summaryrefslogtreecommitdiff
path: root/Master/texmf-dist/source/latex/babel/babel.dtx
blob: 236d513ef3cc67727b7d229ba27e091bac3660e6 (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
% \iffalse meta-comment
%
% Copyright 2012-2013 Javier Bezos and Johannes L. Braams.
% Copyright 1989-2012 Johannes L. Braams and any individual authors
% listed elsewhere in this file. 
% All rights reserved.
% 
% This file is part of the Babel system.
% --------------------------------------
% 
% It may be distributed and/or modified under the
% conditions of the LaTeX Project Public License, either version 1.3
% of this license or (at your option) any later version.
% The latest version of this license is in
%   http://www.latex-project.org/lppl.txt
% and version 1.3 or later is part of all distributions of LaTeX
% version 2003/12/01 or later.
% 
% This work has the LPPL maintenance status "maintained".
% 
% The Current Maintainer of this work is Javier Bezos.
% 
% The list of all files belonging to the Babel system is
% given in the file `manifest.bbl. See also `legal.bbl' for additional
% information.
% 
% The list of derived (unpacked) files belonging to the distribution
% and covered by LPPL is defined by the unpacking scripts (with
% extension |.ins|) which are part of the distribution.
% \fi
% \CheckSum{5011}
%
% \def\filename{babel.dtx}
% \let\thisfilename\filename
%
%\iffalse
%% File 'babel.dtx'
%\fi
%%\ProvidesFile{babel.dtx}[2014/09/25 v3.9l The Babel package]
%\iffalse
%
% Babel DOCUMENT-STYLE option for LaTeX version 2.09 or plain TeX;
%% Babel package for LaTeX2e.
%
%% Copyright (C) 1989-2008 by Johannes Braams,
%%                            TeXniek
%%                            all rights reserved.
%% Copyright (C) 2013-2014 by Johannes Braams
%%                            TeXniek
%%                            by Javier Bezos
%%                            all rights reserved.
%
%<*filedriver>
\documentclass{ltxdoc}
\usepackage{bera}
\raggedright
\addtolength{\textwidth}{25pt}
\addtolength{\textheight}{3.5cm}
\addtolength{\topmargin}{-2cm}
\font\manual=logo10 % font used for the METAFONT logo, etc.
\newcommand*\MF{{\manual META}\-{\manual FONT}}
\newcommand*\babel{\textsf{babel}}
\newcommand*\Babel{\textsf{Babel}}
\newcommand*\xetex{\textsf{xetex}}
\newcommand*\luatex{\textsf{luatex}}
\newcommand*\nb[1]{}
\newcommand*\m[1]{\mbox{$\langle$\normalfont\itshape#1\/$\rangle$}}
\newcommand*\langlist{%
  \meta{language}\texttt{,}\meta{language}\texttt{,}...}
\newcommand*\langvar{\m{lang}}
\newcommand*\note[1]{}
\newcommand*\bsl{\protect\bslash}
\newcommand*\Lopt[1]{\textsf{#1}}
\newcommand*\Lenv[1]{\textsf{#1}}
\newcommand*\menv[1]{\char`\{#1\char`\}}
\newcommand*\Eenv[1]{%
  \quad\ldots\quad   
  \texttt{\color{thered}\string\end\menv{#1}}}
\newcommand*\file[1]{\texttt{#1}}
\newcommand*\cls[1]{\texttt{#1}}
\newcommand*\pkg[1]{\texttt{#1}}
\addtolength{\oddsidemargin}{1em}
% Stolen and adapted from microtype:
\usepackage{color,colortbl}
\newcommand\New[1]{%
  \colorbox[rgb]{.92, .86, .73}{New #1}\enspace\ignorespaces}
\definecolor{thered}  {rgb}{0.65,0.04,0.07}
\definecolor{thegreen}{rgb}{0.06,0.44,0.08}
\definecolor{thegrey} {gray}{0.8}
\definecolor{theshade}{rgb}{1,1,0.97}
\definecolor{theframe}{gray}{0.6}
\definecolor{lightgray}{gray}{0.95}
\IfFileExists{listings.sty}{
  \usepackage{listings}
  \lstset{
    % gobble=1,
    columns=flexible,
    keepspaces,
    basicstyle=\MacroFont,
    keywords=[0]{\selectlanguage,\foreignlanguage,\defineshorthand,
     \babelhyphen,\babelhyphenation,\spanishhyphenmins,\addto,
     \StartBabelCommands,\SetString,\EndBabelCommands,\shorthandoff,
     \languageshorthands,\useshorthands,\AddBabelHook,\SetStringLoop,
     \SetCase,\AfterBabelLanguage,\SetHyphenMap,\BabelLowerMM,
     \babelensure,\babeltags},
    keywordstyle=[0]\color{thered},
    keywords=[1]{ngerman,italian,dutch,english,main,esperanto,
     frenchb,shorthands,extrasfrench,extrasrussian,extrasenglish,
     stringprocess,afterextras,latin,medieval,spanish,notilde,
     lcroman,danish},
    keywordstyle=[1]\color{thegreen},
    comment=[l]\%,
    commentstyle=\color{thegrey}\itshape,
    alsoother={0123456789_},
    frame=single,
    backgroundcolor=\color{theshade},
    rulecolor=\color{theframe},
    framerule=\fboxrule,
  }
  \let\verbatim\relax
  \lstnewenvironment{verbatim}[1][]{\lstset{##1}}{}
}{}
\def\PrintDescribeMacro#1{%
  \strut\MacroFont\color{thered}\normalsize\string#1}
\def\Describe#1{%
  \par\penalty-500\vskip3ex\noindent
  \DescribeMacro{#1}\args}
\def\DescribeOther{\vskip-4ex\Describe}
\makeatletter
\def\args#1{%
  \def\bbl@tempa{#1}%
  \ifx\bbl@tempa\@empty\else#1\vskip1ex\fi\ignorespaces}
\begingroup % Changes to ltxdoc
  \catcode`\<\active
  \catcode`\>\active
  \gdef\check@plus@etc{%
    \let\bbl@next\pm@module
    \ifx*\next
      \let\bbl@next\star@module
    \else\ifx/\next
      \let\bbl@next\slash@module
    \else\ifx<\next
      \let\bbl@next\var@module
    \fi\fi\fi
    \bbl@next}
  \gdef\var@module#1#2#3>>{%
    $\langle$\pm@module#2#3>$\rangle$%
    \ifx*#2\ $\equiv$\fi}
\endgroup
\renewcommand*\l@section[2]{%
  \ifnum \c@tocdepth >\z@
    \addpenalty\@secpenalty
    \addvspace{1.0em \@plus\p@}%
    \setlength\@tempdima{2em}%
    \begingroup
      \parindent \z@ \rightskip \@pnumwidth
      \parfillskip -\@pnumwidth
      \leavevmode \bfseries
      \advance\leftskip\@tempdima
      \hskip -\leftskip
      #1\nobreak\hfil \nobreak\hb@xt@\@pnumwidth{\hss #2}\par
    \endgroup
  \fi}
\renewcommand*\l@subsection{\@dottedtocline{2}{2em}{3em}}
\renewcommand*\l@subsubsection{\@dottedtocline{3}{5em}{4em}}
\renewcommand*\l@paragraph{\@dottedtocline{4}{9em}{4.5em}}
\renewcommand\partname{Part}
\makeatother
\begin{document}
\title{Babel, a multilingual package for use with \LaTeX's standard
   document classes\thanks{During the development ideas from Nico
   Poppelier, Piet van Oostrum and many others have been used.
   Bernd Raichle has provided many helpful suggestions.}}
\author{Johannes Braams\\
        Kersengaarde 33\\
        2723 BP Zoetermeer\\
        The Netherlands\\
        \normalsize For version 3.9, Javier Bezos\\
        \normalsize \texttt{www.tex-tipografia.com}}

