = table.insert,table.concat
local gsub = string.gsub
local io = io
local _G,print,type,tonumber,ipairs,setmetatable = _G,print,type,tonumber,ipairs,setmetatable


local data = {}

local parse_select

local function rstrip(s)
    return (s:gsub('%s+$',''))
end

local function strip (s)
    return (rstrip(s):gsub('^%s*',''))
end

-- This gives `l` the standard List metatable,
-- pulling in the List module.
local function makelist(l)
    return setmetatable(l, require('pl.List'))
end

local function map(fun,t)
    local res = {}
    for i = 1,#t do
        res[i] = fun(t[i])
    end
    return res
end

local function split(line,delim,csv,n)
    local massage
    -- CSV fields may be double-quoted and may contain commas!
    if csv and line:match '"' then
        line = line:gsub('"([^"]+)"',function(str)
            local s,cnt = str:gsub(',','\001')
            if cnt > 0 then massage = true end
            return s
        end)
        if massage then
            massage = function(s) return (s:gsub('\001',',')) end
        end
    end
    local res = (usplit(line,delim,false,n))
    if csv then
        -- restore CSV commas-in-fields
        if massage then res = map(massage,res) end
        -- in CSV mode trailiing commas are significant!
        if line:match ',$' then append(res,'') end
    end
    return makelist(res)
end

local function find(t,v)
    for i = 1,#t do
        if v == t[i] then return i end
    end
end

local DataMT = {
    column_by_name = function(self,name)
        if type(name) == 'number' then
            name = '$'..name
        end
        local arr = {}
        for res in data.query(self,name) do
            append(arr,res)
        end
        return makelist(arr)
    end,

    copy_select = function(self,condn)
        condn = parse_select(condn,self)
        local iter = data.query(self,condn)
        local res = {}
        local row = makelist{iter()}
        while #row > 0 do
            append(res,row)
            row = makelist{iter()}
        end
        res.delim = self.delim
        return data.new(res,split(condn.fields,','))
    end,

    column_names = function(self)
        return self.fieldnames
    end,
}

local array2d

DataMT.__index = function(self,name)
    local f = DataMT[name]
    if f then return f end
    if not array2d then
        array2d = require 'pl.array2d'
    end
    return array2d[name]
end

--- return a particular column as a list of values (method).
-- @param name either name of column, or numerical index.
-- @function Data.column_by_name

--- return a query iterator on this data (method).
-- @string condn the query expression
-- @function Data.select
-- @see data.query

--- return a row iterator on this data (method).
-- @string condn the query expression
-- @function Data.select_row

--- return a new data object based on this query (method).
-- @string condn the query expression
-- @function Data.copy_select

--- return the field names of this data object (method).
-- @function Data.column_names

--- write out a row (method).
-- @param f file-like object
-- @function Data.write_row

--- write data out to file (method).
-- @param f file-like object
-- @function Data.write


-- [guessing delimiter] We check for comma, tab and spaces in that order.
-- [issue] any other delimiters to be checked?
local delims = {',', '\t', ' ', ';'}

local function guess_delim (line)
    if line=='' then return ' ' end
    for _,delim in ipairs(delims) do
        if line:find(delim) then
            return delim == ' ' and '%s+' or delim
        end
    end
    return ' '
end

-- [file parameter] If it's a string, we try open as a filename. If nil, then
-- either stdin or stdout depending on the mode. Otherwise, check if this is
-- a file-like object (implements read or write depending)
local function open_file (f,mode)
    local opened, err
    local reading = mode == 'r'
    if type(f) == 'string' then
        if f == 'stdin'  then
            f = io.stdin
        elseif f == 'stdout'  then
            f = io.stdout
        else
            f,err = io.open(f,mode)
            if not f then return nil,err end
            opened = true
        end
    end
    if f and ((reading and not f.read) or (not reading and not f.write)) then
        return nil, "not a file-like object"
    end
    return f,nil,opened
end

--- read a delimited file in a Lua table.
-- By default, attempts to treat first line as separated list of fieldnames.
-- @param file a filename or a file-like object
-- @tab cnfg parsing options
-- @string cnfg.delim a string pattern to split fields
-- @array cnfg.fieldnames (i.e. don't read from first line)
-- @bool cnfg.no_convert (default is to try conversion on first data line)
-- @tab cnfg.convert table of custom conversion functions with column keys
-- @int cnfg.numfields indices of columns known to be numbers
-- @bool cnfg.last_field_collect only split as many fields as fieldnames.
-- @int cnfg.thousands_dot thousands separator in Excel CSV is '.'
-- @bool cnfg.csv fields may be double-quoted and contain commas;
-- Also, empty fields are considered to be equivalent to zero.
-- @return `data` object, or `nil`
-- @return error message. May be a file error, 'not a file-like object'
-- or a conversion error
function data.read(file,cnfg)
    local count,line
    local D = {}
    if not cnfg then cnfg = {} end
    local f,err,opened = open_file(file,'r')
    if not f then return nil, err end
    local thousands_dot = cnfg.thousands_dot
    local csv = cnfg.csv
    if csv then cnfg.delim = ',' end

    -- note that using dot as the thousands separator (@thousands_dot)
    -- requires a special conversion function! For CSV, _empty fields_ are
    -- considered to default to numerial zeroes.
    local tonumber = tonumber
    local function try_number(x)
        if thousands_dot then x = x:gsub('%.(...)','%1') end
        if csv and x == '' then x = '0' end
        local v = tonumber(x)
        if v == nil then return nil,"not a number" end
        return v
    end

    count = 1
    line = f:read()
    if not line then return nil, "empty file" end

    -- first question: what is the delimiter?
    D.delim = cnfg.delim and cnfg.delim or guess_delim(line)
    local delim = D.delim

    local conversion
    local numfields = {}
    local function append_conversion (idx,conv)
        conversion = conversion or {}
        append(numfields,idx)
        append(conversion,conv)
    end
    if cnfg.numfields then
        for _,n in ipairs(cnfg.numfields) do append_conversion(n,try_number) end
    end

    -- some space-delimited data starts with a space.  This should not be a column,
    -- although it certainly would be for comma-separated, etc.
    local stripper
    if delim == '%s+' and line:find(delim) == 1 then
        stripper = function(s)  return s:gsub('^%s+','') end
        line = stripper(line)
    end
    -- first line will usually be field names. Unless fieldnames are specified,
    -- we check if it contains purely numerical values for the case of reading
    -- plain data files.
    if not cnfg.fieldnames then
        local fields,nums
        fields = split(line,delim,csv)
        if not cnfg.convert then
            nums = map(tonumber,fields)
            if #nums == #fields then -- they're ALL numbers!
                append(D,nums) -- add the first converted row
                -- and specify conversions for subsequent rows
                for i = 1,#nums do append_conversion(i,try_number) end
            else -- we'll try to check numbers just now..
                nums = nil
            end
        else -- [explicit column conversions] (any deduced number conversions will be added)
            for idx,conv in pairs(cnfg.convert) do append_conversion(idx,conv) end
        end
        if nums == nil then
            cnfg.fieldnames = fields
        end
        line = f:read()
        count = count + 1
        if stripper then line = stripper(line) end
    elseif type(cnfg.fieldnames) == 'string' then
        cnfg.fieldnames = split(cnfg.fieldnames,delim,csv)
    end
    local nfields
    -- at this point, the column headers have been read in. If the first
    -- row consisted of numbers, it has already been added to the dataset.
    if cnfg.fieldnames then
        D.fieldnames = cnfg.fieldnames
        -- [collecting end field] If @last_field_collect then we'll
        -- only split as many fields as there are fieldnames
        if cnfg.last_field_collect then
            nfields = #D.fieldnames
        end
        -- [implicit column conversion] unless @no_convert, we need the numerical field indices
        -- of the first data row. These can also be specified explicitly by @numfields.
        if not cnfg.no_convert then
            local fields = split(line,D.delim,csv,nfields)
            for i = 1,#fields do
                if not find(numfields,i) and try_number(fields[i]) then
                    append_conversion(i,try_number)
                end
            end
        end
    end
    -- keep going until finished
    while line do
        if not line:find ('^%s*$') then -- [blank lines] ignore them!
            if stripper then line = stripper(line) end
            local fields = split(line,delim,csv,nfields)
            if conversion then -- there were field conversions...
                for k = 1,#numfields do
                    local i,conv = numfields[k],conversion[k]
                    local val,err = conv(fields[i])
                    if val == nil then
                        return nil, err..": "..fields[i].." at line "..count
                    else
                        fields[i] = val
                    end
                end
            end
            append(D,fields)
        end
        line = f:read()
        count = count + 1
    end
    if opened then f:close() end
    if delim == '%s+' then D.delim = ' ' end
    if not D.fieldnames then D.fieldnames = {} end
    return data.new(D)
end

local function write_row (data,f,row,delim)
    data.temp = array_tostring(row,data.temp)
    f:write(concat(data.temp,delim),'\n')
end

function DataMT:write_row(f,row)
    write_row(self,f,row,self.delim)
end

--- write 2D data to a file.
-- Does not assume that the data has actually been
-- generated with `new` or `read`.
-- @param data 2D array
-- @param file filename or file-like object
-- @tparam[opt] {string} fieldnames list of fields (optional)
-- @string[opt='\t'] delim delimiter (default tab)
-- @return true or nil, error
function data.write (data,file,fieldnames,delim)
    local f,err,opened = open_file(file,'w')
    if not f then return nil, err end
    if not fieldnames then
        fieldnames = data.fieldnames
    end
    delim = delim or '\t'
    if fieldnames and #fieldnames > 0 then
        f:write(concat(fieldnames,delim),'\n')
    end
    for i = 1,#data do
        write_row(data,f,data[i],delim)
    end
    if opened then f:close() end
    return true
end


function DataMT:write(file)
    data.write(self,file,self.fieldnames,self.delim)
end

local function massage_fieldnames (fields,copy)
    -- fieldnames must be valid Lua identifiers; ignore any surrounding padding
    -- but keep the original fieldnames...
    for i = 1,#fields do
        local f = strip(fields[i])
        copy[i] = f
        fields[i] = f:gsub('%W','_')
    end
end

--- create a new dataset from a table of rows.
-- Can specify the fieldnames, else the table must have a field called
-- 'fieldnames', which is either a string of delimiter-separated names,
-- or a table of names. <br>
-- If the table does not have a field called 'delim', then an attempt will be
-- made to guess it from the fieldnames string, defaults otherwise to tab.
-- @param d the table.
-- @tparam[opt] {string} fieldnames optional fieldnames
-- @return the table.
function data.new (d,fieldnames)
    d.fieldnames = d.fieldnames or fieldnames or ''
    if not d.delim and type(d.fieldnames) == 'string' then
        d.delim = guess_delim(d.fieldnames)
        d.fieldnames = split(d.fieldnames,d.delim)
    end
    d.fieldnames = makelist(d.fieldnames)
    d.original_fieldnames = {}
    massage_fieldnames(d.fieldnames,d.original_fieldnames)
    setmetatable(d,DataMT)
    -- a query with just the fieldname will return a sequence
    -- of values, which seq.copy turns into a table.
    return d
end

local sorted_query = [[
return function (t)
    local i = 0
    local v
    local ls = {}
    for i,v in ipairs(t) do
        if CONDITION then
            ls[#ls+1] = v
        end
    end
    table.sort(ls,function(v1,v2)
        return SORT_EXPR
    end)
    local n = #ls
    return function()
        i = i + 1
        v = ls[i]
        if i > n then return end
        return FIELDLIST
    end
end
]]

-- question: is this optimized case actually worth the extra code?
local simple_query = [[
return function (t)
    local n = #t
    local i = 0
    local v
    return function()
        repeat
            i = i + 1
            v = t[i]
        until i > n or CONDITION
        if i > n then return end
        return FIELDLIST
    end
end
]]

local function is_string (s)
    return type(s) == 'string'
end

local field_error

local function fieldnames_as_string (data)
    return concat(data.fieldnames,',')
end

local function massage_fields(data,f)
    local idx
    if f:find '^%d+$' then
        idx = tonumber(f)
    else
        idx = find(data.fieldnames,f)
    end
    if idx then
        return 'v['..idx..']'
    else
        field_error = f..' not found in '..fieldnames_as_string(data)
        return f
    end
end


local function process_select (data,parms)
    --- preparing fields ----
    field_error = nil
    local fields = parms.fields
    local numfields = fields:find '%$'  or #data.fieldnames == 0
    if fields:find '^%s*%*%s*' then
        if not numfields then
            fields = fieldnames_as_string(data)
        else
            local ncol = #data[1]
            fields = {}
            for i = 1,ncol do append(fields,'$'..i) end
            fields = concat(fields,',')
        end
    end
    local idpat = patterns.IDEN
    if numfields then
        idpat = '%$(%d+)'
    else
        -- massage field names to replace non-identifier chars
        fields = rstrip(fields):gsub('[^,%w]','_')
    end
    local massage_fields = utils.bind1(massage_fields,data)
    local ret = gsub(fields,idpat,massage_fields)
    if field_error then return nil,field_error end
    parms.fields = fields
    parms.proc_fields = ret
    parms.where = parms.where or  'true'
    if is_string(parms.where) then
        parms.where = gsub(parms.where,idpat,massage_fields)
        field_error = nil
    end
    return true
end


parse_select = function(s,data)
    local endp
    local parms = {}
    local w1,w2 = s:find('where ')
    local s1,s2 = s:find('sort by ')
    if w1 then -- where clause!
        endp = (s1 or 0)-1
        parms.where = s:sub(w2+1,endp)
    end
    if s1 then -- sort by clause (must be last!)
        parms.sort_by = s:sub(s2+1)
    end
    endp = (w1 or s1 or 0)-1
    parms.fields = s:sub(1,endp)
    local status,err = process_select(data,parms)
    if not status then return nil,err
    else return parms end
end

--- create a query iterator from a select string.
-- Select string has this format: <br>
-- FIELDLIST [ where LUA-CONDN [ sort by FIELD] ]<br>
-- FIELDLIST is a comma-separated list of valid fields, or '*'. <br> <br>
-- The condition can also be a table, with fields 'fields' (comma-sep string or
-- table), 'sort_by' (string) and 'where' (Lua expression string or function)
-- @param data table produced by read
-- @param condn select string or table
-- @param context a list of tables to be searched when resolving functions
-- @param return_row if true, wrap the results in a row table
-- @return an iterator over the specified fields, or nil
-- @return an error message
function data.query(data,condn,context,return_row)
    local err
    if is_string(condn) then
        condn,err = parse_select(condn,data)
        if not condn then return nil,err end
    elseif type(condn) == 'table' then
        if type(condn.fields) == 'table' then
            condn.fields = concat(condn.fields,',')
        end
        if not condn.proc_fields then
            local status,err = process_select(data,condn)
            if not status then return nil,err end
        end
    else
        return nil, "condition must be a string or a table"
    end
    local query
    if condn.sort_by then -- use sorted_query
        query = sorted_query
    else
        query = simple_query
    end
    local fields = condn.proc_fields or condn.fields
    if return_row then
        fields = '{'..fields..'}'
    end
    query = query:gsub('FIELDLIST',fields)
    if is_string(condn.where) then
        query = query:gsub('CONDITION',condn.where)
        condn.where = nil
    else
       query = query:gsub('CONDITION','_condn(v)')
       condn.where = function_arg(0,condn.where,'condition.where must be callable')
    end
    if condn.sort_by then
        local expr,sort_var,sort_dir
        local sort_by = condn.sort_by
        local i1,i2 = sort_by:find('%s+')
        if i1 then
            sort_var,sort_dir = sort_by:sub(1,i1-1),sort_by:sub(i2+1)
        else
            sort_var = sort_by
            sort_dir = 'asc'
        end
        if sort_var:match '^%$' then sort_var = sort_var:sub(2) end
        sort_var = massage_fields(data,sort_var)
        if field_error then return nil,field_error end
        if sort_dir == 'asc' then
            sort_dir = '<'
        else
            sort_dir = '>'
        end
        expr = ('%s %s %s'):format(sort_var:gsub('v','v1'),sort_dir,sort_var:gsub('v','v2'))
        query = query:gsub('SORT_EXPR',expr)
    end
    if condn.where then
        query = 'return function(_condn) '..query..' end'
    end
    if _DEBUG then print(query) end

    local fn,err = utils.load(query,'tmp')
    if not fn then return nil,err end
    fn = fn() -- get the function
    if condn.where then
        fn = fn(condn.where)
    end
    local qfun = fn(data)
    if context then
        -- [specifying context for condition] @context is a list of tables which are
        -- 'injected'into the condition's custom context
        append(context,_G)
        local lookup = {}
        utils.setfenv(qfun,lookup)
        setmetatable(lookup,{
            __index = function(tbl,key)
               -- _G.print(tbl,key)
                for k,t in ipairs(context) do
                    if t[key] then return t[key] end
                end
            end
        })
    end
    return qfun
end


DataMT.select = data.query
DataMT.select_row = function(d,condn,context)
    return data.query(d,condn,context,true)
end

--- Filter input using a query.
-- @string Q a query string
-- @param infile filename or file-like object
-- @param outfile filename or file-like object
-- @bool dont_fail true if you want to return an error, not just fail
function data.filter (Q,infile,outfile,dont_fail)
    local d = data.read(infile or 'stdin')
    local out = open_file(outfile or 'stdout')
    local iter,err = d:select(Q)
    local delim = d.delim
    if not iter then
        err = 'error: '..err
        if dont_fail then
            return nil,err
        else
            utils.quit(1,err)
        end
    end
    while true do
        local res = {iter()}
        if #res == 0 then break end
        out:write(concat(res,delim),'\n')
    end
end

return data


end,

["pl.Date"] = function()
--------------------
-- Module: 'pl.Date'
--------------------
--- Date and Date Format classes.
-- See  @{05-dates.md|the Guide}.
--
-- NOTE: the date module is deprecated! see
-- https://github.com/lunarmodules/Penlight/issues/285
--
-- Dependencies: `pl.class`, `pl.stringx`, `pl.utils`
-- @classmod pl.Date
-- @pragma nostrip

local class = require 'pl.class'
local os_time, os_date = os.time, os.date
local stringx = require 'pl.stringx'
local utils = require 'pl.utils'
local assert_arg,assert_string = utils.assert_arg,utils.assert_string


utils.raise_deprecation {
  source = "Penlight " .. utils._VERSION,
  message = "the 'Date' module is deprecated, see https://github.com/lunarmodules/Penlight/issues/285",
  version_removed = "2.0.0",
  version_deprecated = "1.9.2",
}


local Date = class()
Date.Format = class()

--- Date constructor.
-- @param t this can be either
--
--   * `nil` or empty - use current date and time
--   * number - seconds since epoch (as returned by `os.time`). Resulting time is UTC
--   * `Date` - make a copy of this date
--   * table - table containing year, month, etc as for `os.time`. You may leave out year, month or day,
-- in which case current values will be used.
--   * year (will be followed by month, day etc)
--
-- @param ...  true if  Universal Coordinated Time, or two to five numbers: month,day,hour,min,sec
-- @function Date
function Date:_init(t,...)
    local time
    local nargs = select('#',...)
    if nargs > 2 then
        local extra = {...}
        local year = t
        t = {
            year = year,
            month = extra[1],
            day = extra[2],
            hour = extra[3],
            min = extra[4],
            sec = extra[5]
        }
    end
    if nargs == 1 then
        self.utc = select(1,...) == true
    end
    if t == nil or t == 'utc' then
        time = os_time()
        self.utc = t == 'utc'
    elseif type(t) == 'number' then
        time = t
        if self.utc == nil then self.utc = true end
    elseif type(t) == 'table' then
        if getmetatable(t) == Date then -- copy ctor
            time = t.time
            self.utc = t.utc
        else
            if not (t.year and t.month) then
                local lt = os_date('*t')
                if not t.year and not t.month and not t.day then
                    t.year = lt.year
                    t.month = lt.month
                    t.day = lt.day
                else
                    t.year = t.year or lt.year
                    t.month = t.month or (t.day and lt.month or 1)
                    t.day = t.day or 1
                end
            end
            t.day = t.day or 1
            time = os_time(t)
        end
    else
        error("bad type for Date constructor: "..type(t),2)
    end
    self:set(time)
end

--- set the current time of this Date object.
-- @int t seconds since epoch
function Date:set(t)
    self.time = t
    if self.utc then
        self.tab = os_date('!*t',t)
    else
        self.tab = os_date('*t',t)
    end
end

--- get the time zone offset from UTC.
-- @int ts seconds ahead of UTC
function Date.tzone (ts)
    if ts == nil then
        ts = os_time()
    elseif type(ts) == "table" then
        if getmetatable(ts) == Date then
            ts = ts.time
        else
            ts = Date(ts).time
        end
    end
    local utc = os_date('!*t',ts)
    local lcl = os_date('*t',ts)
    lcl.isdst = false
    return os.difftime(os_time(lcl), os_time(utc))
end

--- convert this date to UTC.
function Date:toUTC ()
    local ndate = Date(self)
    if not self.utc then
        ndate.utc = true
        ndate:set(ndate.time)
    end
    return ndate
end

--- convert this UTC date to local.
function Date:toLocal ()
    local ndate = Date(self)
    if self.utc then
        ndate.utc = false
        ndate:set(ndate.time)
--~         ndate:add { sec = Date.tzone(self) }
    end
    return ndate
end

--- set the year.
-- @int y Four-digit year
-- @class function
-- @name Date:year

--- set the month.
-- @int m month
-- @class function
-- @name Date:month

--- set the day.
-- @int d day
-- @class function
-- @name Date:day

--- set the hour.
-- @int h hour
-- @class function
-- @name Date:hour

--- set the minutes.
-- @int min minutes
-- @class function
-- @name Date:min

--- set the seconds.
-- @int sec seconds
-- @class function
-- @name Date:sec

--- set the day of year.
-- @class function
-- @int yday day of year
-- @name Date:yday

--- get the year.
-- @int y Four-digit year
-- @class function
-- @name Date:year

--- get the month.
-- @class function
-- @name Date:month

--- get the day.
-- @class function
-- @name Date:day

--- get the hour.
-- @class function
-- @name Date:hour

--- get the minutes.
-- @class function
-- @name Date:min

--- get the seconds.
-- @class function
-- @name Date:sec

--- get the day of year.
-- @class function
-- @name Date:yday


for _,c in ipairs{'year','month','day','hour','min','sec','yday'} do
    Date[c] = function(self,val)
        if val then
            assert_arg(1,val,"number")
            self.tab[c] = val
            self:set(os_time(self.tab))
            return self
        else
            return self.tab[c]
        end
    end
end

--- name of day of week.
-- @bool full abbreviated if true, full otherwise.
-- @ret string name
function Date:weekday_name(full)
    return os_date(full and '%A' or '%a',self.time)
end

--- name of month.
-- @int full abbreviated if true, full otherwise.
-- @ret string name
function Date:month_name(full)
    return os_date(full and '%B' or '%b',self.time)
end

--- is this day on a weekend?.
function Date:is_weekend()
    return self.tab.wday == 1 or self.tab.wday == 7
end

--- add to a date object.
-- @param t a table containing one of the following keys and a value:
-- one of `year`,`month`,`day`,`hour`,`min`,`sec`
-- @return this date
function Date:add(t)
    local old_dst = self.tab.isdst
    local key,val = next(t)
    self.tab[key] = self.tab[key] + val
    self:set(os_time(self.tab))
    if old_dst ~= self.tab.isdst then
        self.tab.hour = self.tab.hour - (old_dst and 1 or -1)
        self:set(os_time(self.tab))
    end
    return self
end

--- last day of the month.
-- @return int day
function Date:last_day()
    local d = 28
    local m = self.tab.month
    while self.tab.month == m do
        d = d + 1
        self:add{day=1}
    end
    self:add{day=-1}
    return self
end

--- difference between two Date objects.
-- @tparam Date other Date object
-- @treturn Date.Interval object
function Date:diff(other)
    local dt = self.time - other.time
    if dt < 0 then error("date difference is negative!",2) end
    return Date.Interval(dt)
end

--- long numerical ISO data format version of this date.
function Date:__tostring()
    local fmt = '%Y-%m-%dT%H:%M:%S'
    if self.utc then
        fmt = "!"..fmt
    end
    local t = os_date(fmt,self.time)
    if self.utc then
        return  t .. 'Z'
    else
        local offs = self:tzone()
        if offs == 0 then
            return t .. 'Z'
        end
        local sign = offs > 0 and '+' or '-'
        local h = math.ceil(offs/3600)
        local m = (offs % 3600)/60
        if m == 0 then
            return t .. ('%s%02d'):format(sign,h)
        else
            return t .. ('%s%02d:%02d'):format(sign,h,m)
        end
    end
end

--- equality between Date objects.
function Date:__eq(other)
    return self.time == other.time
end

--- ordering between Date objects.
function Date:__lt(other)
    return self.time < other.time
end

--- difference between Date objects.
-- @function Date:__sub
Date.__sub = Date.diff

--- add a date and an interval.
-- @param other either a `Date.Interval` object or a table such as
-- passed to `Date:add`
function Date:__add(other)
    local nd = Date(self)
    if Date.Interval:class_of(other) then
        other = {sec=other.time}
    end
    nd:add(other)
    return nd
end

Date.Interval = class(Date)

---- Date.Interval constructor
-- @int t an interval in seconds
-- @function Date.Interval
function Date.Interval:_init(t)
    self:set(t)
end

function Date.Interval:set(t)
    self.time = t
    self.tab = os_date('!*t',self.time)
end

local function ess(n)
    if n > 1 then return 's '
    else return ' '
    end
end

--- If it's an interval then the format is '2 hours 29 sec' etc.
function Date.Interval:__tostring()
    local t, res = self.tab, ''
    local y,m,d = t.year - 1970, t.month - 1, t.day - 1
    if y > 0 then res = res .. y .. ' year'..ess(y) end
    if m > 0 then res = res .. m .. ' month'..ess(m) end
    if d > 0 then res = res .. d .. ' day'..ess(d) end
    if y == 0 and m == 0 then
        local h = t.hour
        if h > 0 then res = res .. h .. ' hour'..ess(h) end
        if t.min > 0 then res = res .. t.min .. ' min ' end
        if t.sec > 0 then res = res .. t.sec .. ' sec ' end
    end
    if res == '' then res = 'zero' end
    return res
end

------------ Date.Format class: parsing and renderinig dates ------------

-- short field names, explicit os.date names, and a mask for allowed field repeats
local formats = {
    d = {'day',{true,true}},
    y = {'year',{false,true,false,true}},
    m = {'month',{true,true}},
    H = {'hour',{true,true}},
    M = {'min',{true,true}},
    S = {'sec',{true,true}},
}

--- Date.Format constructor.
-- @string fmt. A string where the following fields are significant:
--
--   * d day (either d or dd)
--   * y year (either yy or yyy)
--   * m month (either m or mm)
--   * H hour (either H or HH)
--   * M minute (either M or MM)
--   * S second (either S or SS)
--
-- Alternatively, if fmt is nil then this returns a flexible date parser
-- that tries various date/time schemes in turn:
--
--  * [ISO 8601](http://en.wikipedia.org/wiki/ISO_8601), like `2010-05-10 12:35:23Z` or `2008-10-03T14:30+02`
--  * times like 15:30 or 8.05pm  (assumed to be today's date)
--  * dates like 28/10/02 (European order!) or 5 Feb 2012
--  * month name like march or Mar (case-insensitive, first 3 letters); here the
-- day will be 1 and the year this current year
--
-- A date in format 3 can be optionally followed by a time in format 2.
-- Please see test-date.lua in the tests folder for more examples.
-- @usage df = Date.Format("yyyy-mm-dd HH:MM:SS")
-- @class function
-- @name Date.Format
function Date.Format:_init(fmt)
    if not fmt then
        self.fmt = '%Y-%m-%d %H:%M:%S'
        self.outf = self.fmt
        self.plain = true
        return
    end
    local append = table.insert
    local D,PLUS,OPENP,CLOSEP = '\001','\002','\003','\004'
    local vars,used = {},{}
    local patt,outf = {},{}
    local i = 1
    while i < #fmt do
        local ch = fmt:sub(i,i)
        local df = formats[ch]
        if df then
            if used[ch] then error("field appeared twice: "..ch,4) end
            used[ch] = true
            -- this field may be repeated
            local _,inext = fmt:find(ch..'+',i+1)
            local cnt = not _ and 1 or inext-i+1
            if not df[2][cnt] then error("wrong number of fields: "..ch,4) end
            -- single chars mean 'accept more than one digit'
            local p = cnt==1 and (D..PLUS) or (D):rep(cnt)
            append(patt,OPENP..p..CLOSEP)
            append(vars,ch)
            if ch == 'y' then
                append(outf,cnt==2 and '%y' or '%Y')
            else
                append(outf,'%'..ch)
            end
            i = i + cnt
        else
            append(patt,ch)
            append(outf,ch)
            i = i + 1
        end
    end
    -- escape any magic characters
    fmt = utils.escape(table.concat(patt))
   -- fmt = table.concat(patt):gsub('[%-%.%+%[%]%(%)%$%^%%%?%*]','%%%1')
    -- replace markers with their magic equivalents
    fmt = fmt:gsub(D,'%%d'):gsub(PLUS,'+'):gsub(OPENP,'('):gsub(CLOSEP,')')
    self.fmt = fmt
    self.outf = table.concat(outf)
    self.vars = vars
end

local parse_date

--- parse a string into a Date object.
-- @string str a date string
-- @return date object
function Date.Format:parse(str)
    assert_string(1,str)
    if self.plain then
        return parse_date(str,self.us)
    end
    local res = {str:match(self.fmt)}
    if #res==0 then return nil, 'cannot parse '..str end
    local tab = {}
    for i,v in ipairs(self.vars) do
        local name = formats[v][1] -- e.g. 'y' becomes 'year'
        tab[name] = tonumber(res[i])
    end
    -- os.date() requires these fields; if not present, we assume
    -- that the time set is for the current day.
    if not (tab.year and tab.month and tab.day) then
        local today = Date()
        tab.year = tab.year or today:year()
        tab.month = tab.month or today:month()
        tab.day = tab.day or today:day()
    end
    local Y = tab.year
    if Y < 100 then -- classic Y2K pivot
        tab.year = Y + (Y < 35 and 2000 or 1999)
    elseif not Y then
        tab.year = 1970
    end
    return Date(tab)
end

--- convert a Date object into a string.
-- @param d a date object, or a time value as returned by @{os.time}
-- @return string
function Date.Format:tostring(d)
    local tm
    local fmt = self.outf
    if type(d) == 'number' then
        tm = d
    else
        tm = d.time
        if d.utc then
            fmt = '!'..fmt
        end
    end
    return os_date(fmt,tm)
end

--- force US order in dates like 9/11/2001
function Date.Format:US_order(yesno)
    self.us = yesno
end

--local months = {jan=1,feb=2,mar=3,apr=4,may=5,jun=6,jul=7,aug=8,sep=9,oct=10,nov=11,dec=12}
local months
local parse_date_unsafe
local function create_months()
    local ld, day1 = parse_date_unsafe '2000-12-31', {day=1}
    months = {}
    for i = 1,12 do
        ld = ld:last_day()
        ld:add(day1)
        local mon = ld:month_name():lower()
        months [mon] = i
    end
end

--[[
Allowed patterns:
- [day] [monthname] [year] [time]
- [day]/[month][/year] [time]

]]

local function looks_like_a_month(w)
    return w:match '^%a+,*$' ~= nil
end
local is_number = stringx.isdigit
local function tonum(s,l1,l2,kind)
    kind = kind or ''
    local n = tonumber(s)
    if not n then error(("%snot a number: '%s'"):format(kind,s)) end
    if n < l1 or n > l2 then
        error(("%s out of range: %s is not between %d and %d"):format(kind,s,l1,l2))
    end
    return n
end

local function  parse_iso_end(p,ns,sec)
    -- may be fractional part of seconds
    local _,nfrac,secfrac = p:find('^%.%d+',ns+1)
    if secfrac then
        sec = sec .. secfrac
        p = p:sub(nfrac+1)
    else
        p = p:sub(ns+1)
    end
    -- ISO 8601 dates may end in Z (for UTC) or [+-][isotime]
    -- (we're working with the date as lower case, hence 'z')
    if p:match 'z$' then -- we're UTC!
        return  sec, {h=0,m=0}
    end
    p = p:gsub(':','') -- turn 00:30 to 0030
    local _,_,sign,offs = p:find('^([%+%-])(%d+)')
    if not sign then return sec, nil end -- not UTC

    if #offs == 2 then offs = offs .. '00' end -- 01 to 0100
    local tz = { h = tonumber(offs:sub(1,2)), m = tonumber(offs:sub(3,4)) }
    if sign == '-' then tz.h = -tz.h; tz.m = -tz.m end
    return sec, tz
end

function parse_date_unsafe (s,US)
    s = s:gsub('T',' ') -- ISO 8601
    local parts = stringx.split(s:lower())
    local i,p = 1,parts[1]
    local function nextp() i = i + 1; p = parts[i] end
    local year,min,hour,sec,apm
    local tz
    local _,nxt,day, month = p:find '^(%d+)/(%d+)'
    if day then
        -- swop for US case
        if US then
            day, month = month, day
        end
        _,_,year = p:find('^/(%d+)',nxt+1)
        nextp()
    else -- ISO
        year,month,day = p:match('^(%d+)%-(%d+)%-(%d+)')
        if year then
            nextp()
        end
    end
    if p and not year and is_number(p) then -- has to be date
        if #p < 4 then
            day = p
            nextp()
        else -- unless it looks like a 24-hour time
            year = true
        end
    end
    if p and looks_like_a_month(p) then -- date followed by month
        p = p:sub(1,3)
        if not months then
            create_months()
        end
        local mon = months[p]
        if mon then
            month = mon
        else error("not a month: " .. p) end
        nextp()
    end
    if p and not year and is_number(p) then
        year = p
        nextp()
    end

    if p then -- time is hh:mm[:ss], hhmm[ss] or H.M[am|pm]
        _,nxt,hour,min = p:find '^(%d+):(%d+)'
        local ns
        if nxt then -- are there seconds?
            _,ns,sec = p:find ('^:(%d+)',nxt+1)
            --if ns then
                sec,tz = parse_iso_end(p,ns or nxt,sec)
            --end
        else -- might be h.m
            _,ns,hour,min = p:find '^(%d+)%.(%d+)'
            if ns then
                apm = p:match '[ap]m$'
            else  -- or hhmm[ss]
                local hourmin
                _,nxt,hourmin = p:find ('^(%d+)')
                if nxt then
                   hour = hourmin:sub(1,2)
                   min = hourmin:sub(3,4)
                   sec = hourmin:sub(5,6)
                   if #sec == 0 then sec = nil end
                   sec,tz = parse_iso_end(p,nxt,sec)
                end
            end
        end
    end
    local today
    if year == true then year = nil end
    if not (year and month and day) then
        today = Date()
    end
    day = day and tonum(day,1,31,'day') or (month and 1 or today:day())
    month = month and tonum(month,1,12,'month') or today:month()
    year = year and tonumber(year) or today:year()
    if year < 100 then -- two-digit year pivot around year < 2035
        year = year + (year < 35 and 2000 or 1900)
    end
    hour = hour and tonum(hour,0,apm and 12 or 24,'hour') or 12
    if apm == 'pm' then
        hour = hour + 12
    end
    min = min and tonum(min,0,59) or 0
    sec = sec and tonum(sec,0,60) or 0  --60 used to indicate leap second
    local res = Date {year = year, month = month, day = day, hour = hour, min = min, sec = sec}
    if tz then -- ISO 8601 UTC time
        local corrected = false
        if tz.h ~= 0 then res:add {hour = -tz.h}; corrected = true end
        if tz.m ~= 0 then res:add {min = -tz.m}; corrected = true end
        res.utc = true
        -- we're in UTC, so let's go local...
        if corrected then
            res = res:toLocal()
        end-- we're UTC!
    end
    return res
end

function parse_date (s)
    local ok, d = pcall(parse_date_unsafe,s)
    if not ok then -- error
        d = d:gsub('.-:%d+: ','')
        return nil, d
    else
        return d
    end
end

return Date


end,

["pl.dir"] = function()
--------------------
-- Module: 'pl.dir'
--------------------
--- Listing files in directories and creating/removing directory paths.
--
-- Dependencies: `pl.utils`, `pl.path`
--
-- Soft Dependencies: `alien`, `ffi` (either are used on Windows for copying/moving files)
-- @module pl.dir

local utils = require 'pl.utils'
local path = require 'pl.path'
local is_windows = path.is_windows
local ldir = path.dir
local mkdir = path.mkdir
local rmdir = path.rmdir
local sub = string.sub
local os,pcall,ipairs,pairs,require,setmetatable = os,pcall,ipairs,pairs,require,setmetatable
local remove = os.remove
local append = table.insert
local assert_arg,assert_string,raise = utils.assert_arg,utils.assert_string,utils.raise

local exists, isdir = path.exists, path.isdir
local sep = path.sep

local dir = {}

local function makelist(l)
    return setmetatable(l, require('pl.List'))
end

local function assert_dir (n,val)
    assert_arg(n,val,'string',path.isdir,'not a directory',4)
end

local function filemask(mask)
    mask = utils.escape(path.normcase(mask))
    return '^'..mask:gsub('%%%*','.*'):gsub('%%%?','.')..'$'
end

--- Test whether a file name matches a shell pattern.
-- Both parameters are case-normalized if operating system is
-- case-insensitive.
-- @string filename A file name.
-- @string pattern A shell pattern. The only special characters are
-- `'*'` and `'?'`: `'*'` matches any sequence of characters and
-- `'?'` matches any single character.
-- @treturn bool
-- @raise dir and mask must be strings
function dir.fnmatch(filename,pattern)
    assert_string(1,filename)
    assert_string(2,pattern)
    return path.normcase(filename):find(filemask(pattern)) ~= nil
end

--- Return a list of all file names within an array which match a pattern.
-- @tab filenames An array containing file names.
-- @string pattern A shell pattern (see `fnmatch`).
-- @treturn List(string) List of matching file names.
-- @raise dir and mask must be strings
function dir.filter(filenames,pattern)
    assert_arg(1,filenames,'table')
    assert_string(2,pattern)
    local res = {}
    local mask = filemask(pattern)
    for i,f in ipairs(filenames) do
        if path.normcase(f):find(mask) then append(res,f) end
    end
    return makelist(res)
end

local function _listfiles(dirname,filemode,match)
    local res = {}
    local check = utils.choose(filemode,path.isfile,path.isdir)
    if not dirname then dirname = '.' end
    for f in ldir(dirname) do
        if f ~= '.' and f ~= '..' then
            local p = path.join(dirname,f)
            if check(p) and (not match or match(f)) then
                append(res,p)
            end
        end
    end
    return makelist(res)
end

--- return a list of all files in a directory which match a shell pattern.
-- @string[opt='.'] dirname A directory.
-- @string[opt] mask A shell pattern (see `fnmatch`). If not given, all files are returned.
-- @treturn {string} list of files
-- @raise dirname and mask must be strings
function dir.getfiles(dirname,mask)
    dirname = dirname or '.'
    assert_dir(1,dirname)
    if mask then assert_string(2,mask) end
    local match
    if mask then
        mask = filemask(mask)
        match = function(f)
            return path.normcase(f):find(mask)
        end
    end
    return _listfiles(dirname,true,match)
end

--- return a list of all subdirectories of the directory.
-- @string[opt='.'] dirname A directory.
-- @treturn {string} a list of directories
-- @raise dir must be a valid directory
function dir.getdirectories(dirname)
    dirname = dirname or '.'
    assert_dir(1,dirname)
    return _listfiles(dirname,false)
end

local alien,ffi,ffi_checked,CopyFile,MoveFile,GetLastError,win32_errors,cmd_tmpfile

local function execute_command(cmd,parms)
   if not cmd_tmpfile then cmd_tmpfile = path.tmpname () end
   local err = path.is_windows and ' > ' or ' 2> '
    cmd = cmd..' '..parms..err..utils.quote_arg(cmd_tmpfile)
    local ret = utils.execute(cmd)
    if not ret then
        local err = (utils.readfile(cmd_tmpfile):gsub('\n(.*)',''))
        remove(cmd_tmpfile)
        return false,err
    else
        remove(cmd_tmpfile)
        return true
    end
end

local function find_ffi_copyfile ()
    if not ffi_checked then
        ffi_checked = true
        local res
        res,alien = pcall(require,'alien')
        if not res then
            alien = nil
            res, ffi = pcall(require,'ffi')
        end
        if not res then
            ffi = nil
            return
        end
    else
        return
    end
    if alien then
        -- register the Win32 CopyFile and MoveFile functions
        local kernel = alien.load('kernel32.dll')
        CopyFile = kernel.CopyFileA
        CopyFile:types{'string','string','int',ret='int',abi='stdcall'}
        MoveFile = kernel.MoveFileA
        MoveFile:types{'string','string',ret='int',abi='stdcall'}
        GetLastError = kernel.GetLastError
        GetLastError:types{ret ='int', abi='stdcall'}
    elseif ffi then
        ffi.cdef [[
            int CopyFileA(const char *src, const char *dest, int iovr);
            int MoveFileA(const char *src, const char *dest);
            int GetLastError();
        ]]
        CopyFile = ffi.C.CopyFileA
        MoveFile = ffi.C.MoveFileA
        GetLastError = ffi.C.GetLastError
    end
    win32_errors = {
        ERROR_FILE_NOT_FOUND    =         2,
        ERROR_PATH_NOT_FOUND    =         3,
        ERROR_ACCESS_DENIED    =          5,
        ERROR_WRITE_PROTECT    =          19,
        ERROR_BAD_UNIT         =          20,
        ERROR_NOT_READY        =          21,
        ERROR_WRITE_FAULT      =          29,
        ERROR_READ_FAULT       =          30,
        ERROR_SHARING_VIOLATION =         32,
        ERROR_LOCK_VIOLATION    =         33,
        ERROR_HANDLE_DISK_FULL  =         39,
        ERROR_BAD_NETPATH       =         53,
        ERROR_NETWORK_BUSY      =         54,
        ERROR_DEV_NOT_EXIST     =         55,
        ERROR_FILE_EXISTS       =         80,
        ERROR_OPEN_FAILED       =         110,
        ERROR_INVALID_NAME      =         123,
        ERROR_BAD_PATHNAME      =         161,
        ERROR_ALREADY_EXISTS    =         183,
    }
end

local function two_arguments (f1,f2)
    return utils.quote_arg(f1)..' '..utils.quote_arg(f2)
end

local function file_op (is_copy,src,dest,flag)
    if flag == 1 and path.exists(dest) then
        return false,"cannot overwrite destination"
    end
    if is_windows then
        -- if we haven't tried to load Alien/LuaJIT FFI before, then do so
        find_ffi_copyfile()
        -- fallback if there's no Alien, just use DOS commands *shudder*
        -- 'rename' involves a copy and then deleting the source.
        if not CopyFile then
            if path.is_windows then
                src = src:gsub("/","\\")
                dest = dest:gsub("/","\\")
            end
            local res, err = execute_command('copy',two_arguments(src,dest))
            if not res then return false,err end
            if not is_copy then
                return execute_command('del',utils.quote_arg(src))
            end
            return true
        else
            if path.isdir(dest) then
                dest = path.join(dest,path.basename(src))
            end
            local ret
            if is_copy then ret = CopyFile(src,dest,flag)
            else ret = MoveFile(src,dest) end
            if ret == 0 then
                local err = GetLastError()
                for name,value in pairs(win32_errors) do
                    if value == err then return false,name end
                end
                return false,"Error #"..err
            else return true
            end
        end
    else -- for Unix, just use cp for now
        return execute_command(is_copy and 'cp' or 'mv',
            two_arguments(src,dest))
    end
end

--- copy a file.
-- @string src source file
-- @string dest destination file or directory
-- @bool flag true if you want to force the copy (default)
-- @treturn bool operation succeeded
-- @raise src and dest must be strings
function dir.copyfile (src,dest,flag)
    assert_string(1,src)
    assert_string(2,dest)
    flag = flag==nil or flag
    return file_op(true,src,dest,flag and 0 or 1)
end

--- move a file.
-- @string src source file
-- @string dest destination file or directory
-- @treturn bool operation succeeded
-- @raise src and dest must be strings
function dir.movefile (src,dest)
    assert_string(1,src)
    assert_string(2,dest)
    return file_op(false,src,dest,0)
end

local function _dirfiles(dirname,attrib)
    local dirs = {}
    local files = {}
    for f in ldir(dirname) do
        if f ~= '.' and f ~= '..' then
            local p = path.join(dirname,f)
            local mode = attrib(p,'mode')
            if mode=='directory' then
                append(dirs,f)
            else
                append(files,f)
            end
        end
    end
    return makelist(dirs), makelist(files)
end


--- return an iterator which walks through a directory tree starting at root.
-- The iterator returns (root,dirs,files)
-- Note that dirs and files are lists of names (i.e. you must say path.join(root,d)
-- to get the actual full path)
-- If bottom_up is false (or not present), then the entries at the current level are returned
-- before we go deeper. This means that you can modify the returned list of directories before
-- continuing.
-- This is a clone of os.walk from the Python libraries.
-- @string root A starting directory
-- @bool bottom_up False if we start listing entries immediately.
-- @bool follow_links follow symbolic links
-- @return an iterator returning root,dirs,files
-- @raise root must be a directory
function dir.walk(root,bottom_up,follow_links)
    assert_dir(1,root)
    local attrib
    if path.is_windows or not follow_links then
        attrib = path.attrib
    else
        attrib = path.link_attrib
    end

    local to_scan = { root }
    local to_return = {}
    local iter = function()
        while #to_scan > 0 do
            local current_root = table.remove(to_scan)
            local dirs,files = _dirfiles(current_root, attrib)
            for _, d in ipairs(dirs) do
                table.insert(to_scan, current_root..path.sep..d)
            end
            if not bottom_up then
                return current_root, dirs, files
            else
                table.insert(to_return, { current_root, dirs, files })
            end
        end
        if #to_return > 0 then
            return utils.unpack(table.remove(to_return))
        end
    end

    return iter
end

--- remove a whole directory tree.
-- Symlinks in the tree will be deleted without following them.
-- @string fullpath A directory path (must be an actual directory, not a symlink)
-- @return true or nil
-- @return error if failed
-- @raise fullpath must be a string
function dir.rmtree(fullpath)
    assert_dir(1,fullpath)
    if path.islink(fullpath) then return false,'will not follow symlink' end
    for root,dirs,files in dir.walk(fullpath,true) do
        if path.islink(root) then
            -- sub dir is a link, remove link, do not follow
            if is_windows then
                -- Windows requires using "rmdir". Deleting the link like a file
                -- will instead delete all files from the target directory!!
                local res, err = rmdir(root)
                if not res then return nil,err .. ": " .. root end
            else
                local res, err = remove(root)
                if not res then return nil,err .. ": " .. root end
            end
        else
            for i,f in ipairs(files) do
                local res, err = remove(path.join(root,f))
                if not res then return nil,err .. ": " .. path.join(root,f) end
            end
            local res, err = rmdir(root)
            if not res then return nil,err .. ": " .. root end
        end
    end
    return true
end


do
  local dirpat
  if path.is_windows then
      dirpat = '(.+)\\[^\\]+$'
  else
      dirpat = '(.+)/[^/]+$'
  end

  local _makepath
  function _makepath(p)
      -- windows root drive case
      if p:find '^%a:[\\]*$' then
          return true
      end
      if not path.isdir(p) then
          local subp = p:match(dirpat)
          if subp then
            local ok, err = _makepath(subp)
            if not ok then return nil, err end
          end
          return mkdir(p)
      else
          return true
      end
  end

  --- create a directory path.
  -- This will create subdirectories as necessary!
  -- @string p A directory path
  -- @return true on success, nil + errormsg on failure
  -- @raise failure to create
  function dir.makepath (p)
      assert_string(1,p)
      if path.is_windows then
          p = p:gsub("/", "\\")
      end
      return _makepath(path.abspath(p))
  end
end

--- clone a directory tree. Will always try to create a new directory structure
-- if necessary.
-- @string path1 the base path of the source tree
-- @string path2 the new base path for the destination
-- @func file_fun an optional function to apply on all files
-- @bool verbose an optional boolean to control the verbosity of the output.
--  It can also be a logging function that behaves like print()
-- @return true, or nil
-- @return error message, or list of failed directory creations
-- @return list of failed file operations
-- @raise path1 and path2 must be strings
-- @usage clonetree('.','../backup',copyfile)
function dir.clonetree (path1,path2,file_fun,verbose)
    assert_string(1,path1)
    assert_string(2,path2)
    if verbose == true then verbose = print end
    local abspath,normcase,isdir,join = path.abspath,path.normcase,path.isdir,path.join
    local faildirs,failfiles = {},{}
    if not isdir(path1) then return raise 'source is not a valid directory' end
    path1 = abspath(normcase(path1))
    path2 = abspath(normcase(path2))
    if verbose then verbose('normalized:',path1,path2) end
    -- particularly NB that the new path isn't fully contained in the old path
    if path1 == path2 then return raise "paths are the same" end
    local _,i2 = path2:find(path1,1,true)
    if i2 == #path1 and path2:sub(i2+1,i2+1) == path.sep then
        return raise 'destination is a subdirectory of the source'
    end
    local cp = path.common_prefix (path1,path2)
    local idx = #cp
    if idx == 0 then -- no common path, but watch out for Windows paths!
        if path1:sub(2,2) == ':' then idx = 3 end
    end
    for root,dirs,files in dir.walk(path1) do
        local opath = path2..root:sub(idx)
        if verbose then verbose('paths:',opath,root) end
        if not isdir(opath) then
            local ret = dir.makepath(opath)
            if not ret then append(faildirs,opath) end
            if verbose then verbose('creating:',opath,ret) end
        end
        if file_fun then
            for i,f in ipairs(files) do
                local p1 = join(root,f)
                local p2 = join(opath,f)
                local ret = file_fun(p1,p2)
                if not ret then append(failfiles,p2) end
                if verbose then
                    verbose('files:',p1,p2,ret)
                end
            end
        end
    end
    return true,faildirs,failfiles
end


-- each entry of the stack is an array with three items:
-- 1. the name of the directory
-- 2. the lfs iterator function
-- 3. the lfs iterator userdata
local function treeiter(iterstack)
    local diriter = iterstack[#iterstack]
    if not diriter then
      return -- done
    end

    local dirname = diriter[1]
    local entry = diriter[2](diriter[3])
    if not entry then
      table.remove(iterstack)
      return treeiter(iterstack) -- tail-call to try next
    end

    if entry ~= "." and entry ~= ".." then
        entry = dirname .. sep .. entry
        if exists(entry) then  -- Just in case a symlink is broken.
            local is_dir = isdir(entry)
            if is_dir then
                table.insert(iterstack, { entry, ldir(entry) })
            end
            return entry, is_dir
        end
    end

    return treeiter(iterstack) -- tail-call to try next
end


--- return an iterator over all entries in a directory tree
-- @string d a directory
-- @return an iterator giving pathname and mode (true for dir, false otherwise)
-- @raise d must be a non-empty string
function dir.dirtree( d )
    assert( d and d ~= "", "directory parameter is missing or empty" )

    local last = sub ( d, -1 )
    if last == sep or last == '/' then
        d = sub( d, 1, -2 )
    end

    local iterstack = { {d, ldir(d)} }

    return treeiter, iterstack
end


--- Recursively returns all the file starting at 'path'. It can optionally take a shell pattern and
-- only returns files that match 'shell_pattern'. If a pattern is given it will do a case insensitive search.
-- @string[opt='.'] start_path  A directory.
-- @string[opt='*'] shell_pattern A shell pattern (see `fnmatch`).
-- @treturn List(string) containing all the files found recursively starting at 'path' and filtered by 'shell_pattern'.
-- @raise start_path must be a directory
function dir.getallfiles( start_path, shell_pattern )
    start_path = start_path or '.'
    assert_dir(1,start_path)
    shell_pattern = shell_pattern or "*"

    local files = {}
    local normcase = path.normcase
    for filename, mode in dir.dirtree( start_path ) do
        if not mode then
            local mask = filemask( shell_pattern )
            if normcase(filename):find( mask ) then
                files[#files + 1] = filename
            end
        end
    end

    return makelist(files)
end

return dir

end,

["pl.file"] = function()
--------------------
-- Module: 'pl.file'
--------------------
--- File manipulation functions: reading, writing, moving and copying.
--
-- This module wraps a number of functions from other modules into a
-- file related module for convenience.
--
-- Dependencies: `pl.utils`, `pl.dir`, `pl.path`
-- @module pl.file
local os = os
local utils = require 'pl.utils'
local dir = require 'pl.dir'
local path = require 'pl.path'

local file = {}

--- return the contents of a file as a string.
-- This function is a copy of `utils.readfile`.
-- @function file.read
file.read = utils.readfile

--- write a string to a file.
-- This function is a copy of `utils.writefile`.
-- @function file.write
file.write = utils.writefile

--- copy a file.
-- This function is a copy of `dir.copyfile`.
-- @function file.copy
file.copy = dir.copyfile

--- move a file.
-- This function is a copy of `dir.movefile`.
-- @function file.move
file.move = dir.movefile

--- Return the time of last access as the number of seconds since the epoch.
-- This function is a copy of `path.getatime`.
-- @function file.access_time
file.access_time = path.getatime

---Return when the file was created.
-- This function is a copy of `path.getctime`.
-- @function file.creation_time
file.creation_time = path.getctime

--- Return the time of last modification.
-- This function is a copy of `path.getmtime`.
-- @function file.modified_time
file.modified_time = path.getmtime

--- Delete a file.
-- This function is a copy of `os.remove`.
-- @function file.delete
file.delete = os.remove

return file

end,

["pl.func"] = function()
--------------------
-- Module: 'pl.func'
--------------------
--- Functional helpers like composition, binding and placeholder expressions.
-- Placeholder expressions are useful for short anonymous functions, and were
-- inspired by the Boost Lambda library.
--
--    > utils.import 'pl.func'
--    > ls = List{10,20,30}
--    > = ls:map(_1+1)
--    {11,21,31}
--
-- They can also be used to _bind_ particular arguments of a function.
--
--    > p = bind(print,'start>',_0)
--    > p(10,20,30)
--    > start>   10   20  30
--
-- See @{07-functional.md.Creating_Functions_from_Functions|the Guide}
--
-- Dependencies: `pl.utils`, `pl.tablex`
-- @module pl.func
local type,setmetatable,getmetatable,rawset = type,setmetatable,getmetatable,rawset
local concat,append = table.concat,table.insert
local tostring = tostring
local utils = require 'pl.utils'
local pairs,rawget,unpack,pack = pairs,rawget,utils.unpack,utils.pack
local tablex = require 'pl.tablex'
local map = tablex.map
local _DEBUG = rawget(_G,'_DEBUG')
local assert_arg = utils.assert_arg

local func = {}

-- metatable for Placeholder Expressions (PE)
local _PEMT = {}

local function P (t)
    setmetatable(t,_PEMT)
    return t
end

func.PE = P

local function isPE (obj)
    return getmetatable(obj) == _PEMT
end

func.isPE = isPE

-- construct a placeholder variable (e.g _1 and _2)
local function PH (idx)
    return P {op='X',repr='_'..idx, index=idx}
end

-- construct a constant placeholder variable (e.g _C1 and _C2)
local function CPH (idx)
    return P {op='X',repr='_C'..idx, index=idx}
end

func._1,func._2,func._3,func._4,func._5 = PH(1),PH(2),PH(3),PH(4),PH(5)
func._0 = P{op='X',repr='...',index=0}

function func.Var (name)
    local ls = utils.split(name,'[%s,]+')
    local res = {}
    for i = 1, #ls do
        append(res,P{op='X',repr=ls[i],index=0})
    end
    return unpack(res)
end

function func._ (value)
    return P{op='X',repr=value,index='wrap'}
end

local repr

func.Nil = func.Var 'nil'

function _PEMT.__index(obj,key)
    return P{op='[]',obj,key}
end

function _PEMT.__call(fun,...)
    return P{op='()',fun,...}
end

function _PEMT.__tostring (e)
    return repr(e)
end

function _PEMT.__unm(arg)
    return P{op='unm',arg}
end

function func.Not (arg)
    return P{op='not',arg}
end

function func.Len (arg)
    return P{op='#',arg}
end


local function binreg(context,t)
    for name,op in pairs(t) do
        rawset(context,name,function(x,y)
            return P{op=op,x,y}
        end)
    end
end

local function import_name (name,fun,context)
    rawset(context,name,function(...)
        return P{op='()',fun,...}
    end)
end

local imported_functions = {}

local function is_global_table (n)
    return type(_G[n]) == 'table'
end

--- wrap a table of functions. This makes them available for use in
-- placeholder expressions.
-- @string tname a table name
-- @tab context context to put results, defaults to environment of caller
function func.import(tname,context)
    assert_arg(1,tname,'string',is_global_table,'arg# 1: not a name of a global table')
    local t = _G[tname]
    context = context or _G
    for name,fun in pairs(t) do
        import_name(name,fun,context)
        imported_functions[fun] = name
    end
end

--- register a function for use in placeholder expressions.
-- @func fun a function
-- @string[opt] name an optional name
-- @return a placeholder functiond
function func.register (fun,name)
    assert_arg(1,fun,'function')
    if name then
        assert_arg(2,name,'string')
        imported_functions[fun] = name
    end
    return function(...)
        return P{op='()',fun,...}
    end
end

function func.lookup_imported_name (fun)
    return imported_functions[fun]
end

local function _arg(...) return ... end

function func.Args (...)
    return P{op='()',_arg,...}
end

-- binary operators with their precedences (see Lua manual)
-- precedences might be incremented by one before use depending on
-- left- or right-associativity, space them out
local binary_operators = {
    ['or'] = 0,
    ['and'] = 2,
    ['=='] = 4, ['~='] = 4, ['<'] = 4, ['>'] = 4,  ['<='] = 4,   ['>='] = 4,
    ['..'] = 6,
    ['+'] = 8, ['-'] = 8,
    ['*'] = 10, ['/'] = 10, ['%'] = 10,
    ['^'] = 14
}

-- unary operators with their precedences
local unary_operators = {
    ['not'] = 12, ['#'] = 12, ['unm'] = 12
}

-- comparisons (as prefix functions)
binreg (func,{And='and',Or='or',Eq='==',Lt='<',Gt='>',Le='<=',Ge='>='})

-- standard binary operators (as metamethods)
binreg (_PEMT,{__add='+',__sub='-',__mul='*',__div='/',__mod='%',__pow='^',__concat='..'})

binreg (_PEMT,{__eq='=='})

--- all elements of a table except the first.
-- @tab ls a list-like table.
function func.tail (ls)
    assert_arg(1,ls,'table')
    local res = {}
    for i = 2,#ls do
        append(res,ls[i])
    end
    return res
end

--- create a string representation of a placeholder expression.
-- @param e a placeholder expression
-- @param lastpred not used
function repr (e,lastpred)
    local tail = func.tail
    if isPE(e) then
        local pred = binary_operators[e.op] or unary_operators[e.op]
        if pred then
            -- binary or unary operator
            local s
            if binary_operators[e.op] then
                local left_pred = pred
                local right_pred = pred
                if e.op == '..' or e.op == '^' then
                    left_pred = left_pred + 1
                else
                    right_pred = right_pred + 1
                end
                local left_arg = repr(e[1], left_pred)
                local right_arg = repr(e[2], right_pred)
                s = left_arg..' '..e.op..' '..right_arg
            else
                local op = e.op == 'unm' and '-' or e.op
                s = op..' '..repr(e[1], pred)
            end
            if lastpred and lastpred > pred then
                s = '('..s..')'
            end
            return s
        else -- either postfix, or a placeholder
            local ls = map(repr,e)
            if e.op == '[]' then
                return ls[1]..'['..ls[2]..']'
            elseif e.op == '()' then
                local fn
                if ls[1] ~= nil then -- was _args, undeclared!
                    fn = ls[1]
                else
                    fn = ''
                end
                return fn..'('..concat(tail(ls),',')..')'
            else
                return e.repr
            end
        end
    elseif type(e) == 'string' then
        return '"'..e..'"'
    elseif type(e) == 'function' then
        local name = func.lookup_imported_name(e)
        if name then return name else return tostring(e) end
    else
        return tostring(e) --should not really get here!
    end
end
func.repr = repr

-- collect all the non-PE values in this PE into vlist, and replace each occurence
-- with a constant PH (_C1, etc). Return the maximum placeholder index found.
local collect_values
function collect_values (e,vlist)
    if isPE(e) then
        if e.op ~= 'X' then
            local m = 0
            for i = 1,#e do
                local subx = e[i]
                local pe = isPE(subx)
                if pe then
                    if subx.op == 'X' and subx.index == 'wrap' then
                        subx = subx.repr
                        pe = false
                    else
                        m = math.max(m,collect_values(subx,vlist))
                    end
                end
                if not pe then
                    append(vlist,subx)
                    e[i] = CPH(#vlist)
                end
            end
            return m
        else -- was a placeholder, it has an index...
            return e.index
        end
    else -- plain value has no placeholder dependence
        return 0
    end
end
func.collect_values = collect_values

--- instantiate a PE into an actual function. First we find the largest placeholder used,
-- e.g. _2; from this a list of the formal parameters can be build. Then we collect and replace
-- any non-PE values from the PE, and build up a constant binding list.
-- Finally, the expression can be compiled, and e.__PE_function is set.
-- @param e a placeholder expression
-- @return a function
function func.instantiate (e)
    local consts,values,parms = {},{},{}
    local rep, err, fun
    local n = func.collect_values(e,values)
    for i = 1,#values do
        append(consts,'_C'..i)
        if _DEBUG then print(i,values[i]) end
    end
    for i =1,n do
        append(parms,'_'..i)
    end
    consts = concat(consts,',')
    parms = concat(parms,',')
    rep = repr(e)
    local fstr = ('return function(%s) return function(%s) return %s end end'):format(consts,parms,rep)
    if _DEBUG then print(fstr) end
    fun,err = utils.load(fstr,'fun')
    if not fun then return nil,err end
    fun = fun()  -- get wrapper
    fun = fun(unpack(values)) -- call wrapper (values could be empty)
    e.__PE_function = fun
    return fun
end

--- instantiate a PE unless it has already been done.
-- @param e a placeholder expression
-- @return the function
function func.I(e)
    if rawget(e,'__PE_function')  then
        return e.__PE_function
    else return func.instantiate(e)
    end
end

utils.add_function_factory(_PEMT,func.I)

--- bind the first parameter of the function to a value.
-- @function func.bind1
-- @func fn a function of one or more arguments
-- @param p a value
-- @return a function of one less argument
-- @usage (bind1(math.max,10))(20) == math.max(10,20)
func.bind1 = utils.bind1
func.curry = func.bind1

--- create a function which chains two functions.
-- @func f a function of at least one argument
-- @func g a function of at least one argument
-- @return a function
-- @usage printf = compose(io.write,string.format)
function func.compose (f,g)
    return function(...) return f(g(...)) end
end

--- bind the arguments of a function to given values.
-- `bind(fn,v,_2)` is equivalent to `bind1(fn,v)`.
-- @func fn a function of at least one argument
-- @param ... values or placeholder variables
-- @return a function
-- @usage (bind(f,_1,a))(b) == f(a,b)
-- @usage (bind(f,_2,_1))(a,b) == f(b,a)
function func.bind(fn,...)
    local args = pack(...)
    local holders,parms,bvalues,values = {},{},{'fn'},{}
    local nv,maxplace,varargs = 1,0,false
    for i = 1,args.n do
        local a = args[i]
        if isPE(a) and a.op == 'X' then
            append(holders,a.repr)
            maxplace = math.max(maxplace,a.index)
            if a.index == 0 then varargs = true end
        else
            local v = '_v'..nv
            append(bvalues,v)
            append(holders,v)
            append(values,a)
            nv = nv + 1
        end
    end
    for np = 1,maxplace do
        append(parms,'_'..np)
    end
    if varargs then append(parms,'...') end
    bvalues = concat(bvalues,',')
    parms = concat(parms,',')
    holders = concat(holders,',')
    local fstr = ([[
return function (%s)
    return function(%s) return fn(%s) end
end
]]):format(bvalues,parms,holders)
    if _DEBUG then print(fstr) end
    local res = utils.load(fstr)
    res = res()
    return res(fn,unpack(values))
end

return func



end,

["pl.import_into"] = function()
--------------------
-- Module: 'pl.import_into'
--------------------
--------------
-- PL loader, for loading all PL libraries, only on demand.
-- Whenever a module is implicitly accesssed, the table will have the module automatically injected.
-- (e.g. `_ENV.tablex`)
-- then that module is dynamically loaded. The submodules are all brought into
-- the table that is provided as the argument, or returned in a new table.
-- If a table is provided, that table's metatable is clobbered, but the values are not.
-- This module returns a single function, which is passed the environment.
-- If this is `true`, then return a 'shadow table' as the module
-- See @{01-introduction.md.To_Inject_or_not_to_Inject_|the Guide}

-- @module pl.import_into

return function(env)
    local mod
    if env == true then
        mod = {}
        env = {}
    end
    local env = env or {}

    local modules = {
        utils = true,path=true,dir=true,tablex=true,stringio=true,sip=true,
        input=true,seq=true,lexer=true,stringx=true,
        config=true,pretty=true,data=true,func=true,text=true,
        operator=true,lapp=true,array2d=true,
        comprehension=true,xml=true,types=true,
        test = true, app = true, file = true, class = true,
        luabalanced = true, permute = true, template = true,
        url = true, compat = true,
        -- classes --
        List = true, Map = true, Set = true,
        OrderedMap = true, MultiMap = true, Date = true,
    }
    rawset(env,'utils',require 'pl.utils')

    for name,klass in pairs(env.utils.stdmt) do
        klass.__index = function(t,key)
            return require ('pl.'..name)[key]
        end;
    end

    -- ensure that we play nice with libraries that also attach a metatable
    -- to the global table; always forward to a custom __index if we don't
    -- match

    local _hook,_prev_index
    local gmt = {}
    local prevenvmt = getmetatable(env)
    if prevenvmt then
        _prev_index = prevenvmt.__index
        if prevenvmt.__newindex then
            gmt.__newindex = prevenvmt.__newindex
        end
    end

    function gmt.hook(handler)
        _hook = handler
    end

    function gmt.__index(t,name)
        local found = modules[name]
        -- either true, or the name of the module containing this class.
        -- either way, we load the required module and make it globally available.
        if found then
            -- e..g pretty.dump causes pl.pretty to become available as 'pretty'
            rawset(env,name,require('pl.'..name))
            return env[name]
        else
            local res
            if _hook then
                res = _hook(t,name)
                if res then return res end
            end
            if _prev_index then
                return _prev_index(t,name)
            end
        end
    end

    if mod then
        function gmt.__newindex(t,name,value)
            mod[name] = value
            rawset(t,name,value)
        end
    end

    setmetatable(env,gmt)

    return env,mod or env
end

end,

["pl.init"] = function()
--------------------
-- Module: 'pl.init'
--------------------
--------------
-- Entry point for loading all PL libraries only on demand, into the global space.
-- Requiring 'pl' means that whenever a module is implicitly accesssed
-- (e.g. `utils.split`)
-- then that module is dynamically loaded. The submodules are all brought into
-- the global space.
--Updated to use @{pl.import_into}
-- @module pl
require'pl.import_into'(_G)

if rawget(_G,'PENLIGHT_STRICT') then require 'pl.strict' end

end,

["pl.input"] = function()
--------------------
-- Module: 'pl.input'
--------------------
--- Iterators for extracting words or numbers from an input source.
--
--    require 'pl'
--    local total,n = seq.sum(input.numbers())
--    print('average',total/n)
--
-- _source_ is defined as a string or a file-like object (i.e. has a read() method which returns the next line)
--
-- See @{06-data.md.Reading_Unstructured_Text_Data|here}
--
-- Dependencies: `pl.utils`
-- @module pl.input
local strfind = string.find
local strsub = string.sub
local strmatch = string.match
local utils = require 'pl.utils'
local unpack = utils.unpack
local pairs,type,tonumber = pairs,type,tonumber
local patterns = utils.patterns
local io = io

local input = {}

--- create an iterator over all tokens.
-- based on allwords from PiL, 7.1
-- @func getter any function that returns a line of text
-- @string pattern
-- @string[opt] fn  Optionally can pass a function to process each token as it's found.
-- @return an iterator
function input.alltokens (getter,pattern,fn)
    local line = getter()  -- current line
    local pos = 1           -- current position in the line
    return function ()      -- iterator function
        while line do         -- repeat while there are lines
          local s, e = strfind(line, pattern, pos)
          if s then           -- found a word?
            pos = e + 1       -- next position is after this token
            local res = strsub(line, s, e)     -- return the token
            if fn then res = fn(res) end
            return res
          else
            line = getter()  -- token not found; try next line
            pos = 1           -- restart from first position
          end
        end
        return nil            -- no more lines: end of traversal
   end
end
local alltokens = input.alltokens

-- question: shd this _split_ a string containing line feeds?

--- create a function which grabs the next value from a source. If the source is a string, then the getter
-- will return the string and thereafter return nil. If not specified then the source is assumed to be stdin.
-- @param f a string or a file-like object (i.e. has a read() method which returns the next line)
-- @return a getter function
function input.create_getter(f)
    if f then
        if type(f) == 'string' then
            local ls = utils.split(f,'\n')
            local i,n = 0,#ls
            return function()
                i = i + 1
                if i > n then return nil end
                return ls[i]
            end
        else
            -- anything that supports the read() method!
            if not f.read then error('not a file-like object') end
            return function() return f:read() end
        end
    else
        return io.read  -- i.e. just read from stdin
    end
end

--- generate a sequence of numbers from a source.
-- @param f A source
-- @return An iterator
function input.numbers(f)
    return alltokens(input.create_getter(f),
        '('..patterns.FLOAT..')',tonumber)
end

--- generate a sequence of words from a source.
-- @param f A source
-- @return An iterator
function input.words(f)
    return alltokens(input.create_getter(f),"%w+")
end

local function apply_tonumber (no_fail,...)
    local args = {...}
    for i = 1,#args do
        local n = tonumber(args[i])
        if  n == nil then
            if not no_fail then return nil,args[i] end
        else
            args[i] = n
        end
    end
    return args
end

--- parse an input source into fields.
-- By default, will fail if it cannot convert a field to a number.
-- @param ids a list of field indices, or a maximum field index
-- @string delim delimiter to parse fields (default space)
-- @param f a source @see create_getter
-- @tab opts option table, `{no_fail=true}`
-- @return an iterator with the field values
-- @usage for x,y in fields {2,3} do print(x,y) end -- 2nd and 3rd fields from stdin
function input.fields (ids,delim,f,opts)
  local sep
  local s
  local getter = input.create_getter(f)
  local no_fail = opts and opts.no_fail
  local no_convert = opts and opts.no_convert
  if not delim or delim == ' ' then
      delim = '%s'
      sep = '%s+'
      s = '%s*'
  else
      sep = delim
      s = ''
  end
  local max_id = 0
  if type(ids) == 'table' then
    for i,id in pairs(ids) do
      if id > max_id then max_id = id end
    end
  else
    max_id = ids
    ids = {}
    for i = 1,max_id do ids[#ids+1] = i end
  end
  local pat = '[^'..delim..']*'
  local k = 1
  for i = 1,max_id do
    if ids[k] == i then
      k = k + 1
      s = s..'('..pat..')'
    else
      s = s..pat
    end
    if i < max_id then
      s = s..sep
    end
  end
  local linecount = 1
  return function()
    local line,results,err
    repeat
        line = getter()
        linecount = linecount + 1
        if not line then return nil end
        if no_convert then
            results = {strmatch(line,s)}
        else
            results,err = apply_tonumber(no_fail,strmatch(line,s))
            if not results then
                utils.quit("line "..(linecount-1)..": cannot convert '"..err.."' to number")
            end
        end
    until #results > 0
    return unpack(results)
  end
end

return input


end,

["pl.lapp"] = function()
--------------------
-- Module: 'pl.lapp'
--------------------
--- Simple command-line parsing using human-readable specification.
-- Supports GNU-style parameters.
--
--      lapp = require 'pl.lapp'
--      local args = lapp [[
--      Does some calculations
--        -o,--offset (default 0.0)  Offset to add to scaled number
--        -s,--scale  (number)  Scaling factor
--        <number> (number) Number to be scaled
--      ]]
--
--      print(args.offset + args.scale * args.number)
--
-- Lines beginning with `'-'` are flags; there may be a short and a long name;
-- lines beginning with `'<var>'` are arguments.  Anything in parens after
-- the flag/argument is either a default, a type name or a range constraint.
--
-- See @{08-additional.md.Command_line_Programs_with_Lapp|the Guide}
--
-- Dependencies: `pl.sip`
-- @module pl.lapp

local status,sip = pcall(require,'pl.sip')
if not status then
    sip = require 'sip'
end
local match = sip.match_at_start
local append,tinsert = table.insert,table.insert

sip.custom_pattern('X','(%a[%w_%-]*)')

local function lines(s) return s:gmatch('([^\n]*)\n') end
local function lstrip(str)  return str:gsub('^%s+','')  end
local function strip(str)  return lstrip(str):gsub('%s+$','') end
local function at(s,k)  return s:sub(k,k) end

local lapp = {}

local open_files,parms,aliases,parmlist,usage,script

lapp.callback = false -- keep Strict happy

local filetypes = {
    stdin = {io.stdin,'file-in'}, stdout = {io.stdout,'file-out'},
    stderr = {io.stderr,'file-out'}
}

--- controls whether to dump usage on error.
-- Defaults to true
lapp.show_usage_error = true

--- quit this script immediately.
-- @string msg optional message
-- @bool no_usage suppress 'usage' display
function lapp.quit(msg,no_usage)
    if no_usage == 'throw' then
        error(msg)
    end
    if msg then
        io.stderr:write(msg..'\n\n')
    end
    if not no_usage then
        io.stderr:write(usage)
    end
    os.exit(1)
end

--- print an error to stderr and quit.
-- @string msg a message
-- @bool no_usage suppress 'usage' display
function lapp.error(msg,no_usage)
    if not lapp.show_usage_error then
        no_usage = true
    elseif lapp.show_usage_error == 'throw' then
        no_usage = 'throw'
    end
    lapp.quit(script..': '..msg,no_usage)
end

--- open a file.
-- This will quit on error, and keep a list of file objects for later cleanup.
-- @string file filename
-- @string[opt] opt same as second parameter of `io.open`
function lapp.open (file,opt)
    local val,err = io.open(file,opt)
    if not val then lapp.error(err,true) end
    append(open_files,val)
    return val
end

--- quit if the condition is false.
-- @bool condn a condition
-- @string msg message text
function lapp.assert(condn,msg)
    if not condn then
        lapp.error(msg)
    end
end

local function range_check(x,min,max,parm)
    lapp.assert(min <= x and max >= x,parm..' out of range')
end

local function xtonumber(s)
    local val = tonumber(s)
    if not val then lapp.error("unable to convert to number: "..s) end
    return val
end

local types = {}

local builtin_types = {string=true,number=true,['file-in']='file',['file-out']='file',boolean=true}

local function convert_parameter(ps,val)
    if ps.converter then
        val = ps.converter(val)
    end
    if ps.type == 'number' then
        val = xtonumber(val)
    elseif builtin_types[ps.type] == 'file' then
        val = lapp.open(val,(ps.type == 'file-in' and 'r') or 'w' )
    elseif ps.type == 'boolean' then
        return val
    end
    if ps.constraint then
        ps.constraint(val)
    end
    return val
end

--- add a new type to Lapp. These appear in parens after the value like
-- a range constraint, e.g. '<ival> (integer) Process PID'
-- @string name name of type
-- @param converter either a function to convert values, or a Lua type name.
-- @func[opt] constraint optional function to verify values, should use lapp.error
-- if failed.
function lapp.add_type (name,converter,constraint)
    types[name] = {converter=converter,constraint=constraint}
end

local function force_short(short)
    lapp.assert(#short==1,short..": short parameters should be one character")
end

-- deducing type of variable from default value;
local function process_default (sval,vtype)
    local val, success
    if not vtype or vtype == 'number' then
        val = tonumber(sval)
    end
    if val then -- we have a number!
        return val,'number'
    elseif filetypes[sval] then
        local ft = filetypes[sval]
        return ft[1],ft[2]
    else
        if sval == 'true' and not vtype then
            return true, 'boolean'
        end
        if sval:match '^["\']' then sval = sval:sub(2,-2) end

        local ps = types[vtype] or {}
        ps.type = vtype

        local show_usage_error = lapp.show_usage_error
        lapp.show_usage_error = "throw"
        success, val = pcall(convert_parameter, ps, sval)
        lapp.show_usage_error = show_usage_error
        if success then
          return val, vtype or 'string'
        end

        return sval,vtype or 'string'
    end
end

--- process a Lapp options string.
-- Usually called as `lapp()`.
-- @string str the options text
-- @tparam {string} args a table of arguments (default is `_G.arg`)
-- @return a table with parameter-value pairs
function lapp.process_options_string(str,args)
    local results = {}
    local varargs
    local arg = args or _G.arg
    open_files = {}
    parms = {}
    aliases = {}
    parmlist = {}

    local function check_varargs(s)
        local res,cnt = s:gsub('^%.%.%.%s*','')
        return res, (cnt > 0)
    end

    local function set_result(ps,parm,val)
        parm = type(parm) == "string" and parm:gsub("%W", "_") or parm -- so foo-bar becomes foo_bar in Lua
        if not ps.varargs then
            results[parm] = val
        else
            if not results[parm] then
                results[parm] = { val }
            else
                append(results[parm],val)
            end
        end
    end

    usage = str

    for _,a in ipairs(arg) do
      if a == "-h" or a == "--help" then
        return lapp.quit()
      end
    end


    for line in lines(str) do
        local res = {}
        local optparm,defval,vtype,constraint,rest
        line = lstrip(line)
        local function check(str)
            return match(str,line,res)
        end

        -- flags: either '-<short>', '-<short>,--<long>' or '--<long>'
        if check '-$v{short}, --$o{long} $' or check '-$v{short} $' or check '--$o{long} $' then
            if res.long then
                optparm = res.long:gsub('[^%w%-]','_')  -- I'm not sure the $o pattern will let anything else through?
                if #res.rest == 1 then optparm = optparm .. res.rest end
                if res.short then aliases[res.short] = optparm  end
            else
                optparm = res.short
            end
            if res.short and not lapp.slack then force_short(res.short) end
            res.rest, varargs = check_varargs(res.rest)
        elseif check '$<{name} $'  then -- is it <parameter_name>?
            -- so <input file...> becomes input_file ...
            optparm,rest = res.name:match '([^%.]+)(.*)'
            optparm = optparm:gsub('%A','_')
            varargs = rest == '...'
            append(parmlist,optparm)
        end
        -- this is not a pure doc line and specifies the flag/parameter type
        if res.rest then
            line = res.rest
            res = {}
            local optional
            -- do we have ([optional] [<type>] [default <val>])?
            if match('$({def} $',line,res) or match('$({def}',line,res) then
                local typespec = strip(res.def)
                local ftype, rest = typespec:match('^(%S+)(.*)$')
                rest = strip(rest)
                if ftype == 'optional' then
                    ftype, rest = rest:match('^(%S+)(.*)$')
                    rest = strip(rest)
                    optional = true
                end
                local default
                if ftype == 'default' then
                    default = true
                    if rest == '' then lapp.error("value must follow default") end
                else -- a type specification
                    if match('$f{min}..$f{max}',ftype,res) then
                        -- a numerical range like 1..10
                        local min,max = res.min,res.max
                        vtype = 'number'
                        constraint = function(x)
                            range_check(x,min,max,optparm)
                        end
                    elseif not ftype:match '|' then -- plain type
                        vtype = ftype
                    else
                        -- 'enum' type is a string which must belong to
                        -- one of several distinct values
                        local enums = ftype
                        local enump = '|' .. enums .. '|'
                        vtype = 'string'
                        constraint = function(s)
                            lapp.assert(enump:find('|'..s..'|', 1, true),
                              "value '"..s.."' not in "..enums
                            )
                        end
                    end
                end
                res.rest = rest
                typespec = res.rest
                -- optional 'default value' clause. Type is inferred as
                -- 'string' or 'number' if there's no explicit type
                if default or match('default $r{rest}',typespec,res) then
                    defval,vtype = process_default(res.rest,vtype)
                end
            else -- must be a plain flag, no extra parameter required
                defval = false
                vtype = 'boolean'
            end
            local ps = {
                type = vtype,
                defval = defval,
                required = defval == nil and not optional,
                comment = res.rest or optparm,
                constraint = constraint,
                varargs = varargs
            }
            varargs = nil
            if types[vtype] then
                local converter = types[vtype].converter
                if type(converter) == 'string' then
                    ps.type = converter
                else
                    ps.converter = converter
                end
                ps.constraint = types[vtype].constraint
            elseif not builtin_types[vtype] and vtype then
                lapp.error(vtype.." is unknown type")
            end
            parms[optparm] = ps
        end
    end
    -- cool, we have our parms, let's parse the command line args
    local iparm = 1
    local iextra = 1
    local i = 1
    local parm,ps,val
    local end_of_flags = false

    local function check_parm (parm)
        local eqi = parm:find '[=:]'
        if eqi then
            tinsert(arg,i+1,parm:sub(eqi+1))
            parm = parm:sub(1,eqi-1)
        end
        return parm,eqi
    end

    local function is_flag (parm)
        return parms[aliases[parm] or parm]
    end

    while i <= #arg do
        local theArg = arg[i]
        local res = {}
        -- after '--' we don't parse args and they end up in
        -- the array part of the result (args[1] etc)
        if theArg == '--' then
            end_of_flags = true
            iparm = #parmlist + 1
            i = i + 1
            theArg = arg[i]
            if not theArg then
                break
            end
        end
        -- look for a flag, -<short flags> or --<long flag>
        if not end_of_flags and (match('--$S{long}',theArg,res) or match('-$S{short}',theArg,res)) then
            if res.long then -- long option
                parm = check_parm(res.long)
            elseif #res.short == 1 or is_flag(res.short) then
                parm = res.short
            else
                local parmstr,eq = check_parm(res.short)
                if not eq then
                    parm = at(parmstr,1)
                    local flag = is_flag(parm)
                    if flag and flag.type ~= 'boolean' then
                    --if isdigit(at(parmstr,2)) then
                        -- a short option followed by a digit is an exception (for AW;))
                        -- push ahead into the arg array
                        tinsert(arg,i+1,parmstr:sub(2))
                    else
                        -- push multiple flags into the arg array!
                        for k = 2,#parmstr do
                            tinsert(arg,i+k-1,'-'..at(parmstr,k))
                        end
                    end
                else
                    parm = parmstr
                end
            end
            if aliases[parm] then parm = aliases[parm] end
            if not parms[parm] and (parm == 'h' or parm == 'help') then
                lapp.quit()
            end
        else -- a parameter
            parm = parmlist[iparm]
            if not parm then
               -- extra unnamed parameters are indexed starting at 1
               parm = iextra
               ps = { type = 'string' }
               parms[parm] = ps
               iextra = iextra + 1
            else
                ps = parms[parm]
            end
            if not ps.varargs then
                iparm = iparm + 1
            end
            val = theArg
        end
        ps = parms[parm]
        if not ps then lapp.error("unrecognized parameter: "..parm) end
        if ps.type ~= 'boolean' then -- we need a value! This should follow
            if not val then
                i = i + 1
                val = arg[i]
                theArg = val
            end
            lapp.assert(val,parm.." was expecting a value")
        else -- toggle boolean flags (usually false -> true)
            val = not ps.defval
        end
        ps.used = true
        val = convert_parameter(ps,val)
        set_result(ps,parm,val)
        if builtin_types[ps.type] == 'file' then
            set_result(ps,parm..'_name',theArg)
        end
        if lapp.callback then
            lapp.callback(parm,theArg,res)
        end
        i = i + 1
        val = nil
    end
    -- check unused parms, set defaults and check if any required parameters were missed
    for parm,ps in pairs(parms) do
        if not ps.used then
            if ps.required then lapp.error("missing required parameter: "..parm) end
            set_result(ps,parm,ps.defval)
        end
    end
    return results
end

if arg then
    script = arg[0]
    script = script or rawget(_G,"LAPP_SCRIPT") or "unknown"
    -- strip dir and extension to get current script name
    script = script:gsub('.+[\\/]',''):gsub('%.%a+$','')
else
    script = "inter"
end


setmetatable(lapp, {
    __call = function(tbl,str,args) return lapp.process_options_string(str,args) end,
})


return lapp



end,

["pl.lexer"] = function()
--------------------
-- Module: 'pl.lexer'
--------------------
--- Lexical scanner for creating a sequence of tokens from text.
-- `lexer.scan(s)` returns an iterator over all tokens found in the
-- string `s`. This iterator returns two values, a token type string
-- (such as 'string' for quoted string, 'iden' for identifier) and the value of the
-- token.
--
-- Versions specialized for Lua and C are available; these also handle block comments
-- and classify keywords as 'keyword' tokens. For example:
--
--    > s = 'for i=1,n do'
--    > for t,v in lexer.lua(s)  do print(t,v) end
--    keyword for
--    iden    i
--    =       =
--    number  1
--    ,       ,
--    iden    n
--    keyword do
--
-- See the Guide for further @{06-data.md.Lexical_Scanning|discussion}
-- @module pl.lexer

local strfind = string.find
local strsub = string.sub
local append = table.insert


local function assert_arg(idx,val,tp)
    if type(val) ~= tp then
        error("argument "..idx.." must be "..tp, 2)
    end
end

local lexer = {}

local NUMBER1  = '^[%+%-]?%d+%.?%d*[eE][%+%-]?%d+'
local NUMBER1a = '^[%+%-]?%d*%.%d+[eE][%+%-]?%d+'
local NUMBER2  = '^[%+%-]?%d+%.?%d*'
local NUMBER2a = '^[%+%-]?%d*%.%d+'
local NUMBER3  = '^0x[%da-fA-F]+'
local NUMBER4  = '^%d+%.?%d*[eE][%+%-]?%d+'
local NUMBER4a = '^%d*%.%d+[eE][%+%-]?%d+'
local NUMBER5  = '^%d+%.?%d*'
local NUMBER5a = '^%d*%.%d+'
local IDEN = '^[%a_][%w_]*'
local WSPACE = '^%s+'
local STRING1 = "^(['\"])%1" -- empty string
local STRING2 = [[^(['"])(\*)%2%1]]
local STRING3 = [[^(['"]).-[^\](\*)%2%1]]
local CHAR1 = "^''"
local CHAR2 = [[^'(\*)%1']]
local CHAR3 = [[^'.-[^\](\*)%1']]
local PREPRO = '^#.-[^\\]\n'

local plain_matches,lua_matches,cpp_matches,lua_keyword,cpp_keyword

local function tdump(tok)
    return tok,tok
end

local function ndump(tok,options)
    if options and options.number then
        tok = tonumber(tok)
    end
    return "number",tok
end

-- regular strings, single or double quotes; usually we want them
-- without the quotes
local function sdump(tok,options)
    if options and options.string then
        tok = tok:sub(2,-2)
    end
    return "string",tok
end

-- long Lua strings need extra work to get rid of the quotes
local function sdump_l(tok,options,findres)
    if options and options.string then
        local quotelen = 3
        if findres[3] then
            quotelen = quotelen + findres[3]:len()
        end
        tok = tok:sub(quotelen, -quotelen)
        if tok:sub(1, 1) == "\n" then
            tok = tok:sub(2)
        end
    end
    return "string",tok
end

local function chdump(tok,options)
    if options and options.string then
        tok = tok:sub(2,-2)
    end
    return "char",tok
end

local function cdump(tok)
    return "comment",tok
end

local function wsdump (tok)
    return "space",tok
end

local function pdump (tok)
    return "prepro",tok
end

local function plain_vdump(tok)
    return "iden",tok
end

local function lua_vdump(tok)
    if lua_keyword[tok] then
        return "keyword",tok
    else
        return "iden",tok
    end
end

local function cpp_vdump(tok)
    if cpp_keyword[tok] then
        return "keyword",tok
    else
        return "iden",tok
    end
end

--- create a plain token iterator from a string or file-like object.
-- @tparam string|file s a string or a file-like object with `:read()` method returning lines.
-- @tab matches an optional match table - array of token descriptions.
-- A token is described by a `{pattern, action}` pair, where `pattern` should match
-- token body and `action` is a function called when a token of described type is found.
-- @tab[opt] filter a table of token types to exclude, by default `{space=true}`
-- @tab[opt] options a table of options; by default, `{number=true,string=true}`,
-- which means convert numbers and strip string quotes.
function lexer.scan(s,matches,filter,options)
    local file = type(s) ~= 'string' and s
    filter = filter or {space=true}
    options = options or {number=true,string=true}
    if filter then
        if filter.space then filter[wsdump] = true end
        if filter.comments then
            filter[cdump] = true
        end
    end
    if not matches then
        if not plain_matches then
            plain_matches = {
                {WSPACE,wsdump},
                {NUMBER3,ndump},
                {IDEN,plain_vdump},
                {NUMBER1,ndump},
                {NUMBER1a,ndump},
                {NUMBER2,ndump},
                {NUMBER2a,ndump},
                {STRING1,sdump},
                {STRING2,sdump},
                {STRING3,sdump},
                {'^.',tdump}
            }
        end
        matches = plain_matches
    end

    local line_nr = 0
    local next_line = file and file:read()
    local sz = file and 0 or #s
    local idx = 1

    local tlist_i
    local tlist

    local first_hit = true

    local function iter(res)
        local tp = type(res)

        if tlist then -- returning the inserted token list
            local cur = tlist[tlist_i]
            if cur then
                tlist_i = tlist_i + 1
                return cur[1], cur[2]
            else
                tlist = nil
            end
        end

        if tp == 'string' then -- search up to some special pattern
            local i1,i2 = strfind(s,res,idx)
            if i1 then
                local tok = strsub(s,i1,i2)
                idx = i2 + 1
                return '', tok
            else
                idx = sz + 1
                return '', ''
            end

        elseif tp == 'table' then -- insert a token list
            tlist_i = 1
            tlist = res
            return '', ''

        elseif tp ~= 'nil' then -- return position
            return line_nr, idx

        else -- look for next token
            if first_hit then
                if not file then line_nr = 1 end
                first_hit = false
            end

            if idx > sz then
                if file then
                    if not next_line then
                      return -- past the end of file, done
                    end
                    s = next_line
                    line_nr = line_nr + 1
                    next_line = file:read()
                    if next_line then
                        s = s .. '\n'
                    end
                    idx, sz = 1, #s
                else
                    return -- past the end of input, done
                end
            end

            for _,m in ipairs(matches) do
                local pat = m[1]
                local fun = m[2]
                local findres = {strfind(s,pat,idx)}
                local i1, i2 = findres[1], findres[2]
                if i1 then
                    local tok = strsub(s,i1,i2)
                    idx = i2 + 1
                    local ret1, ret2
                    if not (filter and filter[fun]) then
                        lexer.finished = idx > sz
                        ret1, ret2 = fun(tok, options, findres)
                    end
                    if not file and tok:find("\n") then
                        -- Update line number.
                        local _, newlines = tok:gsub("\n", {})
                        line_nr = line_nr + newlines
                    end
                    if ret1 then
                        return ret1, ret2 -- found a match
                    else
                        return iter() -- tail-call to try again
                    end
                end
            end
        end
    end

    return iter
end

local function isstring (s)
    return type(s) == 'string'
end

--- insert tokens into a stream.
-- @param tok a token stream
-- @param a1 a string is the type, a table is a token list and
-- a function is assumed to be a token-like iterator (returns type & value)
-- @string a2 a string is the value
function lexer.insert (tok,a1,a2)
    if not a1 then return end
    local ts
    if isstring(a1) and isstring(a2) then
        ts = {{a1,a2}}
    elseif type(a1) == 'function' then
        ts = {}
        for t,v in a1() do
            append(ts,{t,v})
        end
    else
        ts = a1
    end
    tok(ts)
end

--- get everything in a stream upto a newline.
-- @param tok a token stream
-- @return a string
function lexer.getline (tok)
    local _,v = tok('.-\n')
    return v
end

--- get current line number.
-- @param tok a token stream
-- @return the line number.
-- if the input source is a file-like object,
-- also return the column.
function lexer.lineno (tok)
    return tok(0)
end

--- get the rest of the stream.
-- @param tok a token stream
-- @return a string
function lexer.getrest (tok)
    local _,v = tok('.+')
    return v
end

--- get the Lua keywords as a set-like table.
-- So `res["and"]` etc would be `true`.
-- @return a table
function lexer.get_keywords ()
    if not lua_keyword then
        lua_keyword = {
            ["and"] = true, ["break"] = true,  ["do"] = true,
            ["else"] = true, ["elseif"] = true, ["end"] = true,
            ["false"] = true, ["for"] = true, ["function"] = true,
            ["if"] = true, ["in"] = true,  ["local"] = true, ["nil"] = true,
            ["not"] = true, ["or"] = true, ["repeat"] = true,
            ["return"] = true, ["then"] = true, ["true"] = true,
            ["until"] = true,  ["while"] = true
        }
    end
    return lua_keyword
end

--- create a Lua token iterator from a string or file-like object.
-- Will return the token type and value.
-- @string s the string
-- @tab[opt] filter a table of token types to exclude, by default `{space=true,comments=true}`
-- @tab[opt] options a table of options; by default, `{number=true,string=true}`,
-- which means convert numbers and strip string quotes.
function lexer.lua(s,filter,options)
    filter = filter or {space=true,comments=true}
    lexer.get_keywords()
    if not lua_matches then
        lua_matches = {
            {WSPACE,wsdump},
            {NUMBER3,ndump},
            {IDEN,lua_vdump},
            {NUMBER4,ndump},
            {NUMBER4a,ndump},
            {NUMBER5,ndump},
            {NUMBER5a,ndump},
            {STRING1,sdump},
            {STRING2,sdump},
            {STRING3,sdump},
            {'^%-%-%[(=*)%[.-%]%1%]',cdump},
            {'^%-%-.-\n',cdump},
            {'^%[(=*)%[.-%]%1%]',sdump_l},
            {'^==',tdump},
            {'^~=',tdump},
            {'^<=',tdump},
            {'^>=',tdump},
            {'^%.%.%.',tdump},
            {'^%.%.',tdump},
            {'^.',tdump}
        }
    end
    return lexer.scan(s,lua_matches,filter,options)
end

--- create a C/C++ token iterator from a string or file-like object.
-- Will return the token type type and value.
-- @string s the string
-- @tab[opt] filter a table of token types to exclude, by default `{space=true,comments=true}`
-- @tab[opt] options a table of options; by default, `{number=true,string=true}`,
-- which means convert numbers and strip string quotes.
function lexer.cpp(s,filter,options)
    filter = filter or {space=true,comments=true}
    if not cpp_keyword then
        cpp_keyword = {
            ["class"] = true, ["break"] = true,  ["do"] = true, ["sizeof"] = true,
            ["else"] = true, ["continue"] = true, ["struct"] = true,
            ["false"] = true, ["for"] = true, ["public"] = true, ["void"] = true,
            ["private"] = true, ["protected"] = true, ["goto"] = true,
            ["if"] = true, ["static"] = true,  ["const"] = true, ["typedef"] = true,
            ["enum"] = true, ["char"] = true, ["int"] = true, ["bool"] = true,
            ["long"] = true, ["float"] = true, ["true"] = true, ["delete"] = true,
            ["double"] = true,  ["while"] = true, ["new"] = true,
            ["namespace"] = true, ["try"] = true, ["catch"] = true,
            ["switch"] = true, ["case"] = true, ["extern"] = true,
            ["return"] = true,["default"] = true,['unsigned']  = true,['signed'] = true,
            ["union"] =  true, ["volatile"] = true, ["register"] = true,["short"] = true,
        }
    end
    if not cpp_matches then
        cpp_matches = {
            {WSPACE,wsdump},
            {PREPRO,pdump},
            {NUMBER3,ndump},
            {IDEN,cpp_vdump},
            {NUMBER4,ndump},
            {NUMBER4a,ndump},
            {NUMBER5,ndump},
            {NUMBER5a,ndump},
            {CHAR1,chdump},
            {CHAR2,chdump},
            {CHAR3,chdump},
            {STRING1,sdump},
            {STRING2,sdump},
            {STRING3,sdump},
            {'^//.-\n',cdump},
            {'^/%*.-%*/',cdump},
            {'^==',tdump},
            {'^!=',tdump},
            {'^<=',tdump},
            {'^>=',tdump},
            {'^->',tdump},
            {'^&&',tdump},
            {'^||',tdump},
            {'^%+%+',tdump},
            {'^%-%-',tdump},
            {'^%+=',tdump},
            {'^%-=',tdump},
            {'^%*=',tdump},
            {'^/=',tdump},
            {'^|=',tdump},
            {'^%^=',tdump},
            {'^::',tdump},
            {'^.',tdump}
        }
    end
    return lexer.scan(s,cpp_matches,filter,options)
end

--- get a list of parameters separated by a delimiter from a stream.
-- @param tok the token stream
-- @string[opt=')'] endtoken end of list. Can be '\n'
-- @string[opt=','] delim separator
-- @return a list of token lists.
function lexer.get_separated_list(tok,endtoken,delim)
    endtoken = endtoken or ')'
    delim = delim or ','
    local parm_values = {}
    local level = 1 -- used to count ( and )
    local tl = {}
    local function tappend (tl,t,val)
        val = val or t
        append(tl,{t,val})
    end
    local is_end
    if endtoken == '\n' then
        is_end = function(t,val)
            return t == 'space' and val:find '\n'
        end
    else
        is_end = function (t)
            return t == endtoken
        end
    end
    local token,value
    while true do
        token,value=tok()
        if not token then return nil,'EOS' end -- end of stream is an error!
        if is_end(token,value) and level == 1 then
            append(parm_values,tl)
            break
        elseif token == '(' then
            level = level + 1
            tappend(tl,'(')
        elseif token == ')' then
            level = level - 1
            if level == 0 then -- finished with parm list
                append(parm_values,tl)
                break
            else
                tappend(tl,')')
            end
        elseif token == delim and level == 1 then
            append(parm_values,tl) -- a new parm
            tl = {}
        else
            tappend(tl,token,value)
        end
    end
    return parm_values,{token,value}
end

--- get the next non-space token from the stream.
-- @param tok the token stream.
function lexer.skipws (tok)
    local t,v = tok()
    while t == 'space' do
        t,v = tok()
    end
    return t,v
end

local skipws = lexer.skipws

--- get the next token, which must be of the expected type.
-- Throws an error if this type does not match!
-- @param tok the token stream
-- @string expected_type the token type
-- @bool no_skip_ws whether we should skip whitespace
function lexer.expecting (tok,expected_type,no_skip_ws)
    assert_arg(1,tok,'function')
    assert_arg(2,expected_type,'string')
    local t,v
    if no_skip_ws then
        t,v = tok()
    else
        t,v = skipws(tok)
    end
    if t ~= expected_type then error ("expecting "..expected_type,2) end
    return v
end

return lexer

end,

["pl.List"] = function()
--------------------
-- Module: 'pl.List'
--------------------
--- Python-style list class.
--
-- **Please Note**: methods that change the list will return the list.
-- This is to allow for method chaining, but please note that `ls = ls:sort()`
-- does not mean that a new copy of the list is made. In-place (mutable) methods
-- are marked as returning 'the list' in this documentation.
--
-- See the Guide for further @{02-arrays.md.Python_style_Lists|discussion}
--
-- See <a href="http://www.python.org/doc/current/tut/tut.html">http://www.python.org/doc/current/tut/tut.html</a>, section 5.1
--
-- **Note**: The comments before some of the functions are from the Python docs
-- and contain Python code.
--
-- Written for Lua version Nick Trout 4.0; Redone for Lua 5.1, Steve Donovan.
--
-- Dependencies: `pl.utils`, `pl.tablex`, `pl.class`
-- @classmod pl.List
-- @pragma nostrip

local tinsert,tremove,concat,tsort = table.insert,table.remove,table.concat,table.sort
local setmetatable, getmetatable,type,tostring,string = setmetatable,getmetatable,type,tostring,string
local tablex = require 'pl.tablex'
local filter,imap,imap2,reduce,transform,tremovevalues = tablex.filter,tablex.imap,tablex.imap2,tablex.reduce,tablex.transform,tablex.removevalues
local tsub = tablex.sub
local utils = require 'pl.utils'
local class = require 'pl.class'

local array_tostring,split,assert_arg,function_arg = utils.array_tostring,utils.split,utils.assert_arg,utils.function_arg
local normalize_slice = tablex._normalize_slice

-- metatable for our list and map objects has already been defined..
local Multimap = utils.stdmt.MultiMap
local List = utils.stdmt.List

local iter

class(nil,nil,List)

-- we want the result to be _covariant_, i.e. t must have type of obj if possible
local function makelist (t,obj)
    local klass = List
    if obj then
        klass = getmetatable(obj)
    end
    return setmetatable(t,klass)
end

local function simple_table(t)
    return type(t) == 'table' and not getmetatable(t) and #t > 0
end

function List._create (src)
    if simple_table(src) then return src end
end

function List:_init (src)
    if self == src then return end -- existing table used as self!
    if src then
        for v in iter(src) do
            tinsert(self,v)
        end
    end
end

--- Create a new list. Can optionally pass a table;
-- passing another instance of List will cause a copy to be created;
-- this will return a plain table with an appropriate metatable.
-- we pass anything which isn't a simple table to iterate() to work out
-- an appropriate iterator
-- @see List.iterate
-- @param[opt] t An optional list-like table
-- @return a new List
-- @usage ls = List();  ls = List {1,2,3,4}
-- @function List.new

List.new = List

--- Make a copy of an existing list.
-- The difference from a plain 'copy constructor' is that this returns
-- the actual List subtype.
function List:clone()
    local ls = makelist({},self)
    ls:extend(self)
    return ls
end

--- Add an item to the end of the list.
-- @param i An item
-- @return the list
function List:append(i)
    tinsert(self,i)
    return self
end

List.push = tinsert

--- Extend the list by appending all the items in the given list.
-- equivalent to 'a[len(a):] = L'.
-- @tparam List L Another List
-- @return the list
function List:extend(L)
    assert_arg(1,L,'table')
    for i = 1,#L do tinsert(self,L[i]) end
    return self
end

--- Insert an item at a given position. i is the index of the
-- element before which to insert.
-- @int i index of element before whichh to insert
-- @param x A data item
-- @return the list
function List:insert(i, x)
    assert_arg(1,i,'number')
    tinsert(self,i,x)
    return self
end

--- Insert an item at the begining of the list.
-- @param x a data item
-- @return the list
function List:put (x)
    return self:insert(1,x)
end

--- Remove an element given its index.
-- (equivalent of Python's del s[i])
-- @int i the index
-- @return the list
function List:remove (i)
    assert_arg(1,i,'number')
    tremove(self,i)
    return self
end

--- Remove the first item from the list whose value is given.
-- (This is called 'remove' in Python; renamed to avoid confusion
-- with table.remove)
-- Return nil if there is no such item.
-- @param x A data value
-- @return the list
function List:remove_value(x)
    for i=1,#self do
        if self[i]==x then tremove(self,i) return self end
    end
    return self
 end

--- Remove the item at the given position in the list, and return it.
-- If no index is specified, a:pop() returns the last item in the list.
-- The item is also removed from the list.
-- @int[opt] i An index
-- @return the item
function List:pop(i)
    if not i then i = #self end
    assert_arg(1,i,'number')
    return tremove(self,i)
end

List.get = List.pop

--- Return the index in the list of the first item whose value is given.
-- Return nil if there is no such item.
-- @function List:index
-- @param x A data value
-- @int[opt=1] idx where to start search
-- @return the index, or nil if not found.

local tfind = tablex.find
List.index = tfind

--- Does this list contain the value?
-- @param x A data value
-- @return true or false
function List:contains(x)
    return tfind(self,x) and true or false
end

--- Return the number of times value appears in the list.
-- @param x A data value
-- @return number of times x appears
function List:count(x)
    local cnt=0
    for i=1,#self do
        if self[i]==x then cnt=cnt+1 end
    end
    return cnt
end

--- Sort the items of the list, in place.
-- @func[opt='<'] cmp an optional comparison function
-- @return the list
function List:sort(cmp)
    if cmp then cmp = function_arg(1,cmp) end
    tsort(self,cmp)
    return self
end

--- Return a sorted copy of this list.
-- @func[opt='<'] cmp an optional comparison function
-- @return a new list
function List:sorted(cmp)
    return List(self):sort(cmp)
end

--- Reverse the elements of the list, in place.
-- @return the list
function List:reverse()
    local t = self
    local n = #t
    for i = 1,n/2 do
        t[i],t[n] = t[n],t[i]
        n = n - 1
    end
    return self
end

--- Return the minimum and the maximum value of the list.
-- @return minimum value
-- @return maximum value
function List:minmax()
    local vmin,vmax = 1e70,-1e70
    for i = 1,#self do
        local v = self[i]
        if v < vmin then vmin = v end
        if v > vmax then vmax = v end
    end
    return vmin,vmax
end

--- Emulate list slicing.  like  'list[first:last]' in Python.
-- If first or last are negative then they are relative to the end of the list
-- eg. slice(-2) gives last 2 entries in a list, and
-- slice(-4,-2) gives from -4th to -2nd
-- @param first An index
-- @param last An index
-- @return a new List
function List:slice(first,last)
    return tsub(self,first,last)
end

--- Empty the list.
-- @return the list
function List:clear()
    for i=1,#self do tremove(self) end
    return self
end

local eps = 1.0e-10

--- Emulate Python's range(x) function.
-- Include it in List table for tidiness
-- @int start A number
-- @int[opt] finish A number greater than start; if absent,
-- then start is 1 and finish is start
-- @int[opt=1] incr an increment (may be less than 1)
-- @return a List from start .. finish
-- @usage List.range(0,3) == List{0,1,2,3}
-- @usage List.range(4) = List{1,2,3,4}
-- @usage List.range(5,1,-1) == List{5,4,3,2,1}
function List.range(start,finish,incr)
    if not finish then
        finish = start
        start = 1
    end
    if incr then
    assert_arg(3,incr,'number')
    if math.ceil(incr) ~= incr then finish = finish + eps end
    else
        incr = 1
    end
    assert_arg(1,start,'number')
    assert_arg(2,finish,'number')
    local t = List()
    for i=start,finish,incr do tinsert(t,i) end
    return t
end

--- list:len() is the same as #list.
function List:len()
    return #self
end

-- Extended operations --

--- Remove a subrange of elements.
-- equivalent to 'del s[i1:i2]' in Python.
-- @int i1 start of range
-- @int i2 end of range
-- @return the list
function List:chop(i1,i2)
    return tremovevalues(self,i1,i2)
end

--- Insert a sublist into a list
-- equivalent to 's[idx:idx] = list' in Python
-- @int idx index
-- @tparam List list list to insert
-- @return the list
-- @usage  l = List{10,20}; l:splice(2,{21,22});  assert(l == List{10,21,22,20})
function List:splice(idx,list)
    assert_arg(1,idx,'number')
    idx = idx - 1
    local i = 1
    for v in iter(list) do
        tinsert(self,i+idx,v)
        i = i + 1
    end
    return self
end

--- General slice assignment s[i1:i2] = seq.
-- @int i1  start index
-- @int i2  end index
-- @tparam List seq a list
-- @return the list
function List:slice_assign(i1,i2,seq)
    assert_arg(1,i1,'number')
    assert_arg(1,i2,'number')
    i1,i2 = normalize_slice(self,i1,i2)
    if i2 >= i1 then self:chop(i1,i2) end
    self:splice(i1,seq)
    return self
end

--- Concatenation operator.
-- @within metamethods
-- @tparam List L another List
-- @return a new list consisting of the list with the elements of the new list appended
function List:__concat(L)
    assert_arg(1,L,'table')
    local ls = self:clone()
    ls:extend(L)
    return ls
end

--- Equality operator ==.  True iff all elements of two lists are equal.
-- @within metamethods
-- @tparam List L another List
-- @return true or false
function List:__eq(L)
    if #self ~= #L then return false end
    for i = 1,#self do
        if self[i] ~= L[i] then return false end
    end
    return true
end

--- Join the elements of a list using a delimiter.
-- This method uses tostring on all elements.
-- @string[opt=''] delim a delimiter string, can be empty.
-- @return a string
function List:join (delim)
    delim = delim or ''
    assert_arg(1,delim,'string')
    return concat(array_tostring(self),delim)
end

--- Join a list of strings. <br>
-- Uses `table.concat` directly.
-- @function List:concat
-- @string[opt=''] delim a delimiter
-- @return a string
List.concat = concat

local function tostring_q(val)
    local s = tostring(val)
    if type(val) == 'string' then
        s = '"'..s..'"'
    end
    return s
end

--- How our list should be rendered as a string. Uses join().
-- @within metamethods
-- @see List:join
function List:__tostring()
    return '{'..self:join(',',tostring_q)..'}'
end

--- Call the function on each element of the list.
-- @func fun a function or callable object
-- @param ... optional values to pass to function
function List:foreach (fun,...)
    fun = function_arg(1,fun)
    for i = 1,#self do
        fun(self[i],...)
    end
end

local function lookup_fun (obj,name)
    local f = obj[name]
    if not f then error(type(obj).." does not have method "..name,3) end
    return f
end

--- Call the named method on each element of the list.
-- @string name the method name
-- @param ... optional values to pass to function
function List:foreachm (name,...)
    for i = 1,#self do
        local obj = self[i]
        local f = lookup_fun(obj,name)
        f(obj,...)
    end
end

--- Create a list of all elements which match a function.
-- @func fun a boolean function
-- @param[opt] arg optional argument to be passed as second argument of the predicate
-- @return a new filtered list.
function List:filter (fun,arg)
    return makelist(filter(self,fun,arg),self)
end

--- Split a string using a delimiter.
-- @string s the string
-- @string[opt] delim the delimiter (default spaces)
-- @return a List of strings
-- @see pl.utils.split
function List.split (s,delim)
    assert_arg(1,s,'string')
    return makelist(split(s,delim))
end

--- Apply a function to all elements.
-- Any extra arguments will be passed to the function.
-- @func fun a function of at least one argument
-- @param ... arbitrary extra arguments.
-- @return a new list: {f(x) for x in self}
-- @usage List{'one','two'}:map(string.upper) == {'ONE','TWO'}
-- @see pl.tablex.imap
function List:map (fun,...)
    return makelist(imap(fun,self,...),self)
end

--- Apply a function to all elements, in-place.
-- Any extra arguments are passed to the function.
-- @func fun A function that takes at least one argument
-- @param ... arbitrary extra arguments.
-- @return the list.
function List:transform (fun,...)
    transform(fun,self,...)
    return self
end

--- Apply a function to elements of two lists.
-- Any extra arguments will be passed to the function
-- @func fun a function of at least two arguments
-- @tparam List ls another list
-- @param ... arbitrary extra arguments.
-- @return a new list: {f(x,y) for x in self, for x in arg1}
-- @see pl.tablex.imap2
function List:map2 (fun,ls,...)
    return makelist(imap2(fun,self,ls,...),self)
end

--- apply a named method to all elements.
-- Any extra arguments will be passed to the method.
-- @string name name of method
-- @param ... extra arguments
-- @return a new list of the results
-- @see pl.seq.mapmethod
function List:mapm (name,...)
    local res = {}
    for i = 1,#self do
      local val = self[i]
      local fn = lookup_fun(val,name)
      res[i] = fn(val,...)
    end
    return makelist(res,self)
end

local function composite_call (method,f)
    return function(self,...)
        return self[method](self,f,...)
    end
end

function List.default_map_with(T)
    return function(self,name)
        local m
        if T then
            local f = lookup_fun(T,name)
            m = composite_call('map',f)
        else
            m = composite_call('mapn',name)
        end
        getmetatable(self)[name] = m -- and cache..
        return m
    end
end

List.default_map = List.default_map_with

--- 'reduce' a list using a binary function.
-- @func fun a function of two arguments
-- @return result of the function
-- @see pl.tablex.reduce
function List:reduce (fun)
    return reduce(fun,self)
end

--- Partition a list using a classifier function.
-- The function may return nil, but this will be converted to the string key '<nil>'.
-- @func fun a function of at least one argument
-- @param ... will also be passed to the function
-- @treturn MultiMap a table where the keys are the returned values, and the values are Lists
-- of values where the function returned that key.
-- @see pl.MultiMap
function List:partition (fun,...)
    fun = function_arg(1,fun)
    local res = {}
    for i = 1,#self do
        local val = self[i]
        local klass = fun(val,...)
        if klass == nil then klass = '<nil>' end
        if not res[klass] then res[klass] = List() end
        res[klass]:append(val)
    end
    return setmetatable(res,Multimap)
end

--- return an iterator over all values.
function List:iter ()
    return iter(self)
end

--- Create an iterator over a seqence.
-- This captures the Python concept of 'sequence'.
-- For tables, iterates over all values with integer indices.
-- @param seq a sequence; a string (over characters), a table, a file object (over lines) or an iterator function
-- @usage for x in iterate {1,10,22,55} do io.write(x,',') end ==> 1,10,22,55
-- @usage for ch in iterate 'help' do do io.write(ch,' ') end ==> h e l p
function List.iterate(seq)
    if type(seq) == 'string' then
        local idx = 0
        local n = #seq
        local sub = string.sub
        return function ()
            idx = idx + 1
            if idx > n then return nil
            else
                return sub(seq,idx,idx)
            end
        end
    elseif type(seq) == 'table' then
        local idx = 0
        local n = #seq
        return function()
            idx = idx + 1
            if idx > n then return nil
            else
                return seq[idx]
            end
        end
    elseif type(seq) == 'function' then
        return seq
    elseif type(seq) == 'userdata' and io.type(seq) == 'file' then
        return seq:lines()
    end
end
iter = List.iterate

return List


end,

["pl.luabalanced"] = function()
--------------------
-- Module: 'pl.luabalanced'
--------------------
--- Extract delimited Lua sequences from strings.
-- Inspired by Damian Conway's Text::Balanced in Perl. <br/>
-- <ul>
--   <li>[1] <a href="http://lua-users.org/wiki/LuaBalanced">Lua Wiki Page</a></li>
--   <li>[2] http://search.cpan.org/dist/Text-Balanced/lib/Text/Balanced.pm</li>
-- </ul> <br/>
-- <pre class=example>
-- local lb = require "pl.luabalanced"
-- --Extract Lua expression starting at position 4.
--  print(lb.match_expression("if x^2 + x > 5 then print(x) end", 4))
--  --> x^2 + x > 5     16
-- --Extract Lua string starting at (default) position 1.
-- print(lb.match_string([["test\"123" .. "more"]]))
-- --> "test\"123"     12
-- </pre>
-- (c) 2008, David Manura, Licensed under the same terms as Lua (MIT license).
-- @class module
-- @name pl.luabalanced

local M = {}

local assert = assert

-- map opening brace <-> closing brace.
local ends = { ['('] = ')', ['{'] = '}', ['['] = ']' }
local begins = {}; for k,v in pairs(ends) do begins[v] = k end


-- Match Lua string in string <s> starting at position <pos>.
-- Returns <string>, <posnew>, where <string> is the matched
-- string (or nil on no match) and <posnew> is the character
-- following the match (or <pos> on no match).
-- Supports all Lua string syntax: "...", '...', [[...]], [=[...]=], etc.
local function match_string(s, pos)
  pos = pos or 1
  local posa = pos
  local c = s:sub(pos,pos)
  if c == '"' or c == "'" then
    pos = pos + 1
    while 1 do
      pos = assert(s:find("[" .. c .. "\\]", pos), 'syntax error')
      if s:sub(pos,pos) == c then
        local part = s:sub(posa, pos)
        return part, pos + 1
      else
        pos = pos + 2
      end
    end
  else
    local sc = s:match("^%[(=*)%[", pos)
    if sc then
      local _; _, pos = s:find("%]" .. sc .. "%]", pos)
      assert(pos)
      local part = s:sub(posa, pos)
      return part, pos + 1
    else
      return nil, pos
    end
  end
end
M.match_string = match_string


-- Match bracketed Lua expression, e.g. "(...)", "{...}", "[...]", "[[...]]",
-- [=[...]=], etc.
-- Function interface is similar to match_string.
local function match_bracketed(s, pos)
  pos = pos or 1
  local posa = pos
  local ca = s:sub(pos,pos)
  if not ends[ca] then
    return nil, pos
  end
  local stack = {}
  while 1 do
    pos = s:find('[%(%{%[%)%}%]\"\']', pos)
    assert(pos, 'syntax error: unbalanced')
    local c = s:sub(pos,pos)
    if c == '"' or c == "'" then
      local part; part, pos = match_string(s, pos)
      assert(part)
    elseif ends[c] then -- open
      local mid, posb
      if c == '[' then mid, posb = s:match('^%[(=*)%[()', pos) end
      if mid then
        pos = s:match('%]' .. mid .. '%]()', posb)
        assert(pos, 'syntax error: long string not terminated')
        if #stack == 0 then
          local part = s:sub(posa, pos-1)
          return part, pos
        end
      else
        stack[#stack+1] = c
        pos = pos + 1
      end
    else -- close
      assert(stack[#stack] == assert(begins[c]), 'syntax error: unbalanced')
      stack[#stack] = nil
      if #stack == 0 then
        local part = s:sub(posa, pos)
        return part, pos+1
      end
      pos = pos + 1
    end
  end
end
M.match_bracketed = match_bracketed


-- Match Lua comment, e.g. "--...\n", "--[[...]]", "--[=[...]=]", etc.
-- Function interface is similar to match_string.
local function match_comment(s, pos)
  pos = pos or 1
  if s:sub(pos, pos+1) ~= '--' then
    return nil, pos
  end
  pos = pos + 2
  local partt, post = match_string(s, pos)
  if partt then
    return '--' .. partt, post
  end
  local part; part, pos = s:match('^([^\n]*\n?)()', pos)
  return '--' .. part, pos
end


-- Match Lua expression, e.g. "a + b * c[e]".
-- Function interface is similar to match_string.
local wordop = {['and']=true, ['or']=true, ['not']=true}
local is_compare = {['>']=true, ['<']=true, ['~']=true}
local function match_expression(s, pos)
  pos = pos or 1
  local _
  local posa = pos
  local lastident
  local poscs, posce
  while pos do
    local c = s:sub(pos,pos)
    if c == '"' or c == "'" or c == '[' and s:find('^[=%[]', pos+1) then
      local part; part, pos = match_string(s, pos)
      assert(part, 'syntax error')
    elseif c == '-' and s:sub(pos+1,pos+1) == '-' then
      -- note: handle adjacent comments in loop to properly support
      -- backtracing (poscs/posce).
      poscs = pos
      while s:sub(pos,pos+1) == '--' do
        local part; part, pos = match_comment(s, pos)
        assert(part)
        pos = s:match('^%s*()', pos)
        posce = pos
      end
    elseif c == '(' or c == '{' or c == '[' then
      _, pos = match_bracketed(s, pos)
    elseif c == '=' and s:sub(pos+1,pos+1) == '=' then
      pos = pos + 2  -- skip over two-char op containing '='
    elseif c == '=' and is_compare[s:sub(pos-1,pos-1)] then
      pos = pos + 1  -- skip over two-char op containing '='
    elseif c:match'^[%)%}%];,=]' then
      local part = s:sub(posa, pos-1)
      return part, pos
    elseif c:match'^[%w_]' then
      local newident,newpos = s:match('^([%w_]+)()', pos)
      if pos ~= posa and not wordop[newident] then -- non-first ident
        local pose = ((posce == pos) and poscs or pos) - 1
        while s:match('^%s', pose) do pose = pose - 1 end
        local ce = s:sub(pose,pose)
        if ce:match'[%)%}\'\"%]]' or
           ce:match'[%w_]' and not wordop[lastident]
        then
          local part = s:sub(posa, pos-1)
          return part, pos
        end
      end
      lastident, pos = newident, newpos
    else
      pos = pos + 1
    end
    pos = s:find('[%(%{%[%)%}%]\"\';,=%w_%-]', pos)
  end
  local part = s:sub(posa, #s)
  return part, #s+1
end
M.match_expression = match_expression


-- Match name list (zero or more names).  E.g. "a,b,c"
-- Function interface is similar to match_string,
-- but returns array as match.
local function match_namelist(s, pos)
  pos = pos or 1
  local list = {}
  while 1 do
    local c = #list == 0 and '^' or '^%s*,%s*'
    local item, post = s:match(c .. '([%a_][%w_]*)%s*()', pos)
    if item then pos = post else break end
    list[#list+1] = item
  end
  return list, pos
end
M.match_namelist = match_namelist


-- Match expression list (zero or more expressions).  E.g. "a+b,b*c".
-- Function interface is similar to match_string,
-- but returns array as match.
local function match_explist(s, pos)
  pos = pos or 1
  local list = {}
  while 1 do
    if #list ~= 0 then
      local post = s:match('^%s*,%s*()', pos)
      if post then pos = post else break end
    end
    local item; item, pos = match_expression(s, pos)
    assert(item, 'syntax error')
    list[#list+1] = item
  end
  return list, pos
end
M.match_explist = match_explist


-- Replace snippets of code in Lua code string <s>
-- using replacement function f(u,sin) --> sout.
-- <u> is the type of snippet ('c' = comment, 's' = string,
-- 'e' = any other code).
-- Snippet is replaced with <sout> (unless <sout> is nil or false, in
-- which case the original snippet is kept)
-- This is somewhat analogous to string.gsub .
local function gsub(s, f)
  local pos = 1
  local posa = 1
  local sret = ''
  while 1 do
    pos = s:find('[%-\'\"%[]', pos)
    if not pos then break end
    if s:match('^%-%-', pos) then
      local exp = s:sub(posa, pos-1)
      if #exp > 0 then sret = sret .. (f('e', exp) or exp) end
      local comment; comment, pos = match_comment(s, pos)
      sret = sret .. (f('c', assert(comment)) or comment)
      posa = pos
    else
      local posb = s:find('^[\'\"%[]', pos)
      local str
      if posb then str, pos = match_string(s, posb) end
      if str then
        local exp = s:sub(posa, posb-1)
        if #exp > 0 then sret = sret .. (f('e', exp) or exp) end
        sret = sret .. (f('s', str) or str)
        posa = pos
      else
        pos = pos + 1
      end
    end
  end
  local exp = s:sub(posa)
  if #exp > 0 then sret = sret .. (f('e', exp) or exp) end
  return sret
end
M.gsub = gsub


return M

end,

["pl.Map"] = function()
--------------------
-- Module: 'pl.Map'
--------------------
--- A Map class.
--
--    > Map = require 'pl.Map'
--    > m = Map{one=1,two=2}
--    > m:update {three=3,four=4,two=20}
--    > = m == M{one=1,two=20,three=3,four=4}
--    true
--
-- Dependencies: `pl.utils`, `pl.class`, `pl.tablex`, `pl.pretty`
-- @classmod pl.Map

local tablex = require 'pl.tablex'
local utils = require 'pl.utils'
local stdmt = utils.stdmt
local deepcompare = tablex.deepcompare

local pretty_write = require 'pl.pretty' . write
local Map = stdmt.Map
local Set = stdmt.Set

local class = require 'pl.class'

-- the Map class ---------------------
class(nil,nil,Map)

function Map:_init (t)
    local mt = getmetatable(t)
    if mt == Set or mt == Map then
        self:update(t)
    else
        return t -- otherwise assumed to be a map-like table
    end
end


local function makelist(t)
    return setmetatable(t, require('pl.List'))
end

--- list of keys.
Map.keys = tablex.keys

--- list of values.
Map.values = tablex.values

--- return an iterator over all key-value pairs.
function Map:iter ()
    return pairs(self)
end

--- return a List of all key-value pairs, sorted by the keys.
function Map:items()
    local ls = makelist(tablex.pairmap (function (k,v) return makelist {k,v} end, self))
    ls:sort(function(t1,t2) return t1[1] < t2[1] end)
    return ls
end

--- set a value in the map if it doesn't exist yet.
-- @param key the key
-- @param default value to set
-- @return the value stored in the map (existing value, or the new value)
function Map:setdefault(key, default)
    local val = self[key]
    if val ~= nil then
        return val
    end
    self:set(key,default)
   return default
end

--- size of map.
-- note: this is a relatively expensive operation!
-- @class function
-- @name Map:len
Map.len = tablex.size

--- put a value into the map.
-- This will remove the key if the value is `nil`
-- @param key the key
-- @param val the value
function Map:set (key,val)
    self[key] = val
end

--- get a value from the map.
-- @param key the key
-- @return the value, or nil if not found.
function Map:get (key)
    return rawget(self,key)
end

local index_by = tablex.index_by

--- get a list of values indexed by a list of keys.
-- @param keys a list-like table of keys
-- @return a new list
function Map:getvalues (keys)
    return makelist(index_by(self,keys))
end

--- update the map using key/value pairs from another table.
-- @tab table
-- @function Map:update
Map.update = tablex.update

--- equality between maps.
-- @within metamethods
-- @tparam Map m another map.
function Map:__eq (m)
    -- note we explicitly ask deepcompare _not_ to use __eq!
    return deepcompare(self,m,true)
end

--- string representation of a map.
-- @within metamethods
function Map:__tostring ()
    return pretty_write(self,'')
end

return Map

end,

["pl.MultiMap"] = function()
--------------------
-- Module: 'pl.MultiMap'
--------------------
--- MultiMap, a Map which has multiple values per key.
--
-- Dependencies: `pl.utils`, `pl.class`, `pl.List`, `pl.Map`
-- @classmod pl.MultiMap

local utils = require 'pl.utils'
local class = require 'pl.class'
local List = require 'pl.List'
local Map = require 'pl.Map'

-- MultiMap is a standard MT
local MultiMap = utils.stdmt.MultiMap

class(Map,nil,MultiMap)
MultiMap._name = 'MultiMap'

function MultiMap:_init (t)
    if not t then return end
    self:update(t)
end

--- update a MultiMap using a table.
-- @param t either a Multimap or a map-like table.
-- @return the map
function MultiMap:update (t)
    utils.assert_arg(1,t,'table')
    if Map:class_of(t) then
        for k,v in pairs(t) do
            self[k] = List()
            self[k]:append(v)
        end
    else
        for k,v in pairs(t) do
            self[k] = List(v)
        end
    end
end

--- add a new value to a key.  Setting a nil value removes the key.
-- @param key the key
-- @param val the value
-- @return the map
function MultiMap:set (key,val)
    if val == nil then
        self[key] = nil
    else
        if not self[key] then
            self[key] = List()
        end
        self[key]:append(val)
    end
end

return MultiMap

end,

["pl.operator"] = function()
--------------------
-- Module: 'pl.operator'
--------------------
--- Lua operators available as functions.
--
-- (similar to the Python module of the same name)
--
-- There is a module field `optable` which maps the operator strings
-- onto these functions, e.g. `operator.optable['()']==operator.call`
--
-- Operator strings like '>' and '{}' can be passed to most Penlight functions
-- expecting a function argument.
--
-- @module pl.operator

local strfind = string.find

local operator = {}

--- apply function to some arguments **()**
-- @param fn a function or callable object
-- @param ... arguments
function operator.call(fn,...)
    return fn(...)
end

--- get the indexed value from a table **[]**
-- @param t a table or any indexable object
-- @param k the key
function  operator.index(t,k)
    return t[k]
end

--- returns true if arguments are equal **==**
-- @param a value
-- @param b value
function  operator.eq(a,b)
    return a==b
end

--- returns true if arguments are not equal **~=**
 -- @param a value
-- @param b value
function  operator.neq(a,b)
    return a~=b
end

--- returns true if a is less than b **<**
-- @param a value
-- @param b value
function  operator.lt(a,b)
    return a < b
end

--- returns true if a is less or equal to b **<=**
-- @param a value
-- @param b value
function  operator.le(a,b)
    return a <= b
end

--- returns true if a is greater than b **>**
-- @param a value
-- @param b value
function  operator.gt(a,b)
    return a > b
end

--- returns true if a is greater or equal to b **>=**
-- @param a value
-- @param b value
function  operator.ge(a,b)
    return a >= b
end

--- returns length of string or table **#**
-- @param a a string or a table
function  operator.len(a)
    return #a
end

--- add two values **+**
-- @param a value
-- @param b value
function  operator.add(a,b)
    return a+b
end

--- subtract b from a **-**
-- @param a value
-- @param b value
function  operator.sub(a,b)
    return a-b
end

--- multiply two values __*__
-- @param a value
-- @param b value
function  operator.mul(a,b)
    return a*b
end

--- divide first value by second **/**
-- @param a value
-- @param b value
function  operator.div(a,b)
    return a/b
end

--- raise first to the power of second **^**
-- @param a value
-- @param b value
function  operator.pow(a,b)
    return a^b
end

--- modulo; remainder of a divided by b **%**
-- @param a value
-- @param b value
function  operator.mod(a,b)
    return a%b
end

--- concatenate two values (either strings or `__concat` defined) **..**
-- @param a value
-- @param b value
function  operator.concat(a,b)
    return a..b
end

--- return the negative of a value **-**
-- @param a value
function  operator.unm(a)
    return -a
end

--- false if value evaluates as true **not**
-- @param a value
function  operator.lnot(a)
    return not a
end

--- true if both values evaluate as true **and**
-- @param a value
-- @param b value
function  operator.land(a,b)
    return a and b
end

--- true if either value evaluate as true **or**
-- @param a value
-- @param b value
function  operator.lor(a,b)
    return a or b
end

--- make a table from the arguments **{}**
-- @param ... non-nil arguments
-- @return a table
function  operator.table (...)
    return {...}
end

--- match two strings **~**.
-- uses @{string.find}
function  operator.match (a,b)
    return strfind(a,b)~=nil
end

--- the null operation.
-- @param ... arguments
-- @return the arguments
function  operator.nop (...)
    return ...
end

---- Map from operator symbol to function.
-- Most of these map directly from operators;
-- But note these extras
--
--  * __'()'__  `call`
--  * __'[]'__  `index`
--  * __'{}'__ `table`
--  * __'~'__   `match`
--
-- @table optable
-- @field operator
 operator.optable = {
    ['+']=operator.add,
    ['-']=operator.sub,
    ['*']=operator.mul,
    ['/']=operator.div,
    ['%']=operator.mod,
    ['^']=operator.pow,
    ['..']=operator.concat,
    ['()']=operator.call,
    ['[]']=operator.index,
    ['<']=operator.lt,
    ['<=']=operator.le,
    ['>']=operator.gt,
    ['>=']=operator.ge,
    ['==']=operator.eq,
    ['~=']=operator.neq,
    ['#']=operator.len,
    ['and']=operator.land,
    ['or']=operator.lor,
    ['{}']=operator.table,
    ['~']=operator.match,
    ['']=operator.nop,
}

return operator

end,

["pl.OrderedMap"] = function()
--------------------
-- Module: 'pl.OrderedMap'
--------------------
--- OrderedMap, a map which preserves ordering.
--
-- Derived from `pl.Map`.
--
-- Dependencies: `pl.utils`, `pl.tablex`, `pl.class`, `pl.List`, `pl.Map`
-- @classmod pl.OrderedMap

local tablex = require 'pl.tablex'
local utils = require 'pl.utils'
local List = require 'pl.List'
local index_by,tsort,concat = tablex.index_by,table.sort,table.concat

local class = require 'pl.class'
local Map = require 'pl.Map'

local OrderedMap = class(Map)
OrderedMap._name = 'OrderedMap'

local rawset = rawset

--- construct an OrderedMap.
-- Will throw an error if the argument is bad.
-- @param t optional initialization table, same as for @{OrderedMap:update}
function OrderedMap:_init (t)
    rawset(self,'_keys',List())
    if t then
        local map,err = self:update(t)
        if not map then error(err,2) end
    end
end

local assert_arg,raise = utils.assert_arg,utils.raise

--- update an OrderedMap using a table.
-- If the table is itself an OrderedMap, then its entries will be appended.
-- if it s a table of the form `{{key1=val1},{key2=val2},...}` these will be appended.
--
-- Otherwise, it is assumed to be a map-like table, and order of extra entries is arbitrary.
-- @tab t a table.
-- @return the map, or nil in case of error
-- @return the error message
function OrderedMap:update (t)
    assert_arg(1,t,'table')
    if OrderedMap:class_of(t) then
       for k,v in t:iter() do
           self:set(k,v)
       end
    elseif #t > 0 then -- an array must contain {key=val} tables
       if type(t[1]) == 'table' then
           for _,pair in ipairs(t) do
               local key,value = next(pair)
               if not key then return raise 'empty pair initialization table' end
               self:set(key,value)
           end
       else
           return raise 'cannot use an array to initialize an OrderedMap'
       end
    else
       for k,v in pairs(t) do
           self:set(k,v)
       end
    end
   return self
end

--- set the key's value.   This key will be appended at the end of the map.
--
-- If the value is nil, then the key is removed.
-- @param key the key
-- @param val the value
-- @return the map
function OrderedMap:set (key,val)
    if rawget(self, key) == nil and val ~= nil then -- new key
        self._keys:append(key) -- we keep in order
        rawset(self,key,val)  -- don't want to provoke __newindex!
    else -- existing key-value pair
        if val == nil then
            self._keys:remove_value(key)
            rawset(self,key,nil)
        else
            self[key] = val
        end
    end
    return self
end

OrderedMap.__newindex = OrderedMap.set

--- insert a key/value pair before a given position.
-- Note: if the map already contains the key, then this effectively
-- moves the item to the new position by first removing at the old position.
-- Has no effect if the key does not exist and val is nil
-- @int pos a position starting at 1
-- @param key the key
-- @param val the value; if nil use the old value
function OrderedMap:insert (pos,key,val)
    local oldval = self[key]
    val = val or oldval
    if oldval then
        self._keys:remove_value(key)
    end
    if val then
        self._keys:insert(pos,key)
        rawset(self,key,val)
    end
    return self
end

--- return the keys in order.
-- (Not a copy!)
-- @return List
function OrderedMap:keys ()
    return self._keys
end

--- return the values in order.
-- this is relatively expensive.
-- @return List
function OrderedMap:values ()
    return List(index_by(self,self._keys))
end

--- sort the keys.
-- @func cmp a comparison function as for @{table.sort}
-- @return the map
function OrderedMap:sort (cmp)
    tsort(self._keys,cmp)
    return self
end

--- iterate over key-value pairs in order.
function OrderedMap:iter ()
    local i = 0
    local keys = self._keys
    local idx
    return function()
        i = i + 1
        if i > #keys then return nil end
        idx = keys[i]
        return idx,self[idx]
    end
end

--- iterate over an ordered map (5.2).
-- @within metamethods
-- @function OrderedMap:__pairs
OrderedMap.__pairs = OrderedMap.iter

--- string representation of an ordered map.
-- @within metamethods
function OrderedMap:__tostring ()
    local res = {}
    for i,v in ipairs(self._keys) do
        local val = self[v]
        local vs = tostring(val)
        if type(val) ~= 'number' then
            vs = '"'..vs..'"'
        end
        res[i] = tostring(v)..'='..vs
    end
    return '{'..concat(res,',')..'}'
end

return OrderedMap




end,

["pl.path"] = function()
--------------------
-- Module: 'pl.path'
--------------------
--- Path manipulation and file queries.
--
-- This is modelled after Python's os.path library (10.1); see @{04-paths.md|the Guide}.
--
-- NOTE: the functions assume the paths being dealt with to originate
-- from the OS the application is running on. Windows drive letters are not
-- to be used when running on a Unix system for example. The one exception
-- is Windows paths to allow both forward and backward slashes (since Lua
-- also accepts those)
--
-- Dependencies: `pl.utils`, `lfs`
-- @module pl.path

-- imports and locals
local _G = _G
local sub = string.sub
local getenv = os.getenv
local tmpnam = os.tmpname
local package = package
local append, concat, remove = table.insert, table.concat, table.remove
local utils = require 'pl.utils'
local assert_string,raise = utils.assert_string,utils.raise

local res,lfs = _G.pcall(_G.require,'lfs')
if not res then
    error("pl.path requires LuaFileSystem")
end

local attrib = lfs.attributes
local currentdir = lfs.currentdir
local link_attrib = lfs.symlinkattributes

local path = {}

local function err_func(name, param, err, code)
  local ret = ("%s failed"):format(tostring(name))
  if param ~= nil then
    ret = ret .. (" for '%s'"):format(tostring(param))
  end
  ret = ret .. (": %s"):format(tostring(err))
  if code ~= nil then
    ret = ret .. (" (code %s)"):format(tostring(code))
  end
  return ret
end

--- Lua iterator over the entries of a given directory.
-- Implicit link to [`luafilesystem.dir`](https://keplerproject.github.io/luafilesystem/manual.html#reference)
-- @function dir
path.dir = lfs.dir

--- Creates a directory.
-- Implicit link to [`luafilesystem.mkdir`](https://keplerproject.github.io/luafilesystem/manual.html#reference)
-- @function mkdir
path.mkdir = function(d)
  local ok, err, code = lfs.mkdir(d)
  if not ok then
    return ok, err_func("mkdir", d, err, code), code
  end
  return ok, err, code
end

--- Removes a directory.
-- Implicit link to [`luafilesystem.rmdir`](https://keplerproject.github.io/luafilesystem/manual.html#reference)
-- @function rmdir
path.rmdir = function(d)
  local ok, err, code = lfs.rmdir(d)
  if not ok then
    return ok, err_func("rmdir", d, err, code), code
  end
  return ok, err, code
end

--- Gets attributes.
-- Implicit link to [`luafilesystem.attributes`](https://keplerproject.github.io/luafilesystem/manual.html#reference)
-- @function attrib
path.attrib = function(d, r)
  local ok, err, code = attrib(d, r)
  if not ok then
    return ok, err_func("attrib", d, err, code), code
  end
  return ok, err, code
end

--- Get the working directory.
-- Implicit link to [`luafilesystem.currentdir`](https://keplerproject.github.io/luafilesystem/manual.html#reference)
-- @function currentdir
path.currentdir = function()
  local ok, err, code = currentdir()
  if not ok then
    return ok, err_func("currentdir", nil, err, code), code
  end
  return ok, err, code
end

--- Gets symlink attributes.
-- Implicit link to [`luafilesystem.symlinkattributes`](https://keplerproject.github.io/luafilesystem/manual.html#reference)
-- @function link_attrib
path.link_attrib = function(d, r)
  local ok, err, code = link_attrib(d, r)
  if not ok then
    return ok, err_func("link_attrib", d, err, code), code
  end
  return ok, err, code
end

--- Changes the working directory.
-- On Windows, if a drive is specified, it also changes the current drive. If
-- only specifying the drive, it will only switch drive, but not modify the path.
-- Implicit link to [`luafilesystem.chdir`](https://keplerproject.github.io/luafilesystem/manual.html#reference)
-- @function chdir
path.chdir = function(d)
  local ok, err, code = lfs.chdir(d)
  if not ok then
    return ok, err_func("chdir", d, err, code), code
  end
  return ok, err, code
end

--- is this a directory?
-- @string P A file path
function path.isdir(P)
    assert_string(1,P)
    if P:match("\\$") then
        P = P:sub(1,-2)
    end
    return attrib(P,'mode') == 'directory'
end

--- is this a file?
-- @string P A file path
function path.isfile(P)
    assert_string(1,P)
    return attrib(P,'mode') == 'file'
end

-- is this a symbolic link?
-- @string P A file path
function path.islink(P)
    assert_string(1,P)
    if link_attrib then
        return link_attrib(P,'mode')=='link'
    else
        return false
    end
end

--- return size of a file.
-- @string P A file path
function path.getsize(P)
    assert_string(1,P)
    return attrib(P,'size')
end

--- does a path exist?
-- @string P A file path
-- @return the file path if it exists (either as file, directory, socket, etc), nil otherwise
function path.exists(P)
    assert_string(1,P)
    return attrib(P,'mode') ~= nil and P
end

--- Return the time of last access as the number of seconds since the epoch.
-- @string P A file path
function path.getatime(P)
    assert_string(1,P)
    return attrib(P,'access')
end

--- Return the time of last modification as the number of seconds since the epoch.
-- @string P A file path
function path.getmtime(P)
    assert_string(1,P)
    return attrib(P,'modification')
end

---Return the system's ctime as the number of seconds since the epoch.
-- @string P A file path
function path.getctime(P)
    assert_string(1,P)
    return path.attrib(P,'change')
end


local function at(s,i)
    return sub(s,i,i)
end

path.is_windows = utils.is_windows

local sep, other_sep, seps
-- constant sep is the directory separator for this platform.
-- constant dirsep is the separator in the PATH environment variable
if path.is_windows then
    path.sep = '\\'; other_sep = '/'
    path.dirsep = ';'
    seps = { ['/'] = true, ['\\'] = true }
else
    path.sep = '/'
    path.dirsep = ':'
    seps = { ['/'] = true }
end
sep = path.sep

--- are we running Windows?
-- @class field
-- @name path.is_windows

--- path separator for this platform.
-- @class field
-- @name path.sep

--- separator for PATH for this platform
-- @class field
-- @name path.dirsep

--- given a path, return the directory part and a file part.
-- if there's no directory part, the first value will be empty
-- @string P A file path
-- @return directory part
-- @return file part
-- @usage
-- local dir, file = path.splitpath("some/dir/myfile.txt")
-- assert(dir == "some/dir")
-- assert(file == "myfile.txt")
--
-- local dir, file = path.splitpath("some/dir/")
-- assert(dir == "some/dir")
-- assert(file == "")
--
-- local dir, file = path.splitpath("some_dir")
-- assert(dir == "")
-- assert(file == "some_dir")
function path.splitpath(P)
    assert_string(1,P)
    local i = #P
    local ch = at(P,i)
    while i > 0 and ch ~= sep and ch ~= other_sep do
        i = i - 1
        ch = at(P,i)
    end
    if i == 0 then
        return '',P
    else
        return sub(P,1,i-1), sub(P,i+1)
    end
end

--- return an absolute path.
-- @string P A file path
-- @string[opt] pwd optional start path to use (default is current dir)
function path.abspath(P,pwd)
    assert_string(1,P)
    if pwd then assert_string(2,pwd) end
    local use_pwd = pwd ~= nil
    if not use_pwd and not currentdir() then return P end
    P = P:gsub('[\\/]$','')
    pwd = pwd or currentdir()
    if not path.isabs(P) then
        P = path.join(pwd,P)
    elseif path.is_windows and not use_pwd and at(P,2) ~= ':' and at(P,2) ~= '\\' then
        P = pwd:sub(1,2)..P -- attach current drive to path like '\\fred.txt'
    end
    return path.normpath(P)
end

--- given a path, return the root part and the extension part.
-- if there's no extension part, the second value will be empty
-- @string P A file path
-- @treturn string root part (everything upto the "."", maybe empty)
-- @treturn string extension part (including the ".", maybe empty)
-- @usage
-- local file_path, ext = path.splitext("/bonzo/dog_stuff/cat.txt")
-- assert(file_path == "/bonzo/dog_stuff/cat")
-- assert(ext == ".txt")
--
-- local file_path, ext = path.splitext("")
-- assert(file_path == "")
-- assert(ext == "")
function path.splitext(P)
    assert_string(1,P)
    local i = #P
    local ch = at(P,i)
    while i > 0 and ch ~= '.' do
        if seps[ch] then
            return P,''
        end
        i = i - 1
        ch = at(P,i)
    end
    if i == 0 then
        return P,''
    else
        return sub(P,1,i-1),sub(P,i)
    end
end

--- return the directory part of a path
-- @string P A file path
-- @treturn string everything before the last dir-separator
-- @see splitpath
-- @usage
-- path.dirname("/some/path/file.txt")   -- "/some/path"
-- path.dirname("file.txt")              -- "" (empty string)
function path.dirname(P)
    assert_string(1,P)
    local p1 = path.splitpath(P)
    return p1
end

--- return the file part of a path
-- @string P A file path
-- @treturn string
-- @see splitpath
-- @usage
-- path.basename("/some/path/file.txt")  -- "file.txt"
-- path.basename("/some/path/file/")     -- "" (empty string)
function path.basename(P)
    assert_string(1,P)
    local _,p2 = path.splitpath(P)
    return p2
end

--- get the extension part of a path.
-- @string P A file path
-- @treturn string
-- @see splitext
-- @usage
-- path.extension("/some/path/file.txt") -- ".txt"
-- path.extension("/some/path/file_txt") -- "" (empty string)
function path.extension(P)
    assert_string(1,P)
    local _,p2 = path.splitext(P)
    return p2
end

--- is this an absolute path?
-- @string P A file path
-- @usage
-- path.isabs("hello/path")    -- false
-- path.isabs("/hello/path")   -- true
-- -- Windows;
-- path.isabs("hello\path")    -- false
-- path.isabs("\hello\path")   -- true
-- path.isabs("C:\hello\path") -- true
-- path.isabs("C:hello\path")  -- false
function path.isabs(P)
    assert_string(1,P)
    if path.is_windows and at(P,2) == ":" then
        return seps[at(P,3)] ~= nil
    end
    return seps[at(P,1)] ~= nil
end

--- return the path resulting from combining the individual paths.
-- if the second (or later) path is absolute, we return the last absolute path (joined with any non-absolute paths following).
-- empty elements (except the last) will be ignored.
-- @string p1 A file path
-- @string p2 A file path
-- @string ... more file paths
-- @treturn string the combined path
-- @usage
-- path.join("/first","second","third")   -- "/first/second/third"
-- path.join("first","second/third")      -- "first/second/third"
-- path.join("/first","/second","third")  -- "/second/third"
function path.join(p1,p2,...)
    assert_string(1,p1)
    assert_string(2,p2)
    if select('#',...) > 0 then
        local p = path.join(p1,p2)
        local args = {...}
        for i = 1,#args do
            assert_string(i,args[i])
            p = path.join(p,args[i])
        end
        return p
    end
    if path.isabs(p2) then return p2 end
    local endc = at(p1,#p1)
    if endc ~= path.sep and endc ~= other_sep and endc ~= "" then
        p1 = p1..path.sep
    end
    return p1..p2
end

--- normalize the case of a pathname. On Unix, this returns the path unchanged,
-- for Windows it converts;
--
-- * the path to lowercase
-- * forward slashes to backward slashes
-- @string P A file path
-- @usage path.normcase("/Some/Path/File.txt")
-- -- Windows: "\some\path\file.txt"
-- -- Others : "/Some/Path/File.txt"
function path.normcase(P)
    assert_string(1,P)
    if path.is_windows then
        return P:gsub('/','\\'):lower()
    else
        return P
    end
end

--- normalize a path name.
-- `A//B`, `A/./B`, and `A/foo/../B` all become `A/B`.
--
-- An empty path results in '.'.
-- @string P a file path
function path.normpath(P)
    assert_string(1,P)
    -- Split path into anchor and relative path.
    local anchor = ''
    if path.is_windows then
        if P:match '^\\\\' then -- UNC
            anchor = '\\\\'
            P = P:sub(3)
        elseif seps[at(P, 1)] then
            anchor = '\\'
            P = P:sub(2)
        elseif at(P, 2) == ':' then
            anchor = P:sub(1, 2)
            P = P:sub(3)
            if seps[at(P, 1)] then
                anchor = anchor..'\\'
                P = P:sub(2)
            end
        end
        P = P:gsub('/','\\')
    else
        -- According to POSIX, in path start '//' and '/' are distinct,
        -- but '///+' is equivalent to '/'.
        if P:match '^//' and at(P, 3) ~= '/' then
            anchor = '//'
            P = P:sub(3)
        elseif at(P, 1) == '/' then
            anchor = '/'
            P = P:match '^/*(.*)$'
        end
    end
    local parts = {}
    for part in P:gmatch('[^'..sep..']+') do
        if part == '..' then
            if #parts ~= 0 and parts[#parts] ~= '..' then
                remove(parts)
            else
                append(parts, part)
            end
        elseif part ~= '.' then
            append(parts, part)
        end
    end
    P = anchor..concat(parts, sep)
    if P == '' then P = '.' end
    return P
end

--- relative path from current directory or optional start point
-- @string P a path
-- @string[opt] start optional start point (default current directory)
function path.relpath (P,start)
    assert_string(1,P)
    if start then assert_string(2,start) end
    local split,min,append = utils.split, math.min, table.insert
    P = path.abspath(P,start)
    start = start or currentdir()
    local compare
    if path.is_windows then
        P = P:gsub("/","\\")
        start = start:gsub("/","\\")
        compare = function(v) return v:lower() end
    else
        compare = function(v) return v end
    end
    local startl, Pl = split(start,sep), split(P,sep)
    local n = min(#startl,#Pl)
    if path.is_windows and n > 0 and at(Pl[1],2) == ':' and Pl[1] ~= startl[1] then
        return P
    end
    local k = n+1 -- default value if this loop doesn't bail out!
    for i = 1,n do
        if compare(startl[i]) ~= compare(Pl[i]) then
            k = i
            break
        end
    end
    local rell = {}
    for i = 1, #startl-k+1 do rell[i] = '..' end
    if k <= #Pl then
        for i = k,#Pl do append(rell,Pl[i]) end
    end
    return table.concat(rell,sep)
end


--- Replace a starting '~' with the user's home directory.
-- In windows, if HOME isn't set, then USERPROFILE is used in preference to
-- HOMEDRIVE HOMEPATH. This is guaranteed to be writeable on all versions of Windows.
-- @string P A file path
function path.expanduser(P)
    assert_string(1,P)
    if at(P,1) == '~' then
        local home = getenv('HOME')
        if not home then -- has to be Windows
            home = getenv 'USERPROFILE' or (getenv 'HOMEDRIVE' .. getenv 'HOMEPATH')
        end
        return home..sub(P,2)
    else
        return P
    end
end


---Return a suitable full path to a new temporary file name.
-- unlike os.tmpname(), it always gives you a writeable path (uses TEMP environment variable on Windows)
function path.tmpname ()
    local res = tmpnam()
    -- On Windows if Lua is compiled using MSVC14 os.tmpname
    -- already returns an absolute path within TEMP env variable directory,
    -- no need to prepend it.
    if path.is_windows and not res:find(':') then
        res = getenv('TEMP')..res
    end
    return res
end

--- return the largest common prefix path of two paths.
-- @string path1 a file path
-- @string path2 a file path
-- @return the common prefix (Windows: separators will be normalized, casing will be original)
function path.common_prefix (path1,path2)
    assert_string(1,path1)
    assert_string(2,path2)
    -- get them in order!
    if #path1 > #path2 then path2,path1 = path1,path2 end
    local compare
    if path.is_windows then
        path1 = path1:gsub("/", "\\")
        path2 = path2:gsub("/", "\\")
        compare = function(v) return v:lower() end
    else
        compare = function(v) return v end
    end
    for i = 1,#path1 do
        if compare(at(path1,i)) ~= compare(at(path2,i)) then
            local cp = path1:sub(1,i-1)
            if at(path1,i-1) ~= sep then
                cp = path.dirname(cp)
            end
            return cp
        end
    end
    if at(path2,#path1+1) ~= sep then path1 = path.dirname(path1) end
    return path1
    --return ''
end

--- return the full path where a particular Lua module would be found.
-- Both package.path and package.cpath is searched, so the result may
-- either be a Lua file or a shared library.
-- @string mod name of the module
-- @return on success: path of module, lua or binary
-- @return on error: nil, error string listing paths tried
function path.package_path(mod)
    assert_string(1,mod)
    local res, err1, err2
    res, err1 = package.searchpath(mod,package.path)
    if res then return res,true end
    res, err2 = package.searchpath(mod,package.cpath)
    if res then return res,false end
    return raise ('cannot find module on path\n' .. err1 .. "\n" .. err2)
end


---- finis -----
return path

end,

["pl.permute"] = function()
--------------------
-- Module: 'pl.permute'
--------------------
--- Permutation operations.
--
-- Dependencies: `pl.utils`, `pl.tablex`
-- @module pl.permute
local tablex = require 'pl.tablex'
local utils = require 'pl.utils'
local copy = tablex.deepcopy
local append = table.insert
local assert_arg = utils.assert_arg


local permute = {}


--- an iterator over all order-permutations of the elements of a list.
-- Please note that the same list is returned each time, so do not keep references!
-- @param a list-like table
-- @return an iterator which provides the next permutation as a list
function permute.order_iter(a)
    assert_arg(1,a,'table')

    local t = #a
    local stack = { 1 }
    local function iter()
        local h = #stack
        local n = t - h + 1

        local i = stack[h]
        if i > t then
            return
        end

        if n == 0 then
            table.remove(stack)
            h = h - 1

            stack[h] = stack[h] + 1
            return a

        elseif i <= n then

            -- put i-th element as the last one
            a[n], a[i] = a[i], a[n]

            -- generate all permutations of the other elements
            table.insert(stack, 1)

        else

            table.remove(stack)
            h = h - 1

            n = n + 1
            i = stack[h]

            -- restore i-th element
            a[n], a[i] = a[i], a[n]

            stack[h] = stack[h] + 1
        end
        return iter() -- tail-call
    end

    return iter
end


--- construct a table containing all the order-permutations of a list.
-- @param a list-like table
-- @return a table of tables
-- @usage permute.order_table {1,2,3} --> {{2,3,1},{3,2,1},{3,1,2},{1,3,2},{2,1,3},{1,2,3}}
function permute.order_table (a)
    assert_arg(1,a,'table')
    local res = {}
    for t in permute.iter(a) do
        append(res,copy(t))
    end
    return res
end



--- an iterator over all permutations of the elements of the given lists.
-- @param ... list-like tables, they are nil-safe if a length-field `n` is provided (see `utils.pack`)
-- @return an iterator which provides the next permutation as return values in the same order as the provided lists, preceeded by an index
-- @usage
-- local strs = utils.pack("one", nil, "three")  -- adds an 'n' field for nil-safety
-- local bools = utils.pack(true, false)
-- local iter = permute.list_iter(strs, bools)
--
-- print(iter())    --> 1, one, true
-- print(iter())    --> 2, nil, true
-- print(iter())    --> 3, three, true
-- print(iter())    --> 4, one, false
-- print(iter())    --> 5, nil, false
-- print(iter())    --> 6, three, false
function permute.list_iter(...)
  local elements = {...}
  local pointers = {}
  local sizes = {}
  local size = #elements
  for i, list in ipairs(elements) do
    assert_arg(i,list,'table')
    pointers[i] = 1
    sizes[i] = list.n or #list
  end
  local count = 0

  return function()
    if pointers[size] > sizes[size] then return end -- we're done
    count = count + 1
    local r = { n = #elements }
    local cascade_up = true
    for i = 1, size do
      r[i] = elements[i][pointers[i]]
      if cascade_up then
        pointers[i] = pointers[i] + 1
        if pointers[i] <= sizes[i] then
          -- this list is not done yet, stop cascade
          cascade_up = false
        else
          -- this list is done
          if i ~= size then
            -- reset pointer
            pointers[i] = 1
          end
        end
      end
    end
    return count, utils.unpack(r)
  end
end



--- construct a table containing all the permutations of a set of lists.
-- @param ... list-like tables, they are nil-safe if a length-field `n` is provided
-- @return a list of lists, the sub-lists have an 'n' field for nil-safety
-- @usage
-- local strs = utils.pack("one", nil, "three")  -- adds an 'n' field for nil-safety
-- local bools = utils.pack(true, false)
-- local results = permute.list_table(strs, bools)
-- -- results = {
-- --   { "one, true, n = 2 }
-- --   { nil, true, n = 2 },
-- --   { "three, true, n = 2 },
-- --   { "one, false, n = 2 },
-- --   { nil, false, n = 2 },
-- --   { "three", false, n = 2 },
-- -- }
function permute.list_table(...)
  local iter = permute.list_iter(...)
  local results = {}
  local i = 1
  while true do
    local values = utils.pack(iter())
    if values[1] == nil then return results end
    for i = 1, values.n do values[i] = values[i+1] end
    values.n = values.n - 1
    results[i] = values
    i = i + 1
  end
end


-- backward compat, to be deprecated

--- deprecated.
-- @param ...
-- @see permute.order_iter
function permute.iter(...)
  utils.raise_deprecation {
    source = "Penlight " .. utils._VERSION,
    message = "function 'iter' was renamed to 'order_iter'",
    version_removed = "2.0.0",
    deprecated_after = "1.9.2",
  }

  return permute.order_iter(...)
end

--- deprecated.
-- @param ...
-- @see permute.order_iter
function permute.table(...)
  utils.raise_deprecation {
    source = "Penlight " .. utils._VERSION,
    message = "function 'table' was renamed to 'order_table'",
    version_removed = "2.0.0",
    deprecated_after = "1.9.2",
  }

  return permute.order_table(...)
end

return permute

end,

["pl.pretty"] = function()
--------------------
-- Module: 'pl.pretty'
--------------------
--- Pretty-printing Lua tables.
-- Also provides a sandboxed Lua table reader and
-- a function to present large numbers in human-friendly format.
--
-- Dependencies: `pl.utils`, `pl.lexer`, `pl.stringx`, `debug`
-- @module pl.pretty

local append = table.insert
local concat = table.concat
local mfloor, mhuge = math.floor, math.huge
local mtype = math.type
local utils = require 'pl.utils'
local lexer = require 'pl.lexer'
local debug = require 'debug'
local quote_string = require'pl.stringx'.quote_string
local assert_arg = utils.assert_arg

local original_tostring = tostring

-- Patch tostring to format numbers with better precision
-- and to produce cross-platform results for
-- infinite values and NaN.
local function tostring(value)
    if type(value) ~= "number" then
        return original_tostring(value)
    elseif value ~= value then
        return "NaN"
    elseif value == mhuge then
        return "Inf"
    elseif value == -mhuge then
        return "-Inf"
    elseif (_VERSION ~= "Lua 5.3" or mtype(value) == "integer") and mfloor(value) == value then
        return ("%d"):format(value)
    else
        local res = ("%.14g"):format(value)
        if _VERSION == "Lua 5.3" and mtype(value) == "float" and not res:find("%.") then
            -- Number is internally a float but looks like an integer.
            -- Insert ".0" after first run of digits.
            res = res:gsub("%d+", "%0.0", 1)
        end
        return res
    end
end

local pretty = {}

local function save_global_env()
    local env = {}
    env.hook, env.mask, env.count = debug.gethook()

    -- env.hook is "external hook" if is a C hook function
    if env.hook~="external hook" then
        debug.sethook()
    end

    env.string_mt = getmetatable("")
    debug.setmetatable("", nil)
    return env
end

local function restore_global_env(env)
    if env then
        debug.setmetatable("", env.string_mt)
        if env.hook~="external hook" then
            debug.sethook(env.hook, env.mask, env.count)
        end
    end
end

--- Read a string representation of a Lua table.
-- This function loads and runs the string as Lua code, but bails out
-- if it contains a function definition.
-- Loaded string is executed in an empty environment.
-- @string s string to read in `{...}` format, possibly with some whitespace
-- before or after the curly braces. A single line comment may be present
-- at the beginning.
-- @return a table in case of success.
-- If loading the string failed, return `nil` and error message.
-- If executing loaded string failed, return `nil` and the error it raised.
function pretty.read(s)
    assert_arg(1,s,'string')
    if s:find '^%s*%-%-' then -- may start with a comment..
        s = s:gsub('%-%-.-\n','')
    end
    if not s:find '^%s*{' then return nil,"not a Lua table" end
    if s:find '[^\'"%w_]function[^\'"%w_]' then
        local tok = lexer.lua(s)
        for t,v in tok do
            if t == 'keyword' and v == 'function' then
                return nil,"cannot have functions in table definition"
            end
        end
    end
    s = 'return '..s
    local chunk,err = utils.load(s,'tbl','t',{})
    if not chunk then return nil,err end
    local global_env = save_global_env()
    local ok,ret = pcall(chunk)
    restore_global_env(global_env)
    if ok then return ret
    else
        return nil,ret
    end
end

--- Read a Lua chunk.
-- @string s Lua code.
-- @tab[opt] env environment used to run the code, empty by default.
-- @bool[opt] paranoid abort loading if any looping constructs a found in the code
-- and disable string methods.
-- @return the environment in case of success or `nil` and syntax or runtime error
-- if something went wrong.
function pretty.load (s, env, paranoid)
    env = env or {}
    if paranoid then
        local tok = lexer.lua(s)
        for t,v in tok do
            if t == 'keyword'
                and (v == 'for' or v == 'repeat' or v == 'function' or v == 'goto')
            then
                return nil,"looping not allowed"
            end
        end
    end
    local chunk,err = utils.load(s,'tbl','t',env)
    if not chunk then return nil,err end
    local global_env = paranoid and save_global_env()
    local ok,err = pcall(chunk)
    restore_global_env(global_env)
    if not ok then return nil,err end
    return env
end

local function quote_if_necessary (v)
    if not v then return ''
    else
        --AAS
        if v:find ' ' then v = quote_string(v) end
    end
    return v
end

local keywords

local function is_identifier (s)
    return type(s) == 'string' and s:find('^[%a_][%w_]*$') and not keywords[s]
end

local function quote (s)
    if type(s) == 'table' then
        return pretty.write(s,'')
    else
        --AAS
        return quote_string(s)-- ('%q'):format(tostring(s))
    end
end

local function index (numkey,key)
    --AAS
    if not numkey then
        key = quote(key)
         key = key:find("^%[") and (" " .. key .. " ") or key
    end
    return '['..key..']'
end


--- Create a string representation of a Lua table.
-- This function never fails, but may complain by returning an
-- extra value. Normally puts out one item per line, using
-- the provided indent; set the second parameter to an empty string
-- if you want output on one line.
--
-- *NOTE:* this is NOT a serialization function, not a full blown
-- debug function. Checkout out respectively the
-- [serpent](https://github.com/pkulchenko/serpent)
-- or [inspect](https://github.com/kikito/inspect.lua)
-- Lua modules for that if you need them.
-- @tab tbl Table to serialize to a string.
-- @string[opt] space The indent to use.
-- Defaults to two spaces; pass an empty string for no indentation.
-- @bool[opt] not_clever Pass `true` for plain output, e.g `{['key']=1}`.
-- Defaults to `false`.
-- @return a string
-- @return an optional error message
function pretty.write (tbl,space,not_clever)
    if type(tbl) ~= 'table' then
        local res = tostring(tbl)
        if type(tbl) == 'string' then return quote(tbl) end
        return res, 'not a table'
    end
    if not keywords then
        keywords = lexer.get_keywords()
    end
    local set = ' = '
    if space == '' then set = '=' end
    space = space or '  '
    local lines = {}
    local line = ''
    local tables = {}


    local function put(s)
        if #s > 0 then
            line = line..s
        end
    end

    local function putln (s)
        if #line > 0 then
            line = line..s
            append(lines,line)
            line = ''
        else
            append(lines,s)
        end
    end

    local function eat_last_comma ()
        local n = #lines
        local lastch = lines[n]:sub(-1,-1)
        if lastch == ',' then
            lines[n] = lines[n]:sub(1,-2)
        end
    end


    -- safe versions for iterators since 5.3+ honors metamethods that can throw
    -- errors
    local ipairs = function(t)
        local i = 0
        local ok, v
        local getter = function() return t[i] end
        return function()
                i = i + 1
                ok, v = pcall(getter)
                if v == nil or not ok then return end
                return i, t[i]
            end
    end
    local pairs = function(t)
        local k, v, ok
        local getter = function() return next(t, k) end
        return function()
                ok, k, v = pcall(getter)
                if not ok then return end
                return k, v
            end
    end

    local writeit
    writeit = function (t,oldindent,indent)
        local tp = type(t)
        if tp ~= 'string' and  tp ~= 'table' then
            putln(quote_if_necessary(tostring(t))..',')
        elseif tp == 'string' then
            -- if t:find('\n') then
            --     putln('[[\n'..t..']],')
            -- else
            --     putln(quote(t)..',')
            -- end
            --AAS
            putln(quote_string(t) ..",")
        elseif tp == 'table' then
            if tables[t] then
                putln('<cycle>,')
                return
            end
            tables[t] = true
            local newindent = indent..space
            putln('{')
            local used = {}
            if not not_clever then
                for i,val in ipairs(t) do
                    put(indent)
                    writeit(val,indent,newindent)
                    used[i] = true
                end
            end
            local ordered_keys = {}
            for k,v in pairs(t) do
               if type(k) ~= 'number' then
                  ordered_keys[#ordered_keys + 1] = k
               end
            end
            table.sort(ordered_keys, function (a, b)
                if type(a) == type(b)  and type(a) == 'string' then
                    return a < b
                end
                return type(a) == 'boolean' or (type(b) ~= 'boolean' and type(a) == 'table')
            end)
            local function write_entry (key, val)
                local tkey = type(key)
                local numkey = tkey == 'number'
                if not_clever then
                    key = tostring(key)
                    put(indent..index(numkey,key)..set)
                    writeit(val,indent,newindent)
                else
                    if not numkey or not used[key] then -- non-array indices
                        if tkey ~= 'string' then
                            key = tostring(key)
                        end
                        if numkey or not is_identifier(key) then
                            key = index(numkey,key)
                        end
                        put(indent..key..set)
                        writeit(val,indent,newindent)
                    end
                end
            end
            for i = 1, #ordered_keys do
                local key = ordered_keys[i]
                local val = t[key]
                write_entry(key, val)
            end
            for key,val in pairs(t) do
               if type(key) == 'number' then
                  write_entry(key, val)
               end
            end
            tables[t] = nil
            eat_last_comma()
            putln(oldindent..'},')
        else
            putln(tostring(t)..',')
        end
    end
    writeit(tbl,'',space)
    eat_last_comma()
    return concat(lines,#space > 0 and '\n' or '')
end

--- Dump a Lua table out to a file or stdout.
-- @tab t The table to write to a file or stdout.
-- @string[opt] filename File name to write too. Defaults to writing
-- to stdout.
function pretty.dump (t, filename)
    if not filename then
        print(pretty.write(t))
        return true
    else
        return utils.writefile(filename, pretty.write(t))
    end
end

--- Dump a series of arguments to stdout for debug purposes.
-- This function is attached to the module table `__call` method, to make it
-- extra easy to access. So the full:
--
--     print(require("pl.pretty").write({...}))
--
-- Can be shortened to:
--
--     require"pl.pretty" (...)
--
-- Any `nil` entries will be printed as `"<nil>"` to make them explicit.
-- @param ... the parameters to dump to stdout.
-- @usage
-- -- example debug output
-- require"pl.pretty" ("hello", nil, "world", { bye = "world", true} )
--
-- -- output:
-- {
--   ["arg 1"] = "hello",
--   ["arg 2"] = "<nil>",
--   ["arg 3"] = "world",
--   ["arg 4"] = {
--     true,
--     bye = "world"
--   }
-- }
function pretty.debug(...)
    local n = select("#", ...)
    local t = { ... }
    for i = 1, n do
        local value = t[i]
        if value == nil then
            value = "<nil>"
        end
        t[i] = nil
        t["arg " .. i] = value
    end

    print(pretty.write(t))
    return true
end


local memp,nump = {'B','KiB','MiB','GiB'},{'','K','M','B'}

local function comma (val)
    local thou = math.floor(val/1000)
    if thou > 0 then return comma(thou)..','.. tostring(val % 1000)
    else return tostring(val) end
end

--- Format large numbers nicely for human consumption.
-- @number num a number.
-- @string[opt] kind one of `'M'` (memory in `KiB`, `MiB`, etc.),
-- `'N'` (postfixes are `'K'`, `'M'` and `'B'`),
-- or `'T'` (use commas as thousands separator), `'N'` by default.
-- @int[opt] prec number of digits to use for `'M'` and `'N'`, `1` by default.
function pretty.number (num,kind,prec)
    local fmt = '%.'..(prec or 1)..'f%s'
    if kind == 'T' then
        return comma(num)
    else
        local postfixes, fact
        if kind == 'M' then
            fact = 1024
            postfixes = memp
        else
            fact = 1000
            postfixes = nump
        end
        local div = fact
        local k = 1
        while num >= div and k <= #postfixes do
            div = div * fact
            k = k + 1
        end
        div = div / fact
        if k > #postfixes then k = k - 1; div = div/fact end
        if k > 1 then
            return fmt:format(num/div,postfixes[k] or 'duh')
        else
            return num..postfixes[1]
        end
    end
end

return setmetatable(pretty, {
    __call = function(self, ...)
        return self.debug(...)
    end
})

end,

["pl.seq"] = function()
--------------------
-- Module: 'pl.seq'
--------------------
--- Manipulating iterators as sequences.
-- See @{07-functional.md.Sequences|The Guide}
--
-- Dependencies: `pl.utils`, `pl.types`, `debug`
-- @module pl.seq

local next,assert,pairs,tonumber,type,setmetatable = next,assert,pairs,tonumber,type,setmetatable
local strfind,format = string.find,string.format
local mrandom = math.random
local tsort,tappend = table.sort,table.insert
local io = io
local utils = require 'pl.utils'
local callable = require 'pl.types'.is_callable
local function_arg = utils.function_arg
local assert_arg = utils.assert_arg
local debug = require 'debug'

local seq = {}

-- given a number, return a function(y) which returns true if y > x
-- @param x a number
function seq.greater_than(x)
  return function(v)
    return tonumber(v) > x
  end
end

-- given a number, returns a function(y) which returns true if y < x
-- @param x a number
function seq.less_than(x)
  return function(v)
    return tonumber(v) < x
  end
end

-- given any value, return a function(y) which returns true if y == x
-- @param x a value
function seq.equal_to(x)
  if type(x) == "number" then
    return function(v)
      return tonumber(v) == x
    end
  else
    return function(v)
      return v == x
    end
  end
end

--- given a string, return a function(y) which matches y against the string.
-- @param s a string
function seq.matching(s)
  return function(v)
     return strfind(v,s)
  end
end

local nexti

--- sequence adaptor for a table.   Note that if any generic function is
-- passed a table, it will automatically use seq.list()
-- @param t a list-like table
-- @usage sum(list(t)) is the sum of all elements of t
-- @usage for x in list(t) do...end
function seq.list(t)
  assert_arg(1,t,'table')
  if not nexti then
    nexti = ipairs{}
  end
  local key,value = 0
  return function()
    key,value = nexti(t,key)
    return value
  end
end

--- return the keys of the table.
-- @param t an arbitrary table
-- @return iterator over keys
function seq.keys(t)
  assert_arg(1,t,'table')
  local key
  return function()
    key = next(t,key)
    return key
  end
end

local list = seq.list
local function default_iter(iter)
  if type(iter) == 'table' then return list(iter)
  else return iter end
end

seq.iter = default_iter

--- create an iterator over a numerical range. Like the standard Python function xrange.
-- @param start a number
-- @param finish a number greater than start
function seq.range(start,finish)
  local i = start - 1
  return function()
      i = i + 1
      if i > finish then return nil
      else return i end
  end
end

-- count the number of elements in the sequence which satisfy the predicate
-- @param iter a sequence
-- @param condn a predicate function (must return either true or false)
-- @param optional argument to be passed to predicate as second argument.
-- @return count
function seq.count(iter,condn,arg)
  local i = 0
  seq.foreach(iter,function(val)
        if condn(val,arg) then i = i + 1 end
  end)
  return i
end

--- return the minimum and the maximum value of the sequence.
-- @param iter a sequence
-- @return minimum value
-- @return maximum value
function seq.minmax(iter)
  local vmin,vmax = 1e70,-1e70
  for v in default_iter(iter) do
    v = tonumber(v)
    if v < vmin then vmin = v end
    if v > vmax then vmax = v end
  end
  return vmin,vmax
end

--- return the sum and element count of the sequence.
-- @param iter a sequence
-- @param fn an optional function to apply to the values
function seq.sum(iter,fn)
  local s = 0
  local i = 0
  for v in default_iter(iter) do
    if fn then v = fn(v) end
    s = s + v
    i = i + 1
  end
  return s,i
end

--- create a table from the sequence. (This will make the result a List.)
-- @param iter a sequence
-- @return a List
-- @usage copy(list(ls)) is equal to ls
-- @usage copy(list {1,2,3}) == List{1,2,3}
function seq.copy(iter)
    local res,k = {},1
    for v in default_iter(iter) do
        res[k] = v
        k = k + 1
    end
    setmetatable(res, require('pl.List'))
    return res
end

--- create a table of pairs from the double-valued sequence.
-- @param iter a double-valued sequence
-- @param i1 used to capture extra iterator values
-- @param i2 as with pairs & ipairs
-- @usage copy2(ipairs{10,20,30}) == {{1,10},{2,20},{3,30}}
-- @return a list-like table
function seq.copy2 (iter,i1,i2)
    local res,k = {},1
    for v1,v2 in iter,i1,i2 do
        res[k] = {v1,v2}
        k = k + 1
    end
    return res
end

--- create a table of 'tuples' from a multi-valued sequence.
-- A generalization of copy2 above
-- @param iter a multiple-valued sequence
-- @return a list-like table
function seq.copy_tuples (iter)
    iter = default_iter(iter)
    local res = {}
    local row = {iter()}
    while #row > 0 do
        tappend(res,row)
        row = {iter()}
    end
    return res
end

--- return an iterator of random numbers.
-- @param n the length of the sequence
-- @param l same as the first optional argument to math.random
-- @param u same as the second optional argument to math.random
-- @return a sequence
function seq.random(n,l,u)
  local rand
  assert(type(n) == 'number')
  if u then
     rand = function() return mrandom(l,u) end
  elseif l then
     rand = function() return mrandom(l) end
  else
     rand = mrandom
  end

  return function()
     if n == 0 then return nil
     else
       n = n - 1
       return rand()
     end
  end
end

--- return an iterator to the sorted elements of a sequence.
-- @param iter a sequence
-- @param comp an optional comparison function (comp(x,y) is true if x < y)
function seq.sort(iter,comp)
    local t = seq.copy(iter)
    tsort(t,comp)
    return list(t)
end

--- return an iterator which returns elements of two sequences.
-- @param iter1 a sequence
-- @param iter2 a sequence
-- @usage for x,y in seq.zip(ls1,ls2) do....end
function seq.zip(iter1,iter2)
    iter1 = default_iter(iter1)
    iter2 = default_iter(iter2)
    return function()
        return iter1(),iter2()
    end
end

--- Makes a table where the key/values are the values and value counts of the sequence.
-- This version works with 'hashable' values like strings and numbers.
-- `pl.tablex.count_map` is more general.
-- @param iter a sequence
-- @return a map-like table
-- @return a table
-- @see pl.tablex.count_map
function seq.count_map(iter)
    local t = {}
    local v
    for s in default_iter(iter) do
        v = t[s]
        if v then t[s] = v + 1
        else t[s] = 1 end
    end
    return setmetatable(t, require('pl.Map'))
end

-- given a sequence, return all the unique values in that sequence.
-- @param iter a sequence
-- @param returns_table true if we return a table, not a sequence
-- @return a sequence or a table; defaults to a sequence.
function seq.unique(iter,returns_table)
    local t = seq.count_map(iter)
    local res,k = {},1
    for key in pairs(t) do res[k] = key; k = k + 1 end
    table.sort(res)
    if returns_table then
        return res
    else
        return list(res)
    end
end

--- print out a sequence iter with a separator.
-- @param iter a sequence
-- @param sep the separator (default space)
-- @param nfields maximum number of values per line (default 7)
-- @param fmt optional format function for each value
function seq.printall(iter,sep,nfields,fmt)
  local write = io.write
  if not sep then sep = ' ' end
  if not nfields then
      if sep == '\n' then nfields = 1e30
      else nfields = 7 end
  end
  if fmt then
    local fstr = fmt
    fmt = function(v) return format(fstr,v) end
  end
  local k = 1
  for v in default_iter(iter) do
     if fmt then v = fmt(v) end
     if k < nfields then
       write(v,sep)
       k = k + 1
    else
       write(v,'\n')
       k = 1
    end
  end
  write '\n'
end

-- return an iterator running over every element of two sequences (concatenation).
-- @param iter1 a sequence
-- @param iter2 a sequence
function seq.splice(iter1,iter2)
  iter1 = default_iter(iter1)
  iter2 = default_iter(iter2)
  local iter = iter1
  return function()
    local ret = iter()
    if ret == nil then
      if iter == iter1 then
        iter = iter2
        return iter()
      else return nil end
   else
       return  ret
   end
 end
end

--- return a sequence where every element of a sequence has been transformed
-- by a function. If you don't supply an argument, then the function will
-- receive both values of a double-valued sequence, otherwise behaves rather like
-- tablex.map.
-- @param fn a function to apply to elements; may take two arguments
-- @param iter a sequence of one or two values
-- @param arg optional argument to pass to function.
function seq.map(fn,iter,arg)
    fn = function_arg(1,fn)
    iter = default_iter(iter)
    return function()
        local v1,v2 = iter()
        if v1 == nil then return nil end
        return fn(v1,arg or v2) or false
    end
end

--- filter a sequence using a predicate function.
-- @param iter a sequence of one or two values
-- @param pred a boolean function; may take two arguments
-- @param arg optional argument to pass to function.
function seq.filter (iter,pred,arg)
    pred = function_arg(2,pred)
    return function ()
        local v1,v2
        while true do
            v1,v2 = iter()
            if v1 == nil then return nil end
            if pred(v1,arg or v2) then return v1,v2 end
        end
    end
end

--- 'reduce' a sequence using a binary function.
-- @func fn a function of two arguments
-- @param iter a sequence
-- @param initval optional initial value
-- @usage seq.reduce(operator.add,seq.list{1,2,3,4}) == 10
-- @usage seq.reduce('-',{1,2,3,4,5}) == -13
function seq.reduce (fn,iter,initval)
   fn = function_arg(1,fn)
   iter = default_iter(iter)
   local val = initval or iter()
   if val == nil then return nil end
   for v in iter do
       val = fn(val,v)
   end
   return val
end

--- take the first n values from the sequence.
-- @param iter a sequence of one or two values
-- @param n number of items to take
-- @return a sequence of at most n items
function seq.take (iter,n)
    iter = default_iter(iter)
    return function()
        if n < 1 then return end
        local val1,val2 = iter()
        if not val1 then return end
        n = n - 1
        return val1,val2
    end
end

--- skip the first n values of a sequence
-- @param iter a sequence of one or more values
-- @param n number of items to skip
function seq.skip (iter,n)
    n = n or 1
    for i = 1,n do
        if iter() == nil then return list{} end
    end
    return iter
end

--- a sequence with a sequence count and the original value.
-- enum(copy(ls)) is a roundabout way of saying ipairs(ls).
-- @param iter a single or double valued sequence
-- @return sequence of (i,v), i = 1..n and v is from iter.
function seq.enum (iter)
    local i = 0
    iter = default_iter(iter)
    return function  ()
        local val1,val2 = iter()
        if not val1 then return end
        i = i + 1
        return i,val1,val2
    end
end

--- map using a named method over a sequence.
-- @param iter a sequence
-- @param name the method name
-- @param arg1 optional first extra argument
-- @param arg2 optional second extra argument
function seq.mapmethod (iter,name,arg1,arg2)
    iter = default_iter(iter)
    return function()
        local val = iter()
        if not val then return end
        local fn = val[name]
        if not fn then error(type(val).." does not have method "..name) end
        return fn(val,arg1,arg2)
    end
end

--- a sequence of (last,current) values from another sequence.
--  This will return S(i-1),S(i) if given S(i)
-- @param iter a sequence
function seq.last (iter)
    iter = default_iter(iter)
    local val, l = iter(), nil
    if val == nil then return list{} end
    return function ()
        val,l = iter(),val
        if val == nil then return nil end
        return val,l
    end
end

--- call the function on each element of the sequence.
-- @param iter a sequence with up to 3 values
-- @param fn a function
function seq.foreach(iter,fn)
    fn = function_arg(2,fn)
    for i1,i2,i3 in default_iter(iter) do fn(i1,i2,i3) end
end

---------------------- Sequence Adapters ---------------------

local SMT

local function SW (iter,...)
    if callable(iter) then
        return setmetatable({iter=iter},SMT)
    else
        return iter,...
    end
end


-- can't directly look these up in seq because of the wrong argument order...
local map,reduce,mapmethod = seq.map, seq.reduce, seq.mapmethod
local overrides = {
    map = function(self,fun,arg)
        return map(fun,self,arg)
    end,
    reduce = function(self,fun,initval)
        return reduce(fun,self,initval)
    end
}

SMT = {
    __index = function (tbl,key)
        local fn = overrides[key] or seq[key]
        if fn then
            return function(sw,...) return SW(fn(sw.iter,...)) end
        else
            return function(sw,...) return SW(mapmethod(sw.iter,key,...)) end
        end
    end,
    __call = function (sw)
        return sw.iter()
    end,
}

setmetatable(seq,{
    __call = function(tbl,iter,extra)
        if not callable(iter) then
            if type(iter) == 'table' then iter = seq.list(iter)
            else return iter
            end
        end
        if extra then
            return setmetatable({iter=function()
                return iter(extra)
            end},SMT)
        else
            return setmetatable({iter=iter},SMT)
        end
    end
})

--- create a wrapped iterator over all lines in the file.
-- @param f either a filename, file-like object, or 'STDIN' (for standard input)
-- @param ... for Lua 5.2 only, optional format specifiers, as in `io.read`.
-- @return a sequence wrapper
function seq.lines (f,...)
    local iter,obj
    if f == 'STDIN' then
        f = io.stdin
    elseif type(f) == 'string' then
        iter,obj = io.lines(f,...)
    elseif not f.read then
        error("Pass either a string or a file-like object",2)
    end
    if not iter then
        iter,obj = f:lines(...)
    end
    if obj then -- LuaJIT version returns a function operating on a file
        local lines,file = iter,obj
        iter = function() return lines(file) end
    end
    return SW(iter)
end

function seq.import ()
    debug.setmetatable(function() end,{
        __index = function(tbl,key)
            local s = overrides[key] or seq[key]
            if s then return s
            else
                return function(s,...) return seq.mapmethod(s,key,...) end
            end
        end
    })
end

return seq

end,

["pl.Set"] = function()
--------------------
-- Module: 'pl.Set'
--------------------
--- A Set class.
--
--     > Set = require 'pl.Set'
--     > = Set{'one','two'} == Set{'two','one'}
--     true
--     > fruit = Set{'apple','banana','orange'}
--     > = fruit['banana']
--     true
--     > = fruit['hazelnut']
--     nil
--     > colours = Set{'red','orange','green','blue'}
--     > = fruit,colours
--     [apple,orange,banana]   [blue,green,orange,red]
--     > = fruit+colours
--     [blue,green,apple,red,orange,banana]
--     [orange]
--     > more_fruits = fruit + 'apricot'
--     > = fruit*colours
--    > =  more_fruits, fruit
--    [banana,apricot,apple,orange]	[banana,apple,orange]
--
-- Dependencies: `pl.utils`, `pl.tablex`, `pl.class`, `pl.Map`, (`pl.List` if __tostring is used)
-- @classmod pl.Set

local tablex = require 'pl.tablex'
local utils = require 'pl.utils'
local array_tostring, concat = utils.array_tostring, table.concat
local merge,difference = tablex.merge,tablex.difference
local Map = require 'pl.Map'
local class = require 'pl.class'
local stdmt = utils.stdmt
local Set = stdmt.Set

-- the Set class --------------------
class(Map,nil,Set)

-- note: Set has _no_ methods!
Set.__index = nil

local function makeset (t)
    return setmetatable(t,Set)
end

--- create a set. <br>
-- @param t may be a Set, Map or list-like table.
-- @class function
-- @name Set
function Set:_init (t)
    t = t or {}
    local mt = getmetatable(t)
    if mt == Set or mt == Map then
        for k in pairs(t) do self[k] = true end
    else
        for _,v in ipairs(t) do self[v] = true end
    end
end

--- string representation of a set.
-- @within metamethods
function Set:__tostring ()
    return '['..concat(array_tostring(Set.values(self)),',')..']'
end

--- get a list of the values in a set.
-- @param self a Set
-- @function Set.values
-- @return a list
Set.values = Map.keys

--- map a function over the values of a set.
-- @param self a Set
-- @param fn a function
-- @param ... extra arguments to pass to the function.
-- @return a new set
function Set.map (self,fn,...)
    fn = utils.function_arg(1,fn)
    local res = {}
    for k in pairs(self) do
        res[fn(k,...)] = true
    end
    return makeset(res)
end

--- union of two sets (also +).
-- @param self a Set
-- @param set another set
-- @return a new set
function Set.union (self,set)
    return merge(self,set,true)
end

--- modifies '+' operator to allow addition of non-Set elements
--- Preserves +/- semantics - does not modify first argument.
local function setadd(self,other)
    local mt = getmetatable(other)
    if mt == Set or mt == Map then
        return Set.union(self,other)
    else
        local new = Set(self)
        new[other] = true
        return new
    end
end

--- union of sets.
-- @within metamethods
-- @function Set.__add

Set.__add = setadd

--- intersection of two sets (also *).
-- @param self a Set
-- @param set another set
-- @return a new set
-- @usage
-- > s = Set{10,20,30}
-- > t = Set{20,30,40}
-- > = t
-- [20,30,40]
-- > = Set.intersection(s,t)
-- [30,20]
-- > = s*t
-- [30,20]

function Set.intersection (self,set)
    return merge(self,set,false)
end

--- intersection of sets.
-- @within metamethods
-- @function Set.__mul
Set.__mul = Set.intersection

--- new set with elements in the set that are not in the other (also -).
-- @param self a Set
-- @param set another set
-- @return a new set
function Set.difference (self,set)
    return difference(self,set,false)
end

--- modifies "-" operator to remove non-Set values from set.
--- Preserves +/- semantics - does not modify first argument.
local function setminus (self,other)
    local mt = getmetatable(other)
    if mt == Set or mt == Map then
        return Set.difference(self,other)
    else
        local new = Set(self)
        new[other] = nil
        return new
    end
end

--- difference of sets.
-- @within metamethods
-- @function Set.__sub
Set.__sub = setminus

-- a new set with elements in _either_ the set _or_ other but not both (also ^).
-- @param self a Set
-- @param set another set
-- @return a new set
function Set.symmetric_difference (self,set)
    return difference(self,set,true)
end

--- symmetric difference of sets.
-- @within metamethods
-- @function Set.__pow
Set.__pow = Set.symmetric_difference

--- is the first set a subset of the second (also <)?.
-- @param self a Set
-- @param set another set
-- @return true or false
function Set.issubset (self,set)
    for k in pairs(self) do
        if not set[k] then return false end
    end
    return true
end

--- first set subset of second?
-- @within metamethods
-- @function Set.__lt
Set.__lt = Set.issubset

--- is the set empty?.
-- @param self a Set
-- @return true or false
function Set.isempty (self)
    return next(self) == nil
end

--- are the sets disjoint? (no elements in common).
-- Uses naive definition, i.e. that intersection is empty
-- @param s1 a Set
-- @param s2 another set
-- @return true or false
function Set.isdisjoint (s1,s2)
    return Set.isempty(Set.intersection(s1,s2))
end

--- size of this set (also # for 5.2).
-- @param s a Set
-- @return size
-- @function Set.len
Set.len = tablex.size

--- cardinality of set (5.2).
-- @within metamethods
-- @function Set.__len
Set.__len = Set.len

--- equality between sets.
-- @within metamethods
function Set.__eq (s1,s2)
    return Set.issubset(s1,s2) and Set.issubset(s2,s1)
end

return Set

end,

["pl.sip"] = function()
--------------------
-- Module: 'pl.sip'
--------------------
--- Simple Input Patterns (SIP).
-- SIP patterns start with '$', then a
-- one-letter type, and then an optional variable in curly braces.
--
--    sip.match('$v=$q','name="dolly"',res)
--    ==> res=={'name','dolly'}
--    sip.match('($q{first},$q{second})','("john","smith")',res)
--    ==> res=={second='smith',first='john'}
--
-- Type names:
--
--    v     identifier
--    i     integer
--    f     floating-point
--    q     quoted string
--    ([{<  match up to closing bracket
--
-- See @{08-additional.md.Simple_Input_Patterns|the Guide}
--
-- @module pl.sip

local loadstring = rawget(_G,'loadstring') or load
local unpack = rawget(_G,'unpack') or rawget(table,'unpack')

local append,concat = table.insert,table.concat
local ipairs,type = ipairs,type
local io,_G = io,_G
local print,rawget = print,rawget

local patterns = {
    FLOAT = '[%+%-%d]%d*%.?%d*[eE]?[%+%-]?%d*',
    INTEGER = '[+%-%d]%d*',
    IDEN = '[%a_][%w_]*',
    OPTION = '[%a_][%w_%-]*',
}

local function assert_arg(idx,val,tp)
    if type(val) ~= tp then
        error("argument "..idx.." must be "..tp, 2)
    end
end

local sip = {}

local brackets = {['<'] = '>', ['('] = ')', ['{'] = '}', ['['] = ']' }
local stdclasses = {a=1,c=0,d=1,l=1,p=0,u=1,w=1,x=1,s=0}

local function group(s)
    return '('..s..')'
end

-- escape all magic characters except $, which has special meaning
-- Also, un-escape any characters after $, so $( and $[ passes through as is.
local function escape (spec)
    return (spec:gsub('[%-%.%+%[%]%(%)%^%%%?%*]','%%%0'):gsub('%$%%(%S)','$%1'))
end

-- Most spaces within patterns can match zero or more spaces.
-- Spaces between alphanumeric characters or underscores or between
-- patterns that can match these characters, however, must match at least
-- one space. Otherwise '$v $v' would match 'abcd' as {'abc', 'd'}.
-- This function replaces continuous spaces within a pattern with either
-- '%s*' or '%s+' according to this rule. The pattern has already
-- been stripped of pattern names by now.
local function compress_spaces(patt)
    return (patt:gsub("()%s+()", function(i1, i2)
        local before = patt:sub(i1 - 2, i1 - 1)
        if before:match('%$[vifadxlu]') or before:match('^[^%$]?[%w_]$') then
            local after = patt:sub(i2, i2 + 1)
            if after:match('%$[vifadxlu]') or after:match('^[%w_]') then
                return '%s+'
            end
        end
        return '%s*'
    end))
end

local pattern_map = {
  v = group(patterns.IDEN),
  i = group(patterns.INTEGER),
  f = group(patterns.FLOAT),
  o = group(patterns.OPTION),
  r = '(%S.*)',
  p = '([%a]?[:]?[\\/%.%w_]+)'
}

function sip.custom_pattern(flag,patt)
    pattern_map[flag] = patt
end

--- convert a SIP pattern into the equivalent Lua string pattern.
-- @param spec a SIP pattern
-- @param options a table; only the <code>at_start</code> field is
-- currently meaningful and ensures that the pattern is anchored
-- at the start of the string.
-- @return a Lua string pattern.
function sip.create_pattern (spec,options)
    assert_arg(1,spec,'string')
    local fieldnames,fieldtypes = {},{}

    if type(spec) == 'string' then
        spec = escape(spec)
    else
        local res = {}
        for i,s in ipairs(spec) do
            res[i] = escape(s)
        end
        spec = concat(res,'.-')
    end

    local kount = 1

    local function addfield (name,type)
        name = name or kount
        append(fieldnames,name)
        fieldtypes[name] = type
        kount = kount + 1
    end

    local named_vars = spec:find('{%a+}')

    if options and options.at_start then
        spec = '^'..spec
    end
    if spec:sub(-1,-1) == '$' then
        spec = spec:sub(1,-2)..'$r'
        if named_vars then spec = spec..'{rest}' end
    end

    local names

    if named_vars then
        names = {}
        spec = spec:gsub('{(%a+)}',function(name)
            append(names,name)
            return ''
        end)
    end
    spec = compress_spaces(spec)

    local k = 1
    local err
    local r = (spec:gsub('%$%S',function(s)
        local type,name
        type = s:sub(2,2)
        if names then name = names[k]; k=k+1 end
        -- this kludge is necessary because %q generates two matches, and
        -- we want to ignore the first. Not a problem for named captures.
        if not names and type == 'q' then
            addfield(nil,'Q')
        else
            addfield(name,type)
        end
        local res
        if pattern_map[type] then
            res = pattern_map[type]
        elseif type == 'q' then
            -- some Lua pattern matching voodoo; we want to match '...' as
            -- well as "...", and can use the fact that %n will match a
            -- previous capture. Adding the extra field above comes from needing
            -- to accommodate the extra spurious match (which is either ' or ")
            addfield(name,type)
            res = '(["\'])(.-)%'..(kount-2)
        else
            local endbracket = brackets[type]
            if endbracket then
                res = '(%b'..type..endbracket..')'
            elseif stdclasses[type] or stdclasses[type:lower()] then
                res = '(%'..type..'+)'
            else
                err = "unknown format type or character class"
            end
        end
        return res
    end))

    if err then
        return nil,err
    else
        return r,fieldnames,fieldtypes
    end
end


local function tnumber (s)
    return s == 'd' or s == 'i' or s == 'f'
end

function sip.create_spec_fun(spec,options)
    local fieldtypes,fieldnames
    local ls = {}
    spec,fieldnames,fieldtypes = sip.create_pattern(spec,options)
    if not spec then return spec,fieldnames end
    local named_vars = type(fieldnames[1]) == 'string'
    for i = 1,#fieldnames do
        append(ls,'mm'..i)
    end
    ls[1] = ls[1] or "mm1" -- behave correctly if there are no patterns
    local fun = ('return (function(s,res)\n\tlocal %s = s:match(%q)\n'):format(concat(ls,','),spec)
    fun = fun..'\tif not mm1 then return false end\n'
    local k=1
    for i,f in ipairs(fieldnames) do
        if f ~= '_' then
            local var = 'mm'..i
            if tnumber(fieldtypes[f]) then
                var = 'tonumber('..var..')'
            elseif brackets[fieldtypes[f]] then
                var = var..':sub(2,-2)'
            end
            if named_vars then
                fun = ('%s\tres.%s = %s\n'):format(fun,f,var)
            else
                if fieldtypes[f] ~= 'Q' then -- we skip the string-delim capture
                    fun = ('%s\tres[%d] = %s\n'):format(fun,k,var)
                    k = k + 1
                end
            end
        end
    end
    return fun..'\treturn true\nend)\n', named_vars
end

--- convert a SIP pattern into a matching function.
-- The returned function takes two arguments, the line and an empty table.
-- If the line matched the pattern, then this function returns true
-- and the table is filled with field-value pairs.
-- @param spec a SIP pattern
-- @param options optional table; {at_start=true} ensures that the pattern
-- is anchored at the start of the string.
-- @return a function if successful, or nil,error
function sip.compile(spec,options)
    assert_arg(1,spec,'string')
    local fun,names = sip.create_spec_fun(spec,options)
    if not fun then return nil,names end
    if rawget(_G,'_DEBUG') then print(fun) end
    local chunk,err = loadstring(fun,'tmp')
    if err then return nil,err end
    return chunk(),names
end

local cache = {}

--- match a SIP pattern against a string.
-- @param spec a SIP pattern
-- @param line a string
-- @param res a table to receive values
-- @param options (optional) option table
-- @return true or false
function sip.match (spec,line,res,options)
    assert_arg(1,spec,'string')
    assert_arg(2,line,'string')
    assert_arg(3,res,'table')
    if not cache[spec] then
        cache[spec] = sip.compile(spec,options)
    end
    return cache[spec](line,res)
end

--- match a SIP pattern against the start of a string.
-- @param spec a SIP pattern
-- @param line a string
-- @param res a table to receive values
-- @return true or false
function sip.match_at_start (spec,line,res)
    return sip.match(spec,line,res,{at_start=true})
end

--- given a pattern and a file object, return an iterator over the results
-- @param spec a SIP pattern
-- @param f a file-like object.
function sip.fields (spec,f)
    assert_arg(1,spec,'string')
    if not f then return nil,"no file object" end
    local fun,err = sip.compile(spec)
    if not fun then return nil,err end
    local res = {}
    return function()
        while true do
            local line = f:read()
            if not line then return end
            if fun(line,res) then
                local values = res
                res = {}
                return unpack(values)
            end
        end
    end
end

local read_patterns = {}

--- register a match which will be used in the read function.
-- @string spec a SIP pattern
-- @func fun a function to be called with the results of the match
-- @see read
function sip.pattern (spec,fun)
    assert_arg(1,spec,'string')
    local pat,named = sip.compile(spec)
    append(read_patterns,{pat=pat,named=named,callback=fun})
end

--- enter a loop which applies all registered matches to the input file.
-- @param f a file-like object
-- @array matches optional list of `{spec,fun}` pairs, as for `pattern` above.
function sip.read (f,matches)
    local owned,err
    if not f then return nil,"no file object" end
    if type(f) == 'string' then
        f,err = io.open(f)
        if not f then return nil,err end
        owned = true
    end
    if matches then
        for _,p in ipairs(matches) do
            sip.pattern(p[1],p[2])
        end
    end
    local res = {}
    for line in f:lines() do
        for _,item in ipairs(read_patterns) do
            if item.pat(line,res) then
                if item.callback then
                    if item.named then
                        item.callback(res)
                    else
                        item.callback(unpack(res))
                    end
                end
                res = {}
                break
            end
        end
    end
    if owned then f:close() end
end

return sip

end,

["pl.strict"] = function()
--------------------
-- Module: 'pl.strict'
--------------------
--- Checks uses of undeclared global variables.
-- All global variables must be 'declared' through a regular assignment
-- (even assigning `nil` will do) in a main chunk before being used
-- anywhere or assigned to inside a function. Existing metatables `__newindex` and `__index`
-- metamethods are respected.
--
-- You can set any table to have strict behaviour using `strict.module`. Creating a new
-- module with `strict.closed_module` makes the module immune to monkey-patching, if
-- you don't wish to encourage monkey business.
--
-- If the global `PENLIGHT_NO_GLOBAL_STRICT` is defined, then this module won't make the
-- global environment strict - if you just want to explicitly set table strictness.
--
-- @module pl.strict

require 'debug' -- for Lua 5.2
local getinfo, error, rawset, rawget = debug.getinfo, error, rawset, rawget
local strict = {}

local function what ()
    local d = getinfo(3, "S")
    return d and d.what or "C"
end

--- make an existing table strict.
-- @string[opt] name name of table
-- @tab[opt] mod the table to protect - if `nil` then we'll return a new table
-- @tab[opt] predeclared - table of variables that are to be considered predeclared.
-- @return the given table, or a new table
-- @usage
-- local M = { hello = "world" }
-- strict.module ("Awesome_Module", M, {
--   Lua = true,  -- defines allowed keys
-- })
--
-- assert(M.hello == "world")
-- assert(M.Lua == nil)       -- access allowed, but has no value yet
-- M.Lua = "Rocks"
-- assert(M.Lua == "Rocks")
-- M.not_allowed = "bad boy"  -- throws an error
function strict.module (name,mod,predeclared)
    local mt, old_newindex, old_index, old_index_type, global
    if predeclared then
        global = predeclared.__global
    end
    if type(mod) == 'table' then
        mt = getmetatable(mod)
        if mt and rawget(mt,'__declared') then return end -- already patched...
    else
        mod = {}
    end
    if mt == nil then
        mt = {}
        setmetatable(mod, mt)
    else
        old_newindex = mt.__newindex
        old_index = mt.__index
        old_index_type = type(old_index)
    end
    mt.__declared = predeclared or {}
    mt.__newindex = function(t, n, v)
        if old_newindex then
            old_newindex(t, n, v)
            if rawget(t,n)~=nil then return end
        end
        if not mt.__declared[n] then
            if global then
                local w = what()
                if w ~= "main" and w ~= "C" then
                    error("assign to undeclared global '"..n.."'", 2)
                end
            end
            mt.__declared[n] = true
        end
        rawset(t, n, v)
    end
    mt.__index = function(t,n)
        if not mt.__declared[n] and what() ~= "C" then
            if old_index then
                if old_index_type == "table" then
                    local fallback = old_index[n]
                    if fallback ~= nil then
                        return fallback
                    end
                else
                    local res = old_index(t, n)
                    if res ~= nil then
                        return res
                    end
                end
            end
            local msg = "variable '"..n.."' is not declared"
            if name then
                msg = msg .. " in '"..tostring(name).."'"
            end
            error(msg, 2)
        end
        return rawget(t, n)
    end
    return mod
end

--- make all tables in a table strict.
-- So `strict.make_all_strict(_G)` prevents monkey-patching
-- of any global table
-- @tab T the table containing the tables to protect. Table `T` itself will NOT be protected.
function strict.make_all_strict (T)
    for k,v in pairs(T) do
        if type(v) == 'table' and v ~= T then
            strict.module(k,v)
        end
    end
end

--- make a new module table which is closed to further changes.
-- @tab mod module table
-- @string name module name
function strict.closed_module (mod,name)
    -- No clue to what this is useful for? see tests
    -- Deprecate this and remove???
    local M = {}
    mod = mod or {}
    local mt = getmetatable(mod)
    if not mt then
        mt = {}
        setmetatable(mod,mt)
    end
    mt.__newindex = function(t,k,v)
        M[k] = v
    end
    return strict.module(name,M)
end

if not rawget(_G,'PENLIGHT_NO_GLOBAL_STRICT') then
    strict.module(nil,_G,{_PROMPT=true,_PROMPT2=true,__global=true})
end

return strict

end,

["pl.stringio"] = function()
--------------------
-- Module: 'pl.stringio'
--------------------
--- Reading and writing strings using file-like objects. <br>
--
--    f = stringio.open(text)
--    l1 = f:read()  -- read first line
--    n,m = f:read ('*n','*n') -- read two numbers
--    for line in f:lines() do print(line) end -- iterate over all lines
--    f = stringio.create()
--    f:write('hello')
--    f:write('dolly')
--    assert(f:value(),'hellodolly')
--
-- See  @{03-strings.md.File_style_I_O_on_Strings|the Guide}.
-- @module pl.stringio

local unpack = rawget(_G,'unpack') or rawget(table,'unpack')
local tonumber = tonumber
local concat,append = table.concat,table.insert

local stringio = {}

-- Writer class
local SW = {}
SW.__index = SW

local function xwrite(self,...)
    local args = {...} --arguments may not be nil!
    for i = 1, #args do
        append(self.tbl,args[i])
    end
end

function SW:write(arg1,arg2,...)
    if arg2 then
        xwrite(self,arg1,arg2,...)
    else
        append(self.tbl,arg1)
    end
end

function SW:writef(fmt,...)
    self:write(fmt:format(...))
end

function SW:value()
    return concat(self.tbl)
end

function SW:__tostring()
    return self:value()
end

function SW:close() -- for compatibility only
end

function SW:seek()
end

-- Reader class
local SR = {}
SR.__index = SR

function SR:_read(fmt)
    local i,str = self.i,self.str
    local sz = #str
    if i > sz then return nil end
    local res
    if fmt == '*l' or fmt == '*L' then
        local idx = str:find('\n',i) or (sz+1)
        res = str:sub(i,fmt == '*l' and idx-1 or idx)
        self.i = idx+1
    elseif fmt == '*a' then
        res = str:sub(i)
        self.i = sz
    elseif fmt == '*n' then
        local _,i2,idx
        _,idx = str:find ('%s*%d+',i)
        _,i2 = str:find ('^%.%d+',idx+1)
        if i2 then idx = i2 end
        _,i2 = str:find ('^[eE][%+%-]*%d+',idx+1)
        if i2 then idx = i2 end
        local val = str:sub(i,idx)
        res = tonumber(val)
        self.i = idx+1
    elseif type(fmt) == 'number' then
        res = str:sub(i,i+fmt-1)
        self.i = i + fmt
    else
        error("bad read format",2)
    end
    return res
end

function SR:read(...)
    if select('#',...) == 0 then
        return self:_read('*l')
    else
        local res, fmts = {},{...}
        for i = 1, #fmts do
            res[i] = self:_read(fmts[i])
        end
        return unpack(res)
    end
end

function SR:seek(whence,offset)
    local base
    whence = whence or 'cur'
    offset = offset or 0
    if whence == 'set' then
        base = 1
    elseif whence == 'cur' then
        base = self.i
    elseif whence == 'end' then
        base = #self.str
    end
    self.i = base + offset
    return self.i
end

function SR:lines(...)
    local n, args = select('#',...)
    if n > 0 then
        args = {...}
    end
    return function()
        if n == 0 then
            return self:_read '*l'
        else
            return self:read(unpack(args))
        end
    end
end

function SR:close() -- for compatibility only
end

--- create a file-like object which can be used to construct a string.
-- The resulting object has an extra `value()` method for
-- retrieving the string value.  Implements `file:write`, `file:seek`, `file:lines`,
-- plus an extra `writef` method which works like `utils.printf`.
-- @usage f = create(); f:write('hello, dolly\n'); print(f:value())
function stringio.create()
    return setmetatable({tbl={}},SW)
end

--- create a file-like object for reading from a given string.
-- Implements `file:read`.
-- @string s The input string.
-- @usage fs = open '20 10'; x,y = f:read ('*n','*n'); assert(x == 20 and y == 10)
function stringio.open(s)
    return setmetatable({str=s,i=1},SR)
end

function stringio.lines(s,...)
    return stringio.open(s):lines(...)
end

return stringio

end,

["pl.stringx"] = function()
--------------------
-- Module: 'pl.stringx'
--------------------
--- Python-style extended string library.
--
-- see 3.6.1 of the Python reference.
-- If you want to make these available as string methods, then say
-- `stringx.import()` to bring them into the standard `string` table.
--
-- See @{03-strings.md|the Guide}
--
-- Dependencies: `pl.utils`, `pl.types`
-- @module pl.stringx
local utils = require 'pl.utils'
local is_callable = require 'pl.types'.is_callable
local string = string
local find = string.find
local type,setmetatable,ipairs = type,setmetatable,ipairs
local error = error
local gsub = string.gsub
local rep = string.rep
local sub = string.sub
local reverse = string.reverse
local concat = table.concat
local append = table.insert
local remove = table.remove
local escape = utils.escape
local ceil, max = math.ceil, math.max
local assert_arg,usplit = utils.assert_arg,utils.split
local lstrip
local unpack = utils.unpack
local pack = utils.pack

local function assert_string (n,s)
    assert_arg(n,s,'string')
end

local function non_empty(s)
    return #s > 0
end

local function assert_nonempty_string(n,s)
    assert_arg(n,s,'string',non_empty,'must be a non-empty string')
end

local function makelist(l)
    return setmetatable(l, require('pl.List'))
end

local stringx = {}

------------------
-- String Predicates
-- @section predicates

--- does s only contain alphabetic characters?
-- @string s a string
function stringx.isalpha(s)
    assert_string(1,s)
    return find(s,'^%a+$') == 1
end

--- does s only contain digits?
-- @string s a string
function stringx.isdigit(s)
    assert_string(1,s)
    return find(s,'^%d+$') == 1
end

--- does s only contain alphanumeric characters?
-- @string s a string
function stringx.isalnum(s)
    assert_string(1,s)
    return find(s,'^%w+$') == 1
end

--- does s only contain whitespace?
-- Matches on pattern '%s' so matches space, newline, tabs, etc.
-- @string s a string
function stringx.isspace(s)
    assert_string(1,s)
    return find(s,'^%s+$') == 1
end

--- does s only contain lower case characters?
-- @string s a string
function stringx.islower(s)
    assert_string(1,s)
    return find(s,'^[%l%s]+$') == 1
end

--- does s only contain upper case characters?
-- @string s a string
function stringx.isupper(s)
    assert_string(1,s)
    return find(s,'^[%u%s]+$') == 1
end

local function raw_startswith(s, prefix)
    return find(s,prefix,1,true) == 1
end

local function raw_endswith(s, suffix)
    return #s >= #suffix and find(s, suffix, #s-#suffix+1, true) and true or false
end

local function test_affixes(s, affixes, fn)
    if type(affixes) == 'string' then
        return fn(s,affixes)
    elseif type(affixes) == 'table' then
        for _,affix in ipairs(affixes) do
            if fn(s,affix) then return true end
        end
        return false
    else
        error(("argument #2 expected a 'string' or a 'table', got a '%s'"):format(type(affixes)))
    end
end

--- does s start with prefix or one of prefixes?
-- @string s a string
-- @param prefix a string or an array of strings
function stringx.startswith(s,prefix)
    assert_string(1,s)
    return test_affixes(s,prefix,raw_startswith)
end

--- does s end with suffix or one of suffixes?
-- @string s a string
-- @param suffix a string or an array of strings
function stringx.endswith(s,suffix)
    assert_string(1,s)
    return test_affixes(s,suffix,raw_endswith)
end

--- Strings and Lists
-- @section lists

--- concatenate the strings using this string as a delimiter.
-- Note that the arguments are reversed from `string.concat`.
-- @string s the string
-- @param seq a table of strings or numbers
-- @usage stringx.join(' ', {1,2,3}) == '1 2 3'
function stringx.join(s,seq)
    assert_string(1,s)
    return concat(seq,s)
end

--- Split a string into a list of lines.
-- `"\r"`, `"\n"`, and `"\r\n"` are considered line ends.
-- They are not included in the lines unless `keepends` is passed.
-- Terminal line end does not produce an extra line.
-- Splitting an empty string results in an empty list.
-- @string s the string.
-- @bool[opt] keep_ends include line ends.
-- @return List of lines
function stringx.splitlines(s, keep_ends)
    assert_string(1, s)
    local res = {}
    local pos = 1
    while true do
        local line_end_pos = find(s, '[\r\n]', pos)
        if not line_end_pos then
            break
        end

        local line_end = sub(s, line_end_pos, line_end_pos)
        if line_end == '\r' and sub(s, line_end_pos + 1, line_end_pos + 1) == '\n' then
            line_end = '\r\n'
        end

        local line = sub(s, pos, line_end_pos - 1)
        if keep_ends then
            line = line .. line_end
        end
        append(res, line)

        pos = line_end_pos + #line_end
    end

    if pos <= #s then
        append(res, sub(s, pos))
    end
    return makelist(res)
end

--- split a string into a list of strings using a delimiter.
-- @function split
-- @string s the string
-- @string[opt] re a delimiter (defaults to whitespace)
-- @int[opt] n maximum number of results
-- @return List
-- @usage #(stringx.split('one two')) == 2
-- @usage stringx.split('one,two,three', ',') == List{'one','two','three'}
-- @usage stringx.split('one,two,three', ',', 2) == List{'one','two,three'}
function stringx.split(s,re,n)
    assert_string(1,s)
    local plain = true
    if not re then -- default spaces
        s = lstrip(s)
        plain = false
    end
    local res = usplit(s,re,plain,n)
    if re and re ~= '' and
       find(s,re,-#re,true) and
       (n or math.huge) > #res then
        res[#res+1] = ""
    end
    return makelist(res)
end

--- replace all tabs in s with tabsize spaces. If not specified, tabsize defaults to 8.
-- Tab stops will be honored.
-- @string s the string
-- @int tabsize[opt=8] number of spaces to expand each tab
-- @return expanded string
-- @usage stringx.expandtabs('\tone,two,three', 4)   == '    one,two,three'
-- @usage stringx.expandtabs('  \tone,two,three', 4) == '    one,two,three'
function stringx.expandtabs(s,tabsize)
  assert_string(1,s)
  tabsize = tabsize or 8
  return (s:gsub("([^\t\r\n]*)\t", function(before_tab)
      if tabsize == 0 then
        return before_tab
      else
        return before_tab .. (" "):rep(tabsize - #before_tab % tabsize)
      end
    end))
end

--- Finding and Replacing
-- @section find

local function _find_all(s,sub,first,last,allow_overlap)
    first = first or 1
    last = last or #s
    if sub == '' then return last+1,last-first+1 end
    local i1,i2 = find(s,sub,first,true)
    local res
    local k = 0
    while i1 do
        if last and i2 > last then break end
        res = i1
        k = k + 1
        if allow_overlap then
            i1,i2 = find(s,sub,i1+1,true)
        else
            i1,i2 = find(s,sub,i2+1,true)
        end
    end
    return res,k
end

--- find index of first instance of sub in s from the left.
-- @string s the string
-- @string sub substring
-- @int[opt] first first index
-- @int[opt] last last index
-- @return start index, or nil if not found
function stringx.lfind(s,sub,first,last)
    assert_string(1,s)
    assert_string(2,sub)
    local i1, i2 = find(s,sub,first,true)

    if i1 and (not last or i2 <= last) then
        return i1
    else
        return nil
    end
end

--- find index of first instance of sub in s from the right.
-- @string s the string
-- @string sub substring
-- @int[opt] first first index
-- @int[opt] last last index
-- @return start index, or nil if not found
function stringx.rfind(s,sub,first,last)
    assert_string(1,s)
    assert_string(2,sub)
    return (_find_all(s,sub,first,last,true))
end

--- replace up to n instances of old by new in the string s.
-- If n is not present, replace all instances.
-- @string s the string
-- @string old the target substring
-- @string new the substitution
-- @int[opt] n optional maximum number of substitutions
-- @return result string
function stringx.replace(s,old,new,n)
    assert_string(1,s)
    assert_string(2,old)
    assert_string(3,new)
    return (gsub(s,escape(old),new:gsub('%%','%%%%'),n))
end

--- count all instances of substring in string.
-- @string s the string
-- @string sub substring
-- @bool[opt] allow_overlap allow matches to overlap
-- @usage
-- assert(stringx.count('banana', 'ana') == 1)
-- assert(stringx.count('banana', 'ana', true) == 2)
function stringx.count(s,sub,allow_overlap)
    assert_string(1,s)
    local _,k = _find_all(s,sub,1,false,allow_overlap)
    return k
end

--- Stripping and Justifying
-- @section strip

local function _just(s,w,ch,left,right)
    local n = #s
    if w > n then
        if not ch then ch = ' ' end
        local f1,f2
        if left and right then
            local rn = ceil((w-n)/2)
            local ln = w - n - rn
            f1 = rep(ch,ln)
            f2 = rep(ch,rn)
        elseif right then
            f1 = rep(ch,w-n)
            f2 = ''
        else
            f2 = rep(ch,w-n)
            f1 = ''
        end
        return f1..s..f2
    else
        return s
    end
end

--- left-justify s with width w.
-- @string s the string
-- @int w width of justification
-- @string[opt=' '] ch padding character
-- @usage stringx.ljust('hello', 10, '*') == '*****hello'
function stringx.ljust(s,w,ch)
    assert_string(1,s)
    assert_arg(2,w,'number')
    return _just(s,w,ch,true,false)
end

--- right-justify s with width w.
-- @string s the string
-- @int w width of justification
-- @string[opt=' '] ch padding character
-- @usage stringx.rjust('hello', 10, '*') == 'hello*****'
function stringx.rjust(s,w,ch)
    assert_string(1,s)
    assert_arg(2,w,'number')
    return _just(s,w,ch,false,true)
end

--- center-justify s with width w.
-- @string s the string
-- @int w width of justification
-- @string[opt=' '] ch padding character
-- @usage stringx.center('hello', 10, '*') == '**hello***'
function stringx.center(s,w,ch)
    assert_string(1,s)
    assert_arg(2,w,'number')
    return _just(s,w,ch,true,true)
end

local function _strip(s,left,right,chrs)
    if not chrs then
        chrs = '%s'
    else
        chrs = '['..escape(chrs)..']'
    end
    local f = 1
    local t
    if left then
        local i1,i2 = find(s,'^'..chrs..'*')
        if i2 >= i1 then
            f = i2+1
        end
    end
    if right then
        if #s < 200 then
            local i1,i2 = find(s,chrs..'*$',f)
            if i2 >= i1 then
                t = i1-1
            end
        else
            local rs = reverse(s)
            local i1,i2 = find(rs, '^'..chrs..'*')
            if i2 >= i1 then
                t = -i2-1
            end
        end
    end
    return sub(s,f,t)
end

--- trim any characters on the left of s.
-- @string s the string
-- @string[opt='%s'] chrs default any whitespace character,
-- but can be a string of characters to be trimmed
function stringx.lstrip(s,chrs)
    assert_string(1,s)
    return _strip(s,true,false,chrs)
end
lstrip = stringx.lstrip

--- trim any characters on the right of s.
-- @string s the string
-- @string[opt='%s'] chrs default any whitespace character,
-- but can be a string of characters to be trimmed
function stringx.rstrip(s,chrs)
    assert_string(1,s)
    return _strip(s,false,true,chrs)
end

--- trim any characters on both left and right of s.
-- @string s the string
-- @string[opt='%s'] chrs default any whitespace character,
-- but can be a string of characters to be trimmed
-- @usage stringx.strip('  --== Hello ==--  ', "- =")  --> 'Hello'
function stringx.strip(s,chrs)
    assert_string(1,s)
    return _strip(s,true,true,chrs)
end

--- Partitioning Strings
-- @section partitioning

--- split a string using a pattern. Note that at least one value will be returned!
-- @string s the string
-- @string[opt='%s'] re a Lua string pattern (defaults to whitespace)
-- @return the parts of the string
-- @usage  a,b = line:splitv('=')
-- @see utils.splitv
function stringx.splitv(s,re)
    assert_string(1,s)
    return utils.splitv(s,re)
end

-- The partition functions split a string using a delimiter into three parts:
-- the part before, the delimiter itself, and the part afterwards
local function _partition(p,delim,fn)
    local i1,i2 = fn(p,delim)
    if not i1 or i1 == -1 then
        return p,'',''
    else
        if not i2 then i2 = i1 end
        return sub(p,1,i1-1),sub(p,i1,i2),sub(p,i2+1)
    end
end

--- partition the string using first occurance of a delimiter
-- @string s the string
-- @string ch delimiter (match as plain string, no patterns)
-- @return part before ch
-- @return ch
-- @return part after ch
-- @usage {stringx.partition('a,b,c', ','))} == {'a', ',', 'b,c'}
-- @usage {stringx.partition('abc', 'x'))} == {'abc', '', ''}
function stringx.partition(s,ch)
    assert_string(1,s)
    assert_nonempty_string(2,ch)
    return _partition(s,ch,stringx.lfind)
end

--- partition the string p using last occurance of a delimiter
-- @string s the string
-- @string ch delimiter (match as plain string, no patterns)
-- @return part before ch
-- @return ch
-- @return part after ch
-- @usage {stringx.rpartition('a,b,c', ','))} == {'a,b', ',', 'c'}
-- @usage {stringx.rpartition('abc', 'x'))} == {'', '', 'abc'}
function stringx.rpartition(s,ch)
    assert_string(1,s)
    assert_nonempty_string(2,ch)
    local a,b,c = _partition(s,ch,stringx.rfind)
    if a == s then -- no match found
        return c,b,a
    end
    return a,b,c
end

--- return the 'character' at the index.
-- @string s the string
-- @int idx an index (can be negative)
-- @return a substring of length 1 if successful, empty string otherwise.
function stringx.at(s,idx)
    assert_string(1,s)
    assert_arg(2,idx,'number')
    return sub(s,idx,idx)
end


--- Text handling
-- @section text


--- indent a multiline string.
-- @tparam string s the (multiline) string
-- @tparam integer n the size of the indent
-- @tparam[opt=' '] string ch the character to use when indenting
-- @return indented string
function stringx.indent (s,n,ch)
  assert_arg(1,s,'string')
  assert_arg(2,n,'number')
  local lines = usplit(s ,'\n')
  local prefix = string.rep(ch or ' ',n)
  for i, line in ipairs(lines) do
    lines[i] = prefix..line
  end
  return concat(lines,'\n')..'\n'
end


--- dedent a multiline string by removing any initial indent.
-- useful when working with [[..]] strings.
-- Empty lines are ignored.
-- @tparam string s the (multiline) string
-- @return a string with initial indent zero.
-- @usage
-- local s = dedent [[
--          One
--
--        Two
--
--      Three
-- ]]
-- assert(s == [[
--     One
--
--   Two
--
-- Three
-- ]])
function stringx.dedent (s)
  assert_arg(1,s,'string')
  local lst = usplit(s,'\n')
  if #lst>0 then
    local ind_size = math.huge
    for i, line in ipairs(lst) do
      local i1, i2 = lst[i]:find('^%s*[^%s]')
      if i1 and i2 < ind_size then
        ind_size = i2
      end
    end
    for i, line in ipairs(lst) do
      lst[i] = lst[i]:sub(ind_size, -1)
    end
  end
  return concat(lst,'\n')..'\n'
end



do
  local buildline = function(words, size, breaklong)
    -- if overflow is set, a word longer than size, will overflow the size
    -- otherwise it will be chopped in line-length pieces
    local line = {}
    if #words[1] > size then
      -- word longer than line
      if not breaklong then
        line[1] = words[1]
        remove(words, 1)
      else
        line[1] = words[1]:sub(1, size)
        words[1] = words[1]:sub(size + 1, -1)
      end
    else
      local len = 0
      while words[1] and (len + #words[1] <= size) or
            (len == 0 and #words[1] == size) do
        if words[1] ~= "" then
          line[#line+1] = words[1]
          len = len + #words[1] + 1
        end
        remove(words, 1)
      end
    end
    return stringx.strip(concat(line, " ")), words
  end

  --- format a paragraph into lines so that they fit into a line width.
  -- It will not break long words by default, so lines can be over the length
  -- to that extent.
  -- @tparam string s the string to format
  -- @tparam[opt=70] integer width the margin width
  -- @tparam[opt=false] boolean breaklong if truthy, words longer than the width given will be forced split.
  -- @return a list of lines (List object), use `fill` to return a string instead of a `List`.
  -- @see pl.List
  -- @see fill
  stringx.wrap = function(s, width, breaklong)
    s = s:gsub('\n',' ') -- remove line breaks
    s = stringx.strip(s) -- remove leading/trailing whitespace
    if s == "" then
      return { "" }
    end
    width = width or 70
    local out = {}
    local words = usplit(s, "%s")
    while words[1] do
      out[#out+1], words = buildline(words, width, breaklong)
    end
    return makelist(out)
  end
end

--- format a paragraph so that it fits into a line width.
-- @tparam string s the string to format
-- @tparam[opt=70] integer width the margin width
-- @tparam[opt=false] boolean breaklong if truthy, words longer than the width given will be forced split.
-- @return a string, use `wrap` to return a list of lines instead of a string.
-- @see wrap
function stringx.fill (s,width,breaklong)
  return concat(stringx.wrap(s,width,breaklong),'\n') .. '\n'
end

--- Template
-- @section Template


local function _substitute(s,tbl,safe)
  local subst
  if is_callable(tbl) then
    subst = tbl
  else
    function subst(f)
      local s = tbl[f]
      if not s then
        if safe then
          return f
        else
          error("not present in table "..f)
        end
      else
        return s
      end
    end
  end
  local res = gsub(s,'%${([%w_]+)}',subst)
  return (gsub(res,'%$([%w_]+)',subst))
end



local Template = {}
stringx.Template = Template
Template.__index = Template
setmetatable(Template, {
  __call = function(obj,tmpl)
    return Template.new(tmpl)
  end
})

--- Creates a new Template class.
-- This is a shortcut to `Template.new(tmpl)`.
-- @tparam string tmpl the template string
-- @function Template
-- @treturn Template
function Template.new(tmpl)
  assert_arg(1,tmpl,'string')
  local res = {}
  res.tmpl = tmpl
  setmetatable(res,Template)
  return res
end

--- substitute values into a template, throwing an error.
-- This will throw an error if no name is found.
-- @tparam table tbl a table of name-value pairs.
-- @return string with place holders substituted
function Template:substitute(tbl)
  assert_arg(1,tbl,'table')
  return _substitute(self.tmpl,tbl,false)
end

--- substitute values into a template.
-- This version just passes unknown names through.
-- @tparam table tbl a table of name-value pairs.
-- @return string with place holders substituted
function Template:safe_substitute(tbl)
  assert_arg(1,tbl,'table')
  return _substitute(self.tmpl,tbl,true)
end

--- substitute values into a template, preserving indentation. <br>
-- If the value is a multiline string _or_ a template, it will insert
-- the lines at the correct indentation. <br>
-- Furthermore, if a template, then that template will be substituted
-- using the same table.
-- @tparam table tbl a table of name-value pairs.
-- @return string with place holders substituted
function Template:indent_substitute(tbl)
  assert_arg(1,tbl,'table')
  if not self.strings then
    self.strings = usplit(self.tmpl,'\n')
  end

  -- the idea is to substitute line by line, grabbing any spaces as
  -- well as the $var. If the value to be substituted contains newlines,
  -- then we split that into lines and adjust the indent before inserting.
  local function subst(line)
    return line:gsub('(%s*)%$([%w_]+)',function(sp,f)
      local subtmpl
      local s = tbl[f]
      if not s then error("not present in table "..f) end
      if getmetatable(s) == Template then
        subtmpl = s
        s = s.tmpl
      else
        s = tostring(s)
      end
      if s:find '\n' then
        local lines = usplit(s, '\n')
        for i, line in ipairs(lines) do
          lines[i] = sp..line
        end
        s = concat(lines, '\n') .. '\n'
      end
      if subtmpl then
        return _substitute(s, tbl)
      else
        return s
      end
    end)
  end

  local lines = {}
  for i, line in ipairs(self.strings) do
    lines[i] = subst(line)
  end
  return concat(lines,'\n')..'\n'
end



--- Miscelaneous
-- @section misc

--- return an iterator over all lines in a string
-- @string s the string
-- @return an iterator
-- @usage
-- local line_no = 1
-- for line in stringx.lines(some_text) do
--   print(line_no, line)
--   line_no = line_no + 1
-- end
function stringx.lines(s)
    assert_string(1,s)
    if not s:find '\n$' then s = s..'\n' end
    return s:gmatch('([^\n]*)\n')
end

--- inital word letters uppercase ('title case').
-- Here 'words' mean chunks of non-space characters.
-- @string s the string
-- @return a string with each word's first letter uppercase
-- @usage stringx.title("hello world") == "Hello World")
function stringx.title(s)
    assert_string(1,s)
    return (s:gsub('(%S)(%S*)',function(f,r)
        return f:upper()..r:lower()
    end))
end

stringx.capitalize = stringx.title

do
  local ellipsis = '...'
  local n_ellipsis = #ellipsis

  --- Return a shortened version of a string.
  -- Fits string within w characters. Removed characters are marked with ellipsis.
  -- @string s the string
  -- @int w the maxinum size allowed
  -- @bool tail true if we want to show the end of the string (head otherwise)
  -- @usage ('1234567890'):shorten(8) == '12345...'
  -- @usage ('1234567890'):shorten(8, true) == '...67890'
  -- @usage ('1234567890'):shorten(20) == '1234567890'
  function stringx.shorten(s,w,tail)
      assert_string(1,s)
      if #s > w then
          if w < n_ellipsis then return ellipsis:sub(1,w) end
          if tail then
              local i = #s - w + 1 + n_ellipsis
              return ellipsis .. s:sub(i)
          else
              return s:sub(1,w-n_ellipsis) .. ellipsis
          end
      end
      return s
  end
end


do
  -- Utility function that finds any patterns that match a long string's an open or close.
  -- Note that having this function use the least number of equal signs that is possible is a harder algorithm to come up with.
  -- Right now, it simply returns the greatest number of them found.
  -- @param s The string
  -- @return 'nil' if not found. If found, the maximum number of equal signs found within all matches.
  local function has_lquote(s)
      local lstring_pat = '([%[%]])(=*)%1'
      local equals, new_equals, _
      local finish = 1
      repeat
          _, finish, _, new_equals = s:find(lstring_pat, finish)
          if new_equals then
              equals = max(equals or 0, #new_equals)
          end
      until not new_equals

      return equals
  end

  --- Quote the given string and preserve any control or escape characters, such that reloading the string in Lua returns the same result.
  -- @param s The string to be quoted.
  -- @return The quoted string.
  function stringx.quote_string(s)
      assert_string(1,s)
      -- Find out if there are any embedded long-quote sequences that may cause issues.
      -- This is important when strings are embedded within strings, like when serializing.
      -- Append a closing bracket to catch unfinished long-quote sequences at the end of the string.
      local equal_signs = has_lquote(s .. "]")

      -- Note that strings containing "\r" can't be quoted using long brackets
      -- as Lua lexer converts all newlines to "\n" within long strings.
      if (s:find("\n") or equal_signs) and not s:find("\r") then
          -- If there is an embedded sequence that matches a long quote, then
          -- find the one with the maximum number of = signs and add one to that number.
          equal_signs = ("="):rep((equal_signs or -1) + 1)
          -- Long strings strip out leading newline. We want to retain that, when quoting.
          if s:find("^\n") then s = "\n" .. s end
          local lbracket, rbracket =
              "[" .. equal_signs .. "[",
              "]" .. equal_signs .. "]"
          s = lbracket .. s .. rbracket
      else
          -- Escape funny stuff. Lua 5.1 does not handle "\r" correctly.
          s = ("%q"):format(s):gsub("\r", "\\r")
      end
      return s
  end
end


--- Python-style formatting operator.
-- Calling `text.format_operator()` overloads the % operator for strings to give
-- Python/Ruby style formated output.
-- This is extended to also do template-like substitution for map-like data.
--
-- Note this goes further than the original, and will allow these cases:
--
-- 1. a single value
-- 2. a list of values
-- 3. a map of var=value pairs
-- 4. a function, as in gsub
--
-- For the second two cases, it uses $-variable substituion.
--
-- When called, this function will monkey-patch the global `string` metatable by
-- adding a `__mod` method.
--
-- See <a href="http://lua-users.org/wiki/StringInterpolation">the lua-users wiki</a>
--
-- @usage
-- require 'pl.text'.format_operator()
-- local out1 = '%s = %5.3f' % {'PI',math.pi}                   --> 'PI = 3.142'
-- local out2 = '$name = $value' % {name='dog',value='Pluto'}   --> 'dog = Pluto'
function stringx.format_operator()

  local format = string.format

  -- a more forgiving version of string.format, which applies
  -- tostring() to any value with a %s format.
  local function formatx (fmt,...)
    local args = pack(...)
    local i = 1
    for p in fmt:gmatch('%%.') do
      if p == '%s' and type(args[i]) ~= 'string' then
        args[i] = tostring(args[i])
      end
      i = i + 1
    end
    return format(fmt,unpack(args))
  end

  local function basic_subst(s,t)
    return (s:gsub('%$([%w_]+)',t))
  end

  getmetatable("").__mod = function(a, b)
    if b == nil then
      return a
    elseif type(b) == "table" and getmetatable(b) == nil then
      if #b == 0 then -- assume a map-like table
        return _substitute(a,b,true)
      else
        return formatx(a,unpack(b))
      end
    elseif type(b) == 'function' then
      return basic_subst(a,b)
    else
      return formatx(a,b)
    end
  end
end

--- import the stringx functions into the global string (meta)table
function stringx.import()
    utils.import(stringx,string)
end

return stringx

end,

["pl.tablex"] = function()
--------------------
-- Module: 'pl.tablex'
--------------------
--- Extended operations on Lua tables.
--
-- See @{02-arrays.md.Useful_Operations_on_Tables|the Guide}
--
-- Dependencies: `pl.utils`, `pl.types`
-- @module pl.tablex
local utils = require ('pl.utils')
local types = require ('pl.types')
local getmetatable,setmetatable,require = getmetatable,setmetatable,require
local tsort,append,remove = table.sort,table.insert,table.remove
local min = math.min
local pairs,type,unpack,select,tostring = pairs,type,utils.unpack,select,tostring
local function_arg = utils.function_arg
local assert_arg = utils.assert_arg

local tablex = {}

-- generally, functions that make copies of tables try to preserve the metatable.
-- However, when the source has no obvious type, then we attach appropriate metatables
-- like List, Map, etc to the result.
local function setmeta (res,tbl,pl_class)
    local mt = getmetatable(tbl) or pl_class and require('pl.' .. pl_class)
    return mt and setmetatable(res, mt) or res
end

local function makelist(l)
    return setmetatable(l, require('pl.List'))
end

local function makemap(m)
    return setmetatable(m, require('pl.Map'))
end

local function complain (idx,msg)
    error(('argument %d is not %s'):format(idx,msg),3)
end

local function assert_arg_indexable (idx,val)
    if not types.is_indexable(val) then
        complain(idx,"indexable")
    end
end

local function assert_arg_iterable (idx,val)
    if not types.is_iterable(val) then
        complain(idx,"iterable")
    end
end

local function assert_arg_writeable (idx,val)
    if not types.is_writeable(val) then
        complain(idx,"writeable")
    end
end

--- copy a table into another, in-place.
-- @within Copying
-- @tab t1 destination table
-- @tab t2 source (actually any iterable object)
-- @return first table
function tablex.update (t1,t2)
    assert_arg_writeable(1,t1)
    assert_arg_iterable(2,t2)
    for k,v in pairs(t2) do
        t1[k] = v
    end
    return t1
end

--- total number of elements in this table.
-- Note that this is distinct from `#t`, which is the number
-- of values in the array part; this value will always
-- be greater or equal. The difference gives the size of
-- the hash part, for practical purposes. Works for any
-- object with a __pairs metamethod.
-- @tab t a table
-- @return the size
function tablex.size (t)
    assert_arg_iterable(1,t)
    local i = 0
    for k in pairs(t) do i = i + 1 end
    return i
end

--- make a shallow copy of a table
-- @within Copying
-- @tab t an iterable source
-- @return new table
function tablex.copy (t)
    assert_arg_iterable(1,t)
    local res = {}
    for k,v in pairs(t) do
        res[k] = v
    end
    return res
end

local function cycle_aware_copy(t, cache)
    if type(t) ~= 'table' then return t end
    if cache[t] then return cache[t] end
    assert_arg_iterable(1,t)
    local res = {}
    cache[t] = res
    local mt = getmetatable(t)
    for k,v in pairs(t) do
        k = cycle_aware_copy(k, cache)
        v = cycle_aware_copy(v, cache)
        res[k] = v
    end
    setmetatable(res,mt)
    return res
end

--- make a deep copy of a table, recursively copying all the keys and fields.
-- This supports cycles in tables; cycles will be reproduced in the copy.
-- This will also set the copied table's metatable to that of the original.
-- @within Copying
-- @tab t A table
-- @return new table
function tablex.deepcopy(t)
    return cycle_aware_copy(t,{})
end

local abs = math.abs

local function cycle_aware_compare(t1,t2,ignore_mt,eps,cache)
    if cache[t1] and cache[t1][t2] then return true end
    local ty1 = type(t1)
    local ty2 = type(t2)
    if ty1 ~= ty2 then return false end
    -- non-table types can be directly compared
    if ty1 ~= 'table' then
        if ty1 == 'number' and eps then return abs(t1-t2) < eps end
        return t1 == t2
    end
    -- as well as tables which have the metamethod __eq
    local mt = getmetatable(t1)
    if not ignore_mt and mt and mt.__eq then return t1 == t2 end
    for k1 in pairs(t1) do
        if t2[k1]==nil then return false end
    end
    for k2 in pairs(t2) do
        if t1[k2]==nil then return false end
    end
    cache[t1] = cache[t1] or {}
    cache[t1][t2] = true
    for k1,v1 in pairs(t1) do
        local v2 = t2[k1]
        if not cycle_aware_compare(v1,v2,ignore_mt,eps,cache) then return false end
    end
    return true
end

--- compare two values.
-- if they are tables, then compare their keys and fields recursively.
-- @within Comparing
-- @param t1 A value
-- @param t2 A value
-- @bool[opt] ignore_mt if true, ignore __eq metamethod (default false)
-- @number[opt] eps if defined, then used for any number comparisons
-- @return true or false
function tablex.deepcompare(t1,t2,ignore_mt,eps)
    return cycle_aware_compare(t1,t2,ignore_mt,eps,{})
end

--- compare two arrays using a predicate.
-- @within Comparing
-- @array t1 an array
-- @array t2 an array
-- @func cmp A comparison function; `bool = cmp(t1_value, t2_value)`
-- @return true or false
-- @usage
-- assert(tablex.compare({ 1, 2, 3 }, { 1, 2, 3 }, "=="))
--
-- assert(tablex.compare(
--    {1,2,3, hello = "world"},  -- fields are not compared!
--    {1,2,3}, function(v1, v2) return v1 == v2 end)
function tablex.compare (t1,t2,cmp)
    assert_arg_indexable(1,t1)
    assert_arg_indexable(2,t2)
    if #t1 ~= #t2 then return false end
    cmp = function_arg(3,cmp)
    for k = 1,#t1 do
        if not cmp(t1[k],t2[k]) then return false end
    end
    return true
end

--- compare two list-like tables using an optional predicate, without regard for element order.
-- @within Comparing
-- @array t1 a list-like table
-- @array t2 a list-like table
-- @param cmp A comparison function (may be nil)
function tablex.compare_no_order (t1,t2,cmp)
    assert_arg_indexable(1,t1)
    assert_arg_indexable(2,t2)
    if cmp then cmp = function_arg(3,cmp) end
    if #t1 ~= #t2 then return false end
    local visited = {}
    for i = 1,#t1 do
        local val = t1[i]
        local gotcha
        for j = 1,#t2 do
            if not visited[j] then
                local match
                if cmp then match = cmp(val,t2[j]) else match = val == t2[j] end
                if match then
                    gotcha = j
                    break
                end
            end
        end
        if not gotcha then return false end
        visited[gotcha] = true
    end
    return true
end


--- return the index of a value in a list.
-- Like string.find, there is an optional index to start searching,
-- which can be negative.
-- @within Finding
-- @array t A list-like table
-- @param val A value
-- @int idx index to start; -1 means last element,etc (default 1)
-- @return index of value or nil if not found
-- @usage find({10,20,30},20) == 2
-- @usage find({'a','b','a','c'},'a',2) == 3
function tablex.find(t,val,idx)
    assert_arg_indexable(1,t)
    idx = idx or 1
    if idx < 0 then idx = #t + idx + 1 end
    for i = idx,#t do
        if t[i] == val then return i end
    end
    return nil
end

--- return the index of a value in a list, searching from the end.
-- Like string.find, there is an optional index to start searching,
-- which can be negative.
-- @within Finding
-- @array t A list-like table
-- @param val A value
-- @param idx index to start; -1 means last element,etc (default `#t`)
-- @return index of value or nil if not found
-- @usage rfind({10,10,10},10) == 3
function tablex.rfind(t,val,idx)
    assert_arg_indexable(1,t)
    idx = idx or #t
    if idx < 0 then idx = #t + idx + 1 end
    for i = idx,1,-1 do
        if t[i] == val then return i end
    end
    return nil
end


--- return the index (or key) of a value in a table using a comparison function.
--
-- *NOTE*: the 2nd return value of this function, the value returned
-- by the comparison function, has a limitation that it cannot be `false`.
-- Because if it is, then it indicates the comparison failed, and the
-- function will continue the search. See examples.
-- @within Finding
-- @tab t A table
-- @func cmp A comparison function
-- @param arg an optional second argument to the function
-- @return index of value, or nil if not found
-- @return value returned by comparison function (cannot be `false`!)
-- @usage
-- -- using an operator
-- local lst = { "Rudolph", true, false, 15 }
-- local idx, cmp_result = tablex.rfind(lst, "==", "Rudolph")
-- assert(idx == 1)
-- assert(cmp_result == true)
--
-- local idx, cmp_result = tablex.rfind(lst, "==", false)
-- assert(idx == 3)
-- assert(cmp_result == true)       -- looking up 'false' works!
--
-- -- using a function returning the value looked up
-- local cmp = function(v1, v2) return v1 == v2 and v2 end
-- local idx, cmp_result = tablex.rfind(lst, cmp, "Rudolph")
-- assert(idx == 1)
-- assert(cmp_result == "Rudolph")  -- the value is returned
--
-- -- NOTE: this fails, since 'false' cannot be returned!
-- local idx, cmp_result = tablex.rfind(lst, cmp, false)
-- assert(idx == nil)               -- looking up 'false' failed!
-- assert(cmp_result == nil)
function tablex.find_if(t,cmp,arg)
    assert_arg_iterable(1,t)
    cmp = function_arg(2,cmp)
    for k,v in pairs(t) do
        local c = cmp(v,arg)
        if c then return k,c end
    end
    return nil
end

--- return a list of all values in a table indexed by another list.
-- @tab tbl a table
-- @array idx an index table (a list of keys)
-- @return a list-like table
-- @usage index_by({10,20,30,40},{2,4}) == {20,40}
-- @usage index_by({one=1,two=2,three=3},{'one','three'}) == {1,3}
function tablex.index_by(tbl,idx)
    assert_arg_indexable(1,tbl)
    assert_arg_indexable(2,idx)
    local res = {}
    for i = 1,#idx do
        res[i] = tbl[idx[i]]
    end
    return setmeta(res,tbl,'List')
end

--- apply a function to all values of a table.
-- This returns a table of the results.
-- Any extra arguments are passed to the function.
-- @within MappingAndFiltering
-- @func fun A function that takes at least one argument
-- @tab t A table
-- @param ... optional arguments
-- @usage map(function(v) return v*v end, {10,20,30,fred=2}) is {100,400,900,fred=4}
function tablex.map(fun,t,...)
    assert_arg_iterable(1,t)
    fun = function_arg(1,fun)
    local res = {}
    for k,v in pairs(t) do
        res[k] = fun(v,...)
    end
    return setmeta(res,t)
end

--- apply a function to all values of a list.
-- This returns a table of the results.
-- Any extra arguments are passed to the function.
-- @within MappingAndFiltering
-- @func fun A function that takes at least one argument
-- @array t a table (applies to array part)
-- @param ... optional arguments
-- @return a list-like table
-- @usage imap(function(v) return v*v end, {10,20,30,fred=2}) is {100,400,900}
function tablex.imap(fun,t,...)
    assert_arg_indexable(1,t)
    fun = function_arg(1,fun)
    local res = {}
    for i = 1,#t do
        res[i] = fun(t[i],...) or false
    end
    return setmeta(res,t,'List')
end

--- apply a named method to values from a table.
-- @within MappingAndFiltering
-- @string name the method name
-- @array t a list-like table
-- @param ... any extra arguments to the method
-- @return a `List` with the results of the method (1st result only)
-- @usage
-- local Car = {}
-- Car.__index = Car
-- function Car.new(car)
--   return setmetatable(car or {}, Car)
-- end
-- Car.speed = 0
-- function Car:faster(increase)
--   self.speed = self.speed + increase
--   return self.speed
-- end
--
-- local ferrari = Car.new{ name = "Ferrari" }
-- local lamborghini = Car.new{ name = "Lamborghini", speed = 50 }
-- local cars = { ferrari, lamborghini }
--
-- assert(ferrari.speed == 0)
-- assert(lamborghini.speed == 50)
-- tablex.map_named_method("faster", cars, 10)
-- assert(ferrari.speed == 10)
-- assert(lamborghini.speed == 60)
function tablex.map_named_method (name,t,...)
    utils.assert_string(1,name)
    assert_arg_indexable(2,t)
    local res = {}
    for i = 1,#t do
        local val = t[i]
        local fun = val[name]
        res[i] = fun(val,...)
    end
    return setmeta(res,t,'List')
end

--- apply a function to all values of a table, in-place.
-- Any extra arguments are passed to the function.
-- @func fun A function that takes at least one argument
-- @tab t a table
-- @param ... extra arguments passed to `fun`
-- @see tablex.foreach
function tablex.transform (fun,t,...)
    assert_arg_iterable(1,t)
    fun = function_arg(1,fun)
    for k,v in pairs(t) do
        t[k] = fun(v,...)
    end
end

--- generate a table of all numbers in a range.
-- This is consistent with a numerical for loop.
-- @int start  number
-- @int finish number
-- @int[opt=1] step  make this negative for start < finish
function tablex.range (start,finish,step)
    local res
    step = step or 1
    if start == finish then
        res = {start}
    elseif (start > finish and step > 0) or (finish > start and step < 0) then
        res = {}
    else
        local k = 1
        res = {}
        for i=start,finish,step do res[k]=i; k=k+1 end
    end
    return makelist(res)
end

--- apply a function to values from two tables.
-- @within MappingAndFiltering
-- @func fun a function of at least two arguments
-- @tab t1 a table
-- @tab t2 a table
-- @param ... extra arguments
-- @return a table
-- @usage map2('+',{1,2,3,m=4},{10,20,30,m=40}) is {11,22,23,m=44}
function tablex.map2 (fun,t1,t2,...)
    assert_arg_iterable(1,t1)
    assert_arg_iterable(2,t2)
    fun = function_arg(1,fun)
    local res = {}
    for k,v in pairs(t1) do
        res[k] = fun(v,t2[k],...)
    end
    return setmeta(res,t1,'List')
end

--- apply a function to values from two arrays.
-- The result will be the length of the shortest array.
-- @within MappingAndFiltering
-- @func fun a function of at least two arguments
-- @array t1 a list-like table
-- @array t2 a list-like table
-- @param ... extra arguments
-- @usage imap2('+',{1,2,3,m=4},{10,20,30,m=40}) is {11,22,23}
function tablex.imap2 (fun,t1,t2,...)
    assert_arg_indexable(2,t1)
    assert_arg_indexable(3,t2)
    fun = function_arg(1,fun)
    local res,n = {},math.min(#t1,#t2)
    for i = 1,n do
        res[i] = fun(t1[i],t2[i],...)
    end
    return res
end

--- 'reduce' a list using a binary function.
-- @func fun a function of two arguments
-- @array t a list-like table
-- @array memo optional initial memo value. Defaults to first value in table.
-- @return the result of the function
-- @usage reduce('+',{1,2,3,4}) == 10
function tablex.reduce (fun,t,memo)
    assert_arg_indexable(2,t)
    fun = function_arg(1,fun)
    local n = #t
    if n == 0 then
        return memo
    end
    local res = memo and fun(memo, t[1]) or t[1]
    for i = 2,n do
        res = fun(res,t[i])
    end
    return res
end

--- apply a function to all elements of a table.
-- The arguments to the function will be the value,
-- the key and _finally_ any extra arguments passed to this function.
-- Note that the Lua 5.0 function table.foreach passed the _key_ first.
-- @within Iterating
-- @tab t a table
-- @func fun a function on the elements; `function(value, key, ...)`
-- @param ... extra arguments passed to `fun`
-- @see tablex.transform
function tablex.foreach(t,fun,...)
    assert_arg_iterable(1,t)
    fun = function_arg(2,fun)
    for k,v in pairs(t) do
        fun(v,k,...)
    end
end

--- apply a function to all elements of a list-like table in order.
-- The arguments to the function will be the value,
-- the index and _finally_ any extra arguments passed to this function
-- @within Iterating
-- @array t a table
-- @func fun a function with at least one argument
-- @param ... optional arguments
function tablex.foreachi(t,fun,...)
    assert_arg_indexable(1,t)
    fun = function_arg(2,fun)
    for i = 1,#t do
        fun(t[i],i,...)
    end
end

--- Apply a function to a number of tables.
-- A more general version of map
-- The result is a table containing the result of applying that function to the
-- ith value of each table. Length of output list is the minimum length of all the lists
-- @within MappingAndFiltering
-- @func fun a function of n arguments
-- @tab ... n tables
-- @usage mapn(function(x,y,z) return x+y+z end, {1,2,3},{10,20,30},{100,200,300}) is {111,222,333}
-- @usage mapn(math.max, {1,20,300},{10,2,3},{100,200,100}) is    {100,200,300}
-- @param fun A function that takes as many arguments as there are tables
function tablex.mapn(fun,...)
    fun = function_arg(1,fun)
    local res = {}
    local lists = {...}
    local minn = 1e40
    for i = 1,#lists do
        minn = min(minn,#(lists[i]))
    end
    for i = 1,minn do
        local args,k = {},1
        for j = 1,#lists do
            args[k] = lists[j][i]
            k = k + 1
        end
        res[#res+1] = fun(unpack(args))
    end
    return res
end

--- call the function with the key and value pairs from a table.
-- The function can return a value and a key (note the order!). If both
-- are not nil, then this pair is inserted into the result: if the key already exists, we convert the value for that
-- key into a table and append into it. If only value is not nil, then it is appended to the result.
-- @within MappingAndFiltering
-- @func fun A function which will be passed each key and value as arguments, plus any extra arguments to pairmap.
-- @tab t A table
-- @param ... optional arguments
-- @usage pairmap(function(k,v) return v end,{fred=10,bonzo=20}) is {10,20} _or_ {20,10}
-- @usage pairmap(function(k,v) return {k,v},k end,{one=1,two=2}) is {one={'one',1},two={'two',2}}
function tablex.pairmap(fun,t,...)
    assert_arg_iterable(1,t)
    fun = function_arg(1,fun)
    local res = {}
    for k,v in pairs(t) do
        local rv,rk = fun(k,v,...)
        if rk then
            if res[rk] then
                if type(res[rk]) == 'table' then
                    table.insert(res[rk],rv)
                else
                    res[rk] = {res[rk], rv}
                end
            else
                res[rk] = rv
            end
        else
            res[#res+1] = rv
        end
    end
    return res
end

local function keys_op(i,v) return i end

--- return all the keys of a table in arbitrary order.
-- @within Extraction
--  @tab t A table
function tablex.keys(t)
    assert_arg_iterable(1,t)
    return makelist(tablex.pairmap(keys_op,t))
end

local function values_op(i,v) return v end

--- return all the values of the table in arbitrary order
-- @within Extraction
--  @tab t A table
function tablex.values(t)
    assert_arg_iterable(1,t)
    return makelist(tablex.pairmap(values_op,t))
end

local function index_map_op (i,v) return i,v end

--- create an index map from a list-like table. The original values become keys,
-- and the associated values are the indices into the original list.
-- @array t a list-like table
-- @return a map-like table
function tablex.index_map (t)
    assert_arg_indexable(1,t)
    return makemap(tablex.pairmap(index_map_op,t))
end

local function set_op(i,v) return true,v end

--- create a set from a list-like table. A set is a table where the original values
-- become keys, and the associated values are all true.
-- @array t a list-like table
-- @return a set (a map-like table)
function tablex.makeset (t)
    assert_arg_indexable(1,t)
    return setmetatable(tablex.pairmap(set_op,t),require('pl.Set'))
end

--- combine two tables, either as union or intersection. Corresponds to
-- set operations for sets () but more general. Not particularly
-- useful for list-like tables.
-- @within Merging
-- @tab t1 a table
-- @tab t2 a table
-- @bool dup true for a union, false for an intersection.
-- @usage merge({alice=23,fred=34},{bob=25,fred=34}) is {fred=34}
-- @usage merge({alice=23,fred=34},{bob=25,fred=34},true) is {bob=25,fred=34,alice=23}
-- @see tablex.index_map
function tablex.merge (t1,t2,dup)
    assert_arg_iterable(1,t1)
    assert_arg_iterable(2,t2)
    local res = {}
    for k,v in pairs(t1) do
        if dup or t2[k] then res[k] = v end
    end
    if dup then
      for k,v in pairs(t2) do
        res[k] = v
      end
    end
    return setmeta(res,t1,'Map')
end

--- the union of two map-like tables.
-- If there are duplicate keys, the second table wins.
-- @tab t1 a table
-- @tab t2 a table
-- @treturn tab
-- @see tablex.merge
function tablex.union(t1, t2)
    return tablex.merge(t1, t2, true)
end

--- the intersection of two map-like tables.
-- @tab t1 a table
-- @tab t2 a table
-- @treturn tab
-- @see tablex.merge
function tablex.intersection(t1, t2)
    return tablex.merge(t1, t2, false)
end

--- a new table which is the difference of two tables.
-- With sets (where the values are all true) this is set difference and
-- symmetric difference depending on the third parameter.
-- @within Merging
-- @tab s1 a map-like table or set
-- @tab s2 a map-like table or set
-- @bool symm symmetric difference (default false)
-- @return a map-like table or set
function tablex.difference (s1,s2,symm)
    assert_arg_iterable(1,s1)
    assert_arg_iterable(2,s2)
    local res = {}
    for k,v in pairs(s1) do
        if s2[k] == nil then res[k] = v end
    end
    if symm then
        for k,v in pairs(s2) do
            if s1[k] == nil then res[k] = v end
        end
    end
    return setmeta(res,s1,'Map')
end

--- A table where the key/values are the values and value counts of the table.
-- @array t a list-like table
-- @func cmp a function that defines equality (otherwise uses ==)
-- @return a map-like table
-- @see seq.count_map
function tablex.count_map (t,cmp)
    assert_arg_indexable(1,t)
    local res,mask = {},{}
    cmp = function_arg(2,cmp or '==')
    local n = #t
    for i = 1,#t do
        local v = t[i]
        if not mask[v] then
            mask[v] = true
            -- check this value against all other values
            res[v] = 1  -- there's at least one instance
            for j = i+1,n do
                local w = t[j]
                local ok = cmp(v,w)
                if ok then
                    res[v] = res[v] + 1
                    mask[w] = true
                end
            end
        end
    end
    return makemap(res)
end

--- filter an array's values using a predicate function
-- @within MappingAndFiltering
-- @array t a list-like table
-- @func pred a boolean function
-- @param arg optional argument to be passed as second argument of the predicate
function tablex.filter (t,pred,arg)
    assert_arg_indexable(1,t)
    pred = function_arg(2,pred)
    local res,k = {},1
    for i = 1,#t do
        local v = t[i]
        if pred(v,arg) then
            res[k] = v
            k = k + 1
        end
    end
    return setmeta(res,t,'List')
end

--- return a table where each element is a table of the ith values of an arbitrary
-- number of tables. It is equivalent to a matrix transpose.
-- @within Merging
-- @usage zip({10,20,30},{100,200,300}) is {{10,100},{20,200},{30,300}}
-- @array ... arrays to be zipped
function tablex.zip(...)
    return tablex.mapn(function(...) return {...} end,...)
end

local _copy
function _copy (dest,src,idest,isrc,nsrc,clean_tail)
    idest = idest or 1
    isrc = isrc or 1
    local iend
    if not nsrc then
        nsrc = #src
        iend = #src
    else
        iend = isrc + min(nsrc-1,#src-isrc)
    end
    if dest == src then -- special case
        if idest > isrc and iend >= idest then -- overlapping ranges
            src = tablex.sub(src,isrc,nsrc)
            isrc = 1; iend = #src
        end
    end
    for i = isrc,iend do
        dest[idest] = src[i]
        idest = idest + 1
    end
    if clean_tail then
        tablex.clear(dest,idest)
    end
    return dest
end

--- copy an array into another one, clearing `dest` after `idest+nsrc`, if necessary.
-- @within Copying
-- @array dest a list-like table
-- @array src a list-like table
-- @int[opt=1] idest where to start copying values into destination
-- @int[opt=1] isrc where to start copying values from source
-- @int[opt=#src] nsrc number of elements to copy from source
function tablex.icopy (dest,src,idest,isrc,nsrc)
    assert_arg_indexable(1,dest)
    assert_arg_indexable(2,src)
    return _copy(dest,src,idest,isrc,nsrc,true)
end

--- copy an array into another one.
-- @within Copying
-- @array dest a list-like table
-- @array src a list-like table
-- @int[opt=1] idest where to start copying values into destination
-- @int[opt=1] isrc where to start copying values from source
-- @int[opt=#src] nsrc number of elements to copy from source
function tablex.move (dest,src,idest,isrc,nsrc)
    assert_arg_indexable(1,dest)
    assert_arg_indexable(2,src)
    return _copy(dest,src,idest,isrc,nsrc,false)
end

function tablex._normalize_slice(self,first,last)
  local sz = #self
  if not first then first=1 end
  if first<0 then first=sz+first+1 end
  -- make the range _inclusive_!
  if not last then last=sz end
  if last < 0 then last=sz+1+last end
  return first,last
end

--- Extract a range from a table, like  'string.sub'.
-- If first or last are negative then they are relative to the end of the list
-- eg. sub(t,-2) gives last 2 entries in a list, and
-- sub(t,-4,-2) gives from -4th to -2nd
-- @within Extraction
-- @array t a list-like table
-- @int first An index
-- @int last An index
-- @return a new List
function tablex.sub(t,first,last)
    assert_arg_indexable(1,t)
    first,last = tablex._normalize_slice(t,first,last)
    local res={}
    for i=first,last do append(res,t[i]) end
    return setmeta(res,t,'List')
end

--- set an array range to a value. If it's a function we use the result
-- of applying it to the indices.
-- @array t a list-like table
-- @param val a value
-- @int[opt=1] i1 start range
-- @int[opt=#t] i2 end range
function tablex.set (t,val,i1,i2)
    assert_arg_indexable(1,t)
    i1,i2 = i1 or 1,i2 or #t
    if types.is_callable(val) then
        for i = i1,i2 do
            t[i] = val(i)
        end
    else
        for i = i1,i2 do
            t[i] = val
        end
    end
end

--- create a new array of specified size with initial value.
-- @int n size
-- @param val initial value (can be `nil`, but don't expect `#` to work!)
-- @return the table
function tablex.new (n,val)
    local res = {}
    tablex.set(res,val,1,n)
    return res
end

--- clear out the contents of a table.
-- @array t a list
-- @param istart optional start position
function tablex.clear(t,istart)
    istart = istart or 1
    for i = istart,#t do remove(t) end
end

--- insert values into a table.
-- similar to `table.insert` but inserts values from given table `values`,
-- not the object itself, into table `t` at position `pos`.
-- @within Copying
-- @array t the list
-- @int[opt] position (default is at end)
-- @array values
function tablex.insertvalues(t, ...)
    assert_arg(1,t,'table')
    local pos, values
    if select('#', ...) == 1 then
        pos,values = #t+1, ...
    else
        pos,values = ...
    end
    if #values > 0 then
        for i=#t,pos,-1 do
            t[i+#values] = t[i]
        end
        local offset = 1 - pos
        for i=pos,pos+#values-1 do
            t[i] = values[i + offset]
        end
    end
    return t
end

--- remove a range of values from a table.
-- End of range may be negative.
-- @array t a list-like table
-- @int i1 start index
-- @int i2 end index
-- @return the table
function tablex.removevalues (t,i1,i2)
    assert_arg(1,t,'table')
    i1,i2 = tablex._normalize_slice(t,i1,i2)
    for i = i1,i2 do
        remove(t,i1)
    end
    return t
end

local _find
_find = function (t,value,tables)
    for k,v in pairs(t) do
        if v == value then return k end
    end
    for k,v in pairs(t) do
        if not tables[v] and type(v) == 'table' then
            tables[v] = true
            local res = _find(v,value,tables)
            if res then
                res = tostring(res)
                if type(k) ~= 'string' then
                    return '['..k..']'..res
                else
                    return k..'.'..res
                end
            end
        end
    end
end

--- find a value in a table by recursive search.
-- @within Finding
-- @tab t the table
-- @param value the value
-- @array[opt] exclude any tables to avoid searching
-- @return a fieldspec, e.g. 'a.b' or 'math.sin'
-- @usage search(_G,math.sin,{package.path}) == 'math.sin'
function tablex.search (t,value,exclude)
    assert_arg_iterable(1,t)
    local tables = {[t]=true}
    if exclude then
        for _,v in pairs(exclude) do tables[v] = true end
    end
    return _find(t,value,tables)
end

--- return an iterator to a table sorted by its keys
-- @within Iterating
-- @tab t the table
-- @func f an optional comparison function (f(x,y) is true if x < y)
-- @usage for k,v in tablex.sort(t) do print(k,v) end
-- @return an iterator to traverse elements sorted by the keys
function tablex.sort(t,f)
    local keys = {}
    for k in pairs(t) do keys[#keys + 1] = k end
    tsort(keys,f)
    local i = 0
    return function()
        i = i + 1
        return keys[i], t[keys[i]]
    end
end

--- return an iterator to a table sorted by its values
-- @within Iterating
-- @tab t the table
-- @func f an optional comparison function (f(x,y) is true if x < y)
-- @usage for k,v in tablex.sortv(t) do print(k,v) end
-- @return an iterator to traverse elements sorted by the values
function tablex.sortv(t,f)
    f = function_arg(2, f or '<')
    local keys = {}
    for k in pairs(t) do keys[#keys + 1] = k end
    tsort(keys,function(x, y) return f(t[x], t[y]) end)
    local i = 0
    return function()
        i = i + 1
        return keys[i], t[keys[i]]
    end
end

--- modifies a table to be read only.
-- This only offers weak protection. Tables can still be modified with
-- `table.insert` and `rawset`.
--
-- *NOTE*: for Lua 5.1 length, pairs and ipairs will not work, since the
-- equivalent metamethods are only available in Lua 5.2 and newer.
-- @tab t the table
-- @return the table read only (a proxy).
function tablex.readonly(t)
    local mt = {
        __index=t,
        __newindex=function(t, k, v) error("Attempt to modify read-only table", 2) end,
        __pairs=function() return pairs(t) end,
        __ipairs=function() return ipairs(t) end,
        __len=function() return #t end,
        __metatable=false
    }
    return setmetatable({}, mt)
end

return tablex

end,

["pl.template"] = function()
--------------------
-- Module: 'pl.template'
--------------------
--- A template preprocessor.
-- Originally by [Ricki Lake](http://lua-users.org/wiki/SlightlyLessSimpleLuaPreprocessor)
--
-- There are two rules:
--
--  * lines starting with # are Lua
--  * otherwise, `$(expr)` is the result of evaluating `expr`
--
-- Example:
--
--    #  for i = 1,3 do
--       $(i) Hello, Word!
--    #  end
--    ===>
--    1 Hello, Word!
--    2 Hello, Word!
--    3 Hello, Word!
--
-- Other escape characters can be used, when the defaults conflict
-- with the output language.
--
--    > for _,n in pairs{'one','two','three'} do
--    static int l_${n} (luaState *state);
--    > end
--
-- See  @{03-strings.md.Another_Style_of_Template|the Guide}.
--
-- Dependencies: `pl.utils`
-- @module pl.template

local utils = require 'pl.utils'

local append,format,strsub,strfind,strgsub = table.insert,string.format,string.sub,string.find,string.gsub

local APPENDER = "\n__R_size = __R_size + 1; __R_table[__R_size] = "

local function parseDollarParen(pieces, chunk, exec_pat, newline)
    local s = 1
    for term, executed, e in chunk:gmatch(exec_pat) do
        executed = '('..strsub(executed,2,-2)..')'
        append(pieces, APPENDER..format("%q", strsub(chunk,s, term - 1)))
        append(pieces, APPENDER..format("__tostring(%s or '')", executed))
        s = e
    end
    local r
    if newline then
        r = format("%q", strgsub(strsub(chunk,s),"\n",""))
    else
        r = format("%q", strsub(chunk,s))
    end
    if r ~= '""' then
        append(pieces, APPENDER..r)
    end
end

local function parseHashLines(chunk,inline_escape,brackets,esc,newline)
    local exec_pat = "()"..inline_escape.."(%b"..brackets..")()"

    local esc_pat = esc.."+([^\n]*\n?)"
    local esc_pat1, esc_pat2 = "^"..esc_pat, "\n"..esc_pat
    local  pieces, s = {"return function()\nlocal __R_size, __R_table, __tostring = 0, {}, __tostring", n = 1}, 1
    while true do
        local _, e, lua = strfind(chunk,esc_pat1, s)
        if not e then
            local ss
            ss, e, lua = strfind(chunk,esc_pat2, s)
            parseDollarParen(pieces, strsub(chunk,s, ss), exec_pat, newline)
            if not e then break end
        end
        if strsub(lua, -1, -1) == "\n" then lua = strsub(lua, 1, -2) end
        append(pieces, "\n"..lua)
        s = e + 1
    end
    append(pieces, "\nreturn __R_table\nend")

    -- let's check for a special case where there is nothing to template, but it's
    -- just a single static string
    local short = false
    if (#pieces == 3) and (pieces[2]:find(APPENDER, 1, true) == 1) then
        pieces = { "return " .. pieces[2]:sub(#APPENDER+1,-1) }
        short = true
    end
    -- if short == true, the generated function will not return a table of strings,
    -- but a single string
    return table.concat(pieces), short
end

local template = {}

--- expand the template using the specified environment.
-- This function will compile and render the template. For more performant
-- recurring usage use the two step approach by using `compile` and `ct:render`.
-- There are six special fields in the environment table `env`
--
--   * `_parent`: continue looking up in this table (e.g. `_parent=_G`).
--   * `_brackets`: bracket pair that wraps inline Lua expressions,  default is '()'.
--   * `_escape`: character marking Lua lines, default is '#'
--   * `_inline_escape`: character marking inline Lua expression, default is '$'.
--   * `_chunk_name`: chunk name for loaded templates, used if there
--     is an error in Lua code. Default is 'TMP'.
--   * `_debug`: if truthy, the generated code will be printed upon a render error
--
-- @string str the template string
-- @tab[opt] env the environment
-- @return `rendered template + nil + source_code`, or `nil + error + source_code`. The last
-- return value (`source_code`) is only returned if the debug option is used.
function template.substitute(str,env)
    env = env or {}
    local t, err = template.compile(str, {
        chunk_name = rawget(env,"_chunk_name"),
        escape = rawget(env,"_escape"),
        inline_escape = rawget(env,"_inline_escape"),
        inline_brackets = rawget(env,"_brackets"),
        newline = nil,
        debug = rawget(env,"_debug")
    })
    if not t then return t, err end

    return t:render(env, rawget(env,"_parent"), rawget(env,"_debug"))
end

--- executes the previously compiled template and renders it.
-- @function ct:render
-- @tab[opt] env the environment.
-- @tab[opt] parent continue looking up in this table (e.g. `parent=_G`).
-- @bool[opt] db if thruthy, it will print the code upon a render error
-- (provided the template was compiled with the debug option).
-- @return `rendered template + nil + source_code`, or `nil + error + source_code`. The last return value
-- (`source_code`) is only returned if the template was compiled with the debug option.
-- @usage
-- local ct, err = template.compile(my_template)
-- local rendered , err = ct:render(my_env, parent)
local render = function(self, env, parent, db)
    env = env or {}
    if parent then  -- parent is a bit silly, but for backward compatibility retained
        setmetatable(env, {__index = parent})
    end
    setmetatable(self.env, {__index = env})

    local res, out = xpcall(self.fn, debug.traceback)
    if not res then
        if self.code and db then print(self.code) end
        return nil, out, self.code
    end
    return table.concat(out), nil, self.code
end

--- compiles the template.
-- Returns an object that can repeatedly be rendered without parsing/compiling
-- the template again.
-- The options passed in the `opts` table support the following options:
--
--   * `chunk_name`: chunk name for loaded templates, used if there
--     is an error in Lua code. Default is 'TMP'.
--   * `escape`: character marking Lua lines, default is '#'
--   * `inline_escape`: character marking inline Lua expression, default is '$'.
--   * `inline_brackets`: bracket pair that wraps inline Lua expressions, default is '()'.
--   * `newline`: string to replace newline characters, default is `nil` (not replacing newlines).
--   * `debug`: if truthy, the generated source code will be retained within the compiled template object, default is `nil`.
--
-- @string str the template string
-- @tab[opt] opts the compilation options to use
-- @return template object, or `nil + error + source_code`
-- @usage
-- local ct, err = template.compile(my_template)
-- local rendered , err = ct:render(my_env, parent)
function template.compile(str, opts)
    opts = opts or {}
    local chunk_name = opts.chunk_name or 'TMP'
    local escape = opts.escape or '#'
    local inline_escape = opts.inline_escape or '$'
    local inline_brackets = opts.inline_brackets or '()'

    local code, short = parseHashLines(str,inline_escape,inline_brackets,escape,opts.newline)
    local env = { __tostring = tostring }
    local fn, err = utils.load(code, chunk_name,'t',env)
    if not fn then return nil, err, code end

    if short then
        -- the template returns a single constant string, let's optimize for that
        local constant_string = fn()
        return {
            fn = fn(),
            env = env,
            render = function(self) -- additional params can be ignored
                -- skip the metatable magic and error handling in the render
                -- function above for this special case
                return constant_string, nil, self.code
            end,
            code = opts.debug and code or nil,
        }
    end

    return {
        fn = fn(),
        env = env,
        render = render,
        code = opts.debug and code or nil,
    }
end

return template

end,

["pl.test"] = function()
--------------------
-- Module: 'pl.test'
--------------------
--- Useful test utilities.
--
--    test.asserteq({1,2},{1,2}) -- can compare tables
--    test.asserteq(1.2,1.19,0.02) -- compare FP numbers within precision
--    T = test.tuple -- used for comparing multiple results
--    test.asserteq(T(string.find(" me","me")),T(2,3))
--
-- Dependencies: `pl.utils`, `pl.tablex`, `pl.pretty`, `pl.path`, `debug`
-- @module pl.test

local tablex = require 'pl.tablex'
local utils = require 'pl.utils'
local pretty = require 'pl.pretty'
local path = require 'pl.path'
local type,unpack,pack = type,utils.unpack,utils.pack
local clock = os.clock
local debug = require 'debug'
local io = io

local function dump(x)
    if type(x) == 'table' and not (getmetatable(x) and getmetatable(x).__tostring) then
        return pretty.write(x,' ',true)
    elseif type(x) == 'string' then
        return '"'..x..'"'
    else
        return tostring(x)
    end
end

local test = {}

---- error handling for test results.
-- By default, this writes to stderr and exits the program.
-- Re-define this function to raise an error and/or redirect output
function test.error_handler(file,line,got_text, needed_text,msg)
    local err = io.stderr
    err:write(path.basename(file)..':'..line..': assertion failed\n')
    err:write("got:\t",got_text,'\n')
    err:write("needed:\t",needed_text,'\n')
    utils.quit(1,msg or "these values were not equal")
end

local function complain (x,y,msg,where)
    local i = debug.getinfo(3 + (where or 0))
    test.error_handler(i.short_src,i.currentline,dump(x),dump(y),msg)
end

--- general test complain message.
-- Useful for composing new test functions (see tests/tablex.lua for an example)
-- @param x a value
-- @param y value to compare first value against
-- @param msg message
-- @param where extra level offset for errors
-- @function complain
test.complain = complain

--- like assert, except takes two arguments that must be equal and can be tables.
-- If they are plain tables, it will use tablex.deepcompare.
-- @param x any value
-- @param y a value equal to x
-- @param eps an optional tolerance for numerical comparisons
-- @param where extra level offset
function test.asserteq (x,y,eps,where)
    local res = x == y
    if not res then
        res = tablex.deepcompare(x,y,true,eps)
    end
    if not res then
        complain(x,y,nil,where)
    end
end

--- assert that the first string matches the second.
-- @param s1 a string
-- @param s2 a string
-- @param where extra level offset
function test.assertmatch (s1,s2,where)
    if not s1:match(s2) then
        complain (s1,s2,"these strings did not match",where)
    end
end

--- assert that the function raises a particular error.
-- @param fn a function or a table of the form {function,arg1,...}
-- @param e a string to match the error against
-- @param where extra level offset
function test.assertraise(fn,e,where)
    local ok, err
    if type(fn) == 'table' then
        ok, err = pcall(unpack(fn))
    else
        ok, err = pcall(fn)
    end
    if ok or err:match(e)==nil then
        complain (err,e,"these errors did not match",where)
    end
end

--- a version of asserteq that takes two pairs of values.
-- <code>x1==y1 and x2==y2</code> must be true. Useful for functions that naturally
-- return two values.
-- @param x1 any value
-- @param x2 any value
-- @param y1 any value
-- @param y2 any value
-- @param where extra level offset
function test.asserteq2 (x1,x2,y1,y2,where)
    if x1 ~= y1 then complain(x1,y1,nil,where) end
    if x2 ~= y2 then complain(x2,y2,nil,where) end
end

-- tuple type --

local tuple_mt = {
    unpack = unpack
}
tuple_mt.__index = tuple_mt

function tuple_mt.__tostring(self)
    local ts = {}
    for i=1, self.n do
        local s = self[i]
        ts[i] = type(s) == 'string' and ('%q'):format(s) or tostring(s)
    end
    return 'tuple(' .. table.concat(ts, ', ') .. ')'
end

function tuple_mt.__eq(a, b)
    if a.n ~= b.n then return false end
    for i=1, a.n do
        if a[i] ~= b[i] then return false end
    end
    return true
end

function tuple_mt.__len(self)
    return self.n
end

--- encode an arbitrary argument list as a tuple.
-- This can be used to compare to other argument lists, which is
-- very useful for testing functions which return a number of values.
-- Unlike regular array-like tables ('sequences') they may contain nils.
-- Tuples understand equality and know how to print themselves out.
-- The # operator is defined to be the size, irrespecive of any nils,
-- and there is an `unpack` method.
-- @usage asserteq(tuple( ('ab'):find 'a'), tuple(1,1))
function test.tuple(...)
    return setmetatable(pack(...), tuple_mt)
end

--- Time a function. Call the function a given number of times, and report the number of seconds taken,
-- together with a message.  Any extra arguments will be passed to the function.
-- @string msg a descriptive message
-- @int n number of times to call the function
-- @func fun the function
-- @param ... optional arguments to fun
function test.timer(msg,n,fun,...)
    local start = clock()
    for i = 1,n do fun(...) end
    utils.printf("%s: took %7.2f sec\n",msg,clock()-start)
end

return test

end,

["pl.text"] = function()
--------------------
-- Module: 'pl.text'
--------------------
--- Text processing utilities.
--
-- This provides a Template class (modeled after the same from the Python
-- libraries, see string.Template). It also provides similar functions to those
-- found in the textwrap module.
--
-- IMPORTANT: this module has been deprecated and will be removed in a future
-- version (2.0). The contents of this module have moved to the `pl.stringx`
-- module.
--
-- See  @{03-strings.md.String_Templates|the Guide}.
--
-- Dependencies: `pl.stringx`, `pl.utils`
-- @module pl.text

local utils = require("pl.utils")

utils.raise_deprecation {
  source = "Penlight " .. utils._VERSION,
  message = "the contents of module 'pl.text' has moved into 'pl.stringx'",
  version_removed = "2.0.0",
  deprecated_after = "1.11.0",
  no_trace = true,
}

return require "pl.stringx"

end,

["pl.types"] = function()
--------------------
-- Module: 'pl.types'
--------------------
---- Dealing with Detailed Type Information

-- Dependencies `pl.utils`
-- @module pl.types

local utils = require 'pl.utils'
local math_ceil = math.ceil
local assert_arg = utils.assert_arg
local types = {}

--- is the object either a function or a callable object?.
-- @param obj Object to check.
function types.is_callable (obj)
    return type(obj) == 'function' or getmetatable(obj) and getmetatable(obj).__call and true
end

--- is the object of the specified type?.
-- If the type is a string, then use type, otherwise compare with metatable.
--
-- NOTE: this function is imported from `utils.is_type`.
-- @param obj An object to check
-- @param tp The expected type
-- @function is_type
-- @see utils.is_type
types.is_type = utils.is_type

local fileMT = getmetatable(io.stdout)

--- a string representation of a type.
-- For tables and userdata with metatables, we assume that the metatable has a `_name`
-- field. If the field is not present it will return 'unknown table' or
-- 'unknown userdata'.
-- Lua file objects return the type 'file'.
-- @param obj an object
-- @return a string like 'number', 'table', 'file' or 'List'
function types.type (obj)
    local t = type(obj)
    if t == 'table' or t == 'userdata' then
        local mt = getmetatable(obj)
        if mt == fileMT then
            return 'file'
        elseif mt == nil then
            return t
        else
            -- TODO: the "unknown" is weird, it should just return the type
            return mt._name or "unknown "..t
        end
    else
        return t
    end
end

--- is this number an integer?
-- @param x a number
-- @raise error if x is not a number
-- @return boolean
function types.is_integer (x)
    return math_ceil(x)==x
end

--- Check if the object is "empty".
-- An object is considered empty if it is:
--
-- - `nil`
-- - a table without any items (key-value pairs or indexes)
-- - a string with no content ("")
-- - not a nil/table/string
-- @param o The object to check if it is empty.
-- @param ignore_spaces If the object is a string and this is true the string is
-- considered empty if it only contains spaces.
-- @return `true` if the object is empty, otherwise a falsy value.
function types.is_empty(o, ignore_spaces)
    if o == nil then
        return true
    elseif type(o) == "table" then
        return next(o) == nil
    elseif type(o) == "string" then
        return o == "" or (not not ignore_spaces and (not not o:find("^%s+$")))
    else
        return true
    end
end

local function check_meta (val)
    if type(val) == 'table' then return true end
    return getmetatable(val)
end

--- is an object 'array-like'?
-- An object is array like if:
--
-- - it is a table, or
-- - it has a metatable with `__len` and `__index` methods
--
-- NOTE: since `__len` is 5.2+, on 5.1 is usually returns `false` for userdata
-- @param val any value.
-- @return `true` if the object is array-like, otherwise a falsy value.
function types.is_indexable (val)
    local mt = check_meta(val)
    if mt == true then return true end
    return mt and mt.__len and mt.__index and true
end

--- can an object be iterated over with `pairs`?
-- An object is iterable if:
--
-- - it is a table, or
-- - it has a metatable with a `__pairs` meta method
--
-- NOTE: since `__pairs` is 5.2+, on 5.1 is usually returns `false` for userdata
-- @param val any value.
-- @return `true` if the object is iterable, otherwise a falsy value.
function types.is_iterable (val)
    local mt = check_meta(val)
    if mt == true then return true end
    return mt and mt.__pairs and true
end

--- can an object accept new key/pair values?
-- An object is iterable if:
--
-- - it is a table, or
-- - it has a metatable with a `__newindex` meta method
--
-- @param val any value.
-- @return `true` if the object is writeable, otherwise a falsy value.
function types.is_writeable (val)
    local mt = check_meta(val)
    if mt == true then return true end
    return mt and mt.__newindex and true
end

-- Strings that should evaluate to true.   -- TODO: add on/off ???
local trues = { yes=true, y=true, ["true"]=true, t=true, ["1"]=true }
-- Conditions types should evaluate to true.
local true_types = {
    boolean=function(o, true_strs, check_objs) return o end,
    string=function(o, true_strs, check_objs)
        o = o:lower()
        if trues[o] then
            return true
        end
        -- Check alternative user provided strings.
        for _,v in ipairs(true_strs or {}) do
            if type(v) == "string" and o == v:lower() then
                return true
            end
        end
        return false
    end,
    number=function(o, true_strs, check_objs) return o ~= 0 end,
    table=function(o, true_strs, check_objs) if check_objs and next(o) ~= nil then return true end return false end
}
--- Convert to a boolean value.
-- True values are:
--
-- * boolean: true.
-- * string: 'yes', 'y', 'true', 't', '1' or additional strings specified by `true_strs`.
-- * number: Any non-zero value.
-- * table: Is not empty and `check_objs` is true.
-- * everything else: Is not `nil` and `check_objs` is true.
--
-- @param o The object to evaluate.
-- @param[opt] true_strs optional Additional strings that when matched should evaluate to true. Comparison is case insensitive.
-- This should be a List of strings. E.g. "ja" to support German.
-- @param[opt] check_objs True if objects should be evaluated.
-- @return true if the input evaluates to true, otherwise false.
function types.to_bool(o, true_strs, check_objs)
    local true_func
    if true_strs then
        assert_arg(2, true_strs, "table")
    end
    true_func = true_types[type(o)]
    if true_func then
        return true_func(o, true_strs, check_objs)
    elseif check_objs and o ~= nil then
        return true
    end
    return false
end


return types

end,

["pl.url"] = function()
--------------------
-- Module: 'pl.url'
--------------------
--- Python-style URL quoting library.
--
-- @module pl.url

local url = {}

local function quote_char(c)
    return string.format("%%%02X", string.byte(c))
end

--- Quote the url, replacing special characters using the '%xx' escape.
-- @string s the string
-- @bool quote_plus Also escape slashes and replace spaces by plus signs.
-- @return The quoted string, or if `s` wasn't a string, just plain unaltered `s`.
function url.quote(s, quote_plus)
    if type(s) ~= "string" then
        return s
    end

    s = s:gsub("\n", "\r\n")
    s = s:gsub("([^A-Za-z0-9 %-_%./])", quote_char)
    if quote_plus then
        s = s:gsub(" ", "+")
        s = s:gsub("/", quote_char)
    else
        s = s:gsub(" ", "%%20")
    end

    return s
end

local function unquote_char(h)
    return string.char(tonumber(h, 16))
end

--- Unquote the url, replacing '%xx' escapes and plus signs.
-- @string s the string
-- @return The unquoted string, or if `s` wasn't a string, just plain unaltered `s`.
function url.unquote(s)
    if type(s) ~= "string" then
        return s
    end

    s = s:gsub("+", " ")
    s = s:gsub("%%(%x%x)", unquote_char)
    s = s:gsub("\r\n", "\n")

    return s
end

return url

end,

["pl.utils"] = function()
--------------------
-- Module: 'pl.utils'
--------------------
--- Generally useful routines.
-- See  @{01-introduction.md.Generally_useful_functions|the Guide}.
--
-- Dependencies: `pl.compat`, all exported fields and functions from
-- `pl.compat` are also available in this module.
--
-- @module pl.utils
local format = string.format
local compat = require 'pl.compat'
local stdout = io.stdout
local append = table.insert
local concat = table.concat
local _unpack = table.unpack  -- always injected by 'compat'
local find = string.find
local sub = string.sub

local is_windows = compat.is_windows
local err_mode = 'default'
local raise
local operators
local _function_factories = {}


local utils = { _VERSION = "1.12.0" }
for k, v in pairs(compat) do utils[k] = v  end

--- Some standard patterns
-- @table patterns
utils.patterns = {
    FLOAT = '[%+%-%d]%d*%.?%d*[eE]?[%+%-]?%d*', -- floating point number
    INTEGER = '[+%-%d]%d*',                     -- integer number
    IDEN = '[%a_][%w_]*',                       -- identifier
    FILE = '[%a%.\\][:%][%w%._%-\\]*',          -- file
}


--- Standard meta-tables as used by other Penlight modules
-- @table stdmt
-- @field List the List metatable
-- @field Map the Map metatable
-- @field Set the Set metatable
-- @field MultiMap the MultiMap metatable
utils.stdmt = {
    List = {_name='List'},
    Map = {_name='Map'},
    Set = {_name='Set'},
    MultiMap = {_name='MultiMap'},
}


--- pack an argument list into a table.
-- @param ... any arguments
-- @return a table with field `n` set to the length
-- @function utils.pack
-- @see compat.pack
-- @see utils.npairs
-- @see utils.unpack
utils.pack = table.pack  -- added here to be symmetrical with unpack

--- unpack a table and return its contents.
--
-- NOTE: this implementation differs from the Lua implementation in the way
-- that this one DOES honor the `n` field in the table `t`, such that it is 'nil-safe'.
-- @param t table to unpack
-- @param[opt] i index from which to start unpacking, defaults to 1
-- @param[opt] j index of the last element to unpack, defaults to `t.n` or else `#t`
-- @return multiple return values from the table
-- @function utils.unpack
-- @see compat.unpack
-- @see utils.pack
-- @see utils.npairs
-- @usage
-- local t = table.pack(nil, nil, nil, 4)
-- local a, b, c, d = table.unpack(t)   -- this `unpack` is NOT nil-safe, so d == nil
--
-- local a, b, c, d = utils.unpack(t)   -- this is nil-safe, so d == 4
function utils.unpack(t, i, j)
    return _unpack(t, i or 1, j or t.n or #t)
end

--- print an arbitrary number of arguments using a format.
-- Output will be sent to `stdout`.
-- @param fmt The format (see `string.format`)
-- @param ... Extra arguments for format
function utils.printf(fmt, ...)
    utils.assert_string(1, fmt)
    utils.fprintf(stdout, fmt, ...)
end

--- write an arbitrary number of arguments to a file using a format.
-- @param f File handle to write to.
-- @param fmt The format (see `string.format`).
-- @param ... Extra arguments for format
function utils.fprintf(f,fmt,...)
    utils.assert_string(2,fmt)
    f:write(format(fmt,...))
end

do
    local function import_symbol(T,k,v,libname)
        local key = rawget(T,k)
        -- warn about collisions!
        if key and k ~= '_M' and k ~= '_NAME' and k ~= '_PACKAGE' and k ~= '_VERSION' then
            utils.fprintf(io.stderr,"warning: '%s.%s' will not override existing symbol\n",libname,k)
            return
        end
        rawset(T,k,v)
    end

    local function lookup_lib(T,t)
        for k,v in pairs(T) do
            if v == t then return k end
        end
        return '?'
    end

    local already_imported = {}

    --- take a table and 'inject' it into the local namespace.
    -- @param t The table (table), or module name (string), defaults to this `utils` module table
    -- @param T An optional destination table (defaults to callers environment)
    function utils.import(t,T)
        T = T or _G
        t = t or utils
        if type(t) == 'string' then
            t = require (t)
        end
        local libname = lookup_lib(T,t)
        if already_imported[t] then return end
        already_imported[t] = libname
        for k,v in pairs(t) do
            import_symbol(T,k,v,libname)
        end
    end
end

--- return either of two values, depending on a condition.
-- @param cond A condition
-- @param value1 Value returned if cond is truthy
-- @param value2 Value returned if cond is falsy
function utils.choose(cond, value1, value2)
    return cond and value1 or value2
end

--- convert an array of values to strings.
-- @param t a list-like table
-- @param[opt] temp (table) buffer to use, otherwise allocate
-- @param[opt] tostr custom tostring function, called with (value,index). Defaults to `tostring`.
-- @return the converted buffer
function utils.array_tostring (t,temp,tostr)
    temp, tostr = temp or {}, tostr or tostring
    for i = 1,#t do
        temp[i] = tostr(t[i],i)
    end
    return temp
end



--- is the object of the specified type?
-- If the type is a string, then use type, otherwise compare with metatable
-- @param obj An object to check
-- @param tp String of what type it should be
-- @return boolean
-- @usage utils.is_type("hello world", "string")   --> true
-- -- or check metatable
-- local my_mt = {}
-- local my_obj = setmetatable(my_obj, my_mt)
-- utils.is_type(my_obj, my_mt)  --> true
function utils.is_type (obj,tp)
    if type(tp) == 'string' then return type(obj) == tp end
    local mt = getmetatable(obj)
    return tp == mt
end



--- an iterator with indices, similar to `ipairs`, but with a range.
-- This is a nil-safe index based iterator that will return `nil` when there
-- is a hole in a list. To be safe ensure that table `t.n` contains the length.
-- @tparam table t the table to iterate over
-- @tparam[opt=1] integer i_start start index
-- @tparam[opt=t.n or #t] integer i_end end index
-- @tparam[opt=1] integer step step size
-- @treturn integer index
-- @treturn any value at index (which can be `nil`!)
-- @see utils.pack
-- @see utils.unpack
-- @usage
-- local t = utils.pack(nil, 123, nil)  -- adds an `n` field when packing
--
-- for i, v in utils.npairs(t, 2) do  -- start at index 2
--   t[i] = tostring(t[i])
-- end
--
-- -- t = { n = 3, [2] = "123", [3] = "nil" }
function utils.npairs(t, i_start, i_end, step)
  step = step or 1
  if step == 0 then
    error("iterator step-size cannot be 0", 2)
  end
  local i = (i_start or 1) - step
  i_end = i_end or t.n or #t
  if step < 0 then
    return function()
      i = i + step
      if i < i_end then
        return nil
      end
      return i, t[i]
    end

  else
    return function()
      i = i + step
      if i > i_end then
        return nil
      end
      return i, t[i]
    end
  end
end



--- Error handling
-- @section Error-handling

--- assert that the given argument is in fact of the correct type.
-- @param n argument index
-- @param val the value
-- @param tp the type
-- @param verify an optional verification function
-- @param msg an optional custom message
-- @param lev optional stack position for trace, default 2
-- @return the validated value
-- @raise if `val` is not the correct type
-- @usage
-- local param1 = assert_arg(1,"hello",'table')  --> error: argument 1 expected a 'table', got a 'string'
-- local param4 = assert_arg(4,'!@#$%^&*','string',path.isdir,'not a directory')
--      --> error: argument 4: '!@#$%^&*' not a directory
function utils.assert_arg (n,val,tp,verify,msg,lev)
    if type(val) ~= tp then
        error(("argument %d expected a '%s', got a '%s'"):format(n,tp,type(val)),lev or 2)
    end
    if verify and not verify(val) then
        error(("argument %d: '%s' %s"):format(n,val,msg),lev or 2)
    end
    return val
end

--- creates an Enum table.
-- This helps prevent magic strings in code by throwing errors for accessing
-- non-existing values.
--
-- Calling on the object does the same, but returns a soft error; `nil + err`.
--
-- The values are equal to the keys. The enum object is
-- read-only.
-- @param ... strings that make up the enumeration.
-- @return Enum object
-- @usage -- accessing at runtime
-- local obj = {}
-- obj.MOVEMENT = utils.enum("FORWARD", "REVERSE", "LEFT", "RIGHT")
--
-- if current_movement == obj.MOVEMENT.FORWARD then
--   -- do something
--
-- elseif current_movement == obj.MOVEMENT.REVERES then
--   -- throws error due to typo 'REVERES', so a silent mistake becomes a hard error
--   -- "'REVERES' is not a valid value (expected one of: 'FORWARD', 'REVERSE', 'LEFT', 'RIGHT')"
--
-- end
-- @usage -- validating user-input
-- local parameter = "...some user provided option..."
-- local ok, err = obj.MOVEMENT(parameter) -- calling on the object
-- if not ok then
--   print("bad 'parameter', " .. err)
--   os.exit(1)
-- end
function utils.enum(...)
  local lst = utils.pack(...)
  utils.assert_arg(1, lst[1], "string") -- at least 1 string

  local enum = {}
  for i, value in ipairs(lst) do
    utils.assert_arg(i, value, "string")
    enum[value] = value
  end

  local valid = "(expected one of: '" .. concat(lst, "', '") .. "')"
  setmetatable(enum, {
    __index = function(self, key)
      error(("'%s' is not a valid value %s"):format(tostring(key), valid), 2)
    end,
    __newindex = function(self, key, value)
      error("the Enum object is read-only", 2)
    end,
    __call = function(self, key)
      if type(key) == "string" then
        local v = rawget(self, key)
        if v then
          return v
        end
      end
      return nil, ("'%s' is not a valid value %s"):format(tostring(key), valid)
    end
  })

  return enum
end


--- process a function argument.
-- This is used throughout Penlight and defines what is meant by a function:
-- Something that is callable, or an operator string as defined by <code>pl.operator</code>,
-- such as '>' or '#'. If a function factory has been registered for the type, it will
-- be called to get the function.
-- @param idx argument index
-- @param f a function, operator string, or callable object
-- @param msg optional error message
-- @return a callable
-- @raise if idx is not a number or if f is not callable
function utils.function_arg (idx,f,msg)
    utils.assert_arg(1,idx,'number')
    local tp = type(f)
    if tp == 'function' then return f end  -- no worries!
    -- ok, a string can correspond to an operator (like '==')
    if tp == 'string' then
        if not operators then operators = require 'pl.operator'.optable end
        local fn = operators[f]
        if fn then return fn end
        local fn, err = utils.string_lambda(f)
        if not fn then error(err..': '..f) end
        return fn
    elseif tp == 'table' or tp == 'userdata' then
        local mt = getmetatable(f)
        if not mt then error('not a callable object',2) end
        local ff = _function_factories[mt]
        if not ff then
            if not mt.__call then error('not a callable object',2) end
            return f
        else
            return ff(f) -- we have a function factory for this type!
        end
    end
    if not msg then msg = " must be callable" end
    if idx > 0 then
        error("argument "..idx..": "..msg,2)
    else
        error(msg,2)
    end
end


--- assert the common case that the argument is a string.
-- @param n argument index
-- @param val a value that must be a string
-- @return the validated value
-- @raise val must be a string
-- @usage
-- local val = 42
-- local param2 = utils.assert_string(2, val) --> error: argument 2 expected a 'string', got a 'number'
function utils.assert_string (n, val)
    return utils.assert_arg(n,val,'string',nil,nil,3)
end

--- control the error strategy used by Penlight.
-- This is a global setting that controls how `utils.raise` behaves:
--
-- - 'default': return `nil + error` (this is the default)
-- - 'error': throw a Lua error
-- - 'quit': exit the program
--
-- @param mode either 'default', 'quit'  or 'error'
-- @see utils.raise
function utils.on_error (mode)
    mode = tostring(mode)
    if ({['default'] = 1, ['quit'] = 2, ['error'] = 3})[mode] then
      err_mode = mode
    else
      -- fail loudly
      local err = "Bad argument expected string; 'default', 'quit', or 'error'. Got '"..tostring(mode).."'"
      if err_mode == 'default' then
        error(err, 2)  -- even in 'default' mode fail loud in this case
      end
      raise(err)
    end
end

--- used by Penlight functions to return errors. Its global behaviour is controlled
-- by `utils.on_error`.
-- To use this function you MUST use it in conjunction with `return`, since it might
-- return `nil + error`.
-- @param err the error string.
-- @see utils.on_error
-- @usage
-- if some_condition then
--   return utils.raise("some condition was not met")  -- MUST use 'return'!
-- end
function utils.raise (err)
    if err_mode == 'default' then
        return nil, err
    elseif err_mode == 'quit' then
        return utils.quit(err)
    else
        error(err, 2)
    end
end
raise = utils.raise



--- File handling
-- @section files

--- return the contents of a file as a string
-- @param filename The file path
-- @param is_bin open in binary mode
-- @return file contents
function utils.readfile(filename,is_bin)
    local mode = is_bin and 'b' or ''
    utils.assert_string(1,filename)
    local f,open_err = io.open(filename,'r'..mode)
    if not f then return raise (open_err) end
    local res,read_err = f:read('*a')
    f:close()
    if not res then
        -- Errors in io.open have "filename: " prefix,
        -- error in file:read don't, add it.
        return raise (filename..": "..read_err)
    end
    return res
end

--- write a string to a file
-- @param filename The file path
-- @param str The string
-- @param is_bin open in binary mode
-- @return true or nil
-- @return error message
-- @raise error if filename or str aren't strings
function utils.writefile(filename,str,is_bin)
    local mode = is_bin and 'b' or ''
    utils.assert_string(1,filename)
    utils.assert_string(2,str)
    local f,err = io.open(filename,'w'..mode)
    if not f then return raise(err) end
    local ok, write_err = f:write(str)
    f:close()
    if not ok then
        -- Errors in io.open have "filename: " prefix,
        -- error in file:write don't, add it.
        return raise (filename..": "..write_err)
    end
    return true
end

--- return the contents of a file as a list of lines
-- @param filename The file path
-- @return file contents as a table
-- @raise error if filename is not a string
function utils.readlines(filename)
    utils.assert_string(1,filename)
    local f,err = io.open(filename,'r')
    if not f then return raise(err) end
    local res = {}
    for line in f:lines() do
        append(res,line)
    end
    f:close()
    return res
end

--- OS functions
-- @section OS-functions

--- execute a shell command and return the output.
-- This function redirects the output to tempfiles and returns the content of those files.
-- @param cmd a shell command
-- @param bin boolean, if true, read output as binary file
-- @return true if successful
-- @return actual return code
-- @return stdout output (string)
-- @return errout output (string)
function utils.executeex(cmd, bin)
    local outfile = os.tmpname()
    local errfile = os.tmpname()

    if is_windows and not outfile:find(':') then
        outfile = os.getenv('TEMP')..outfile
        errfile = os.getenv('TEMP')..errfile
    end
    cmd = cmd .. " > " .. utils.quote_arg(outfile) .. " 2> " .. utils.quote_arg(errfile)

    local success, retcode = utils.execute(cmd)
    local outcontent = utils.readfile(outfile, bin)
    local errcontent = utils.readfile(errfile, bin)
    os.remove(outfile)
    os.remove(errfile)
    return success, retcode, (outcontent or ""), (errcontent or "")
end

--- Quote and escape an argument of a command.
-- Quotes a single (or list of) argument(s) of a command to be passed
-- to `os.execute`, `pl.utils.execute` or `pl.utils.executeex`.
-- @param argument (string or table/list) the argument to quote. If a list then
-- all arguments in the list will be returned as a single string quoted.
-- @return quoted and escaped argument.
-- @usage
-- local options = utils.quote_arg {
--     "-lluacov",
--     "-e",
--     "utils = print(require('pl.utils')._VERSION",
-- }
-- -- returns: -lluacov -e 'utils = print(require('\''pl.utils'\'')._VERSION'
function utils.quote_arg(argument)
    if type(argument) == "table" then
        -- encode an entire table
        local r = {}
        for i, arg in ipairs(argument) do
            r[i] = utils.quote_arg(arg)
        end

        return concat(r, " ")
    end
    -- only a single argument
    if is_windows then
        if argument == "" or argument:find('[ \f\t\v]') then
            -- Need to quote the argument.
            -- Quotes need to be escaped with backslashes;
            -- additionally, backslashes before a quote, escaped or not,
            -- need to be doubled.
            -- See documentation for CommandLineToArgvW Windows function.
            argument = '"' .. argument:gsub([[(\*)"]], [[%1%1\"]]):gsub([[\+$]], "%0%0") .. '"'
        end

        -- os.execute() uses system() C function, which on Windows passes command
        -- to cmd.exe. Escape its special characters.
        return (argument:gsub('["^<>!|&%%]', "^%0"))
    else
        if argument == "" or argument:find('[^a-zA-Z0-9_@%+=:,./-]') then
            -- To quote arguments on posix-like systems use single quotes.
            -- To represent an embedded single quote close quoted string ('),
            -- add escaped quote (\'), open quoted string again (').
            argument = "'" .. argument:gsub("'", [['\'']]) .. "'"
        end

        return argument
    end
end

--- error out of this program gracefully.
-- @param[opt] code The exit code, defaults to -`1` if omitted
-- @param msg The exit message will be sent to `stderr` (will be formatted with the extra parameters)
-- @param ... extra arguments for message's format'
-- @see utils.fprintf
-- @usage utils.quit(-1, "Error '%s' happened", "42")
-- -- is equivalent to
-- utils.quit("Error '%s' happened", "42")  --> Error '42' happened
function utils.quit(code, msg, ...)
    if type(code) == 'string' then
        utils.fprintf(io.stderr, code, msg, ...)
        io.stderr:write('\n')
        code = -1 -- TODO: this is odd, see the test. Which returns 255 as exit code
    elseif msg then
        utils.fprintf(io.stderr, msg, ...)
        io.stderr:write('\n')
    end
    os.exit(code, true)
end


--- String functions
-- @section string-functions

--- escape any Lua 'magic' characters in a string
-- @param s The input string
function utils.escape(s)
    utils.assert_string(1,s)
    return (s:gsub('[%-%.%+%[%]%(%)%$%^%%%?%*]','%%%1'))
end

--- split a string into a list of strings separated by a delimiter.
-- @param s The input string
-- @param re optional A Lua string pattern; defaults to '%s+'
-- @param plain optional If truthy don't use Lua patterns
-- @param n optional maximum number of elements (if there are more, the last will remian un-split)
-- @return a list-like table
-- @raise error if s is not a string
-- @see splitv
function utils.split(s,re,plain,n)
    utils.assert_string(1,s)
    local i1,ls = 1,{}
    if not re then re = '%s+' end
    if re == '' then return {s} end
    while true do
        local i2,i3 = find(s,re,i1,plain)
        if not i2 then
            local last = sub(s,i1)
            if last ~= '' then append(ls,last) end
            if #ls == 1 and ls[1] == '' then
                return {}
            else
                return ls
            end
        end
        append(ls,sub(s,i1,i2-1))
        if n and #ls == n then
            ls[#ls] = sub(s,i1)
            return ls
        end
        i1 = i3+1
    end
end

--- split a string into a number of return values.
-- Identical to `split` but returns multiple sub-strings instead of
-- a single list of sub-strings.
-- @param s the string
-- @param re A Lua string pattern; defaults to '%s+'
-- @param plain don't use Lua patterns
-- @param n optional maximum number of splits
-- @return n values
-- @usage first,next = splitv('user=jane=doe','=', false, 2)
-- assert(first == "user")
-- assert(next == "jane=doe")
-- @see split
function utils.splitv (s,re, plain, n)
    return _unpack(utils.split(s,re, plain, n))
end


--- Functional
-- @section functional


--- 'memoize' a function (cache returned value for next call).
-- This is useful if you have a function which is relatively expensive,
-- but you don't know in advance what values will be required, so
-- building a table upfront is wasteful/impossible.
-- @param func a function of at least one argument
-- @return a function with at least one argument, which is used as the key.
function utils.memoize(func)
    local cache = {}
    return function(k)
        local res = cache[k]
        if res == nil then
            res = func(k)
            cache[k] = res
        end
        return res
    end
end


--- associate a function factory with a type.
-- A function factory takes an object of the given type and
-- returns a function for evaluating it
-- @tab mt metatable
-- @func fun a callable that returns a function
function utils.add_function_factory (mt,fun)
    _function_factories[mt] = fun
end

local function _string_lambda(f)
    if f:find '^|' or f:find '_' then
        local args,body = f:match '|([^|]*)|(.+)'
        if f:find '_' then
            args = '_'
            body = f
        else
            if not args then return raise 'bad string lambda' end
        end
        local fstr = 'return function('..args..') return '..body..' end'
        local fn,err = utils.load(fstr)
        if not fn then return raise(err) end
        fn = fn()
        return fn
    else
        return raise 'not a string lambda'
    end
end


--- an anonymous function as a string. This string is either of the form
-- '|args| expression' or is a function of one argument, '_'
-- @param lf function as a string
-- @return a function
-- @function utils.string_lambda
-- @usage
-- string_lambda '|x|x+1' (2) == 3
-- string_lambda '_+1' (2) == 3
utils.string_lambda = utils.memoize(_string_lambda)


--- bind the first argument of the function to a value.
-- @param fn a function of at least two values (may be an operator string)
-- @param p a value
-- @return a function such that f(x) is fn(p,x)
-- @raise same as @{function_arg}
-- @see func.bind1
-- @usage local function f(msg, name)
--   print(msg .. " " .. name)
-- end
--
-- local hello = utils.bind1(f, "Hello")
--
-- print(hello("world"))     --> "Hello world"
-- print(hello("sunshine"))  --> "Hello sunshine"
function utils.bind1 (fn,p)
    fn = utils.function_arg(1,fn)
    return function(...) return fn(p,...) end
end


--- bind the second argument of the function to a value.
-- @param fn a function of at least two values (may be an operator string)
-- @param p a value
-- @return a function such that f(x) is fn(x,p)
-- @raise same as @{function_arg}
-- @usage local function f(a, b, c)
--   print(a .. " " .. b .. " " .. c)
-- end
--
-- local hello = utils.bind1(f, "world")
--
-- print(hello("Hello", "!"))  --> "Hello world !"
-- print(hello("Bye", "?"))    --> "Bye world ?"
function utils.bind2 (fn,p)
    fn = utils.function_arg(1,fn)
    return function(x,...) return fn(x,p,...) end
end




--- Deprecation
-- @section deprecation

do
  -- the default implementation
  local deprecation_func = function(msg, trace)
    if trace then
      warn(msg, "\n", trace)  -- luacheck: ignore
    else
      warn(msg)  -- luacheck: ignore
    end
  end

  --- Sets a deprecation warning function.
  -- An application can override this function to support proper output of
  -- deprecation warnings. The warnings can be generated from libraries or
  -- functions by calling `utils.raise_deprecation`. The default function
  -- will write to the 'warn' system (introduced in Lua 5.4, or the compatibility
  -- function from the `compat` module for earlier versions).
  --
  -- Note: only applications should set/change this function, libraries should not.
  -- @param func a callback with signature: `function(msg, trace)` both arguments are strings, the latter being optional.
  -- @see utils.raise_deprecation
  -- @usage
  -- -- write to the Nginx logs with OpenResty
  -- utils.set_deprecation_func(function(msg, trace)
  --   ngx.log(ngx.WARN, msg, (trace and (" " .. trace) or nil))
  -- end)
  --
  -- -- disable deprecation warnings
  -- utils.set_deprecation_func()
  function utils.set_deprecation_func(func)
    if func == nil then
      deprecation_func = function() end
    else
      utils.assert_arg(1, func, "function")
      deprecation_func = func
    end
  end

  --- raises a deprecation warning.
  -- For options see the usage example below.
  --
  -- Note: the `opts.deprecated_after` field is the last version in which
  -- a feature or option was NOT YET deprecated! Because when writing the code it
  -- is quite often not known in what version the code will land. But the last
  -- released version is usually known.
  -- @param opts options table
  -- @see utils.set_deprecation_func
  -- @usage
  -- warn("@on")   -- enable Lua warnings, they are usually off by default
  --
  -- function stringx.islower(str)
  --   raise_deprecation {
  --     source = "Penlight " .. utils._VERSION,                   -- optional
  --     message = "function 'islower' was renamed to 'is_lower'", -- required
  --     version_removed = "2.0.0",                                -- optional
  --     deprecated_after = "1.2.3",                               -- optional
  --     no_trace = true,                                          -- optional
  --   }
  --   return stringx.is_lower(str)
  -- end
  -- -- output: "[Penlight 1.9.2] function 'islower' was renamed to 'is_lower' (deprecated after 1.2.3, scheduled for removal in 2.0.0)"
  function utils.raise_deprecation(opts)
    utils.assert_arg(1, opts, "table")
    if type(opts.message) ~= "string" then
      error("field 'message' of the options table must be a string", 2)
    end
    local trace
    if not opts.no_trace then
      trace = debug.traceback("", 2):match("[\n%s]*(.-)$")
    end
    local msg
    if opts.deprecated_after and opts.version_removed then
      msg = (" (deprecated after %s, scheduled for removal in %s)"):format(
        tostring(opts.deprecated_after), tostring(opts.version_removed))
    elseif opts.deprecated_after then
      msg = (" (deprecated after %s)"):format(tostring(opts.deprecated_after))
    elseif opts.version_removed then
      msg = (" (scheduled for removal in %s)"):format(tostring(opts.version_removed))
    else
      msg = ""
    end

    msg = opts.message .. msg

    if opts.source then
      msg = "[" .. opts.source .."] " .. msg
    else
      if msg:sub(1,1) == "@" then
        -- in Lua 5.4 "@" prefixed messages are control messages to the warn system
        error("message cannot start with '@'", 2)
      end
    end

    deprecation_func(msg, trace)
  end

end


return utils



end,

----------------------
-- Modules part end --
----------------------
        }
        if files[path] then
            return files[path]
        else
            return origin_seacher(path)
        end
    end
end
---------------------------------------------------------
----------------Auto generated code block----------------
---------------------------------------------------------
return require('pl.import_into')()