\date{Typeset \today}
\begin{titlepage}
\begin{minipage}[t][0pt]{30cm}
\vspace{-3cm}\hspace{-7cm}
\sffamily
\begin{tabular}{p{8cm}p{15cm}}
\cellcolor[rgb]{.86,.73,.67}
&\cellcolor[rgb]{.95,.95,.95}
\vspace{3.6cm}%
\color[rgb]{.55,.4,.35}
\leftskip5mm
\sffamily\fontsize{72}{72}\selectfont Babel
\vspace{1.8cm}
\\
\cellcolor[rgb]{.95,.95,.95}
\vspace{2cm}\hspace{1.5cm}
\begin{minipage}{5cm}
\Large
Version 3.9l\newline
2014/09/25

\vspace{1cm}
\textit{Original author}\newline
Johannes L. Braams

\vspace{.3cm}
\textit{Current maintainer}\newline
Javier Bezos
\end{minipage}
&\cellcolor[rgb]{.92, .86, .73}
\vspace{2cm}
\leftskip5mm
\begin{minipage}{10cm}
\large\setlength\parskip{3mm}\raggedright
  The standard distribution of \LaTeX\ contains a number of document
  classes that are meant to be used, but also serve as examples for
  other users to create their own document classes.  These document
  classes have become very popular among \LaTeX\ users. But it should
  be kept in mind that they were designed for American tastes and
  typography. At one time they even contained a number of hard-wired
  texts.
  
  This manual describes \babel{}, a package that makes use of the
  capabilities of \TeX\ version 3 and, to some extent, \xetex{} and
  \luatex, to provide an environment in which documents can be typeset
  in a language other than US English, or in more than one language or
  script.
  However, no attempt has been done to take full advantage of the
  features provided by the latter, which would require a completely
  new core (as for example \file{polyglossia} or as part of \LaTeX3).
  \vspace{20cm}
\end{minipage}
\end{tabular}
\end{minipage}
\end{titlepage}

\tableofcontents
\clearpage

\part{User guide}

\section{The user interface}\label{U-I}

The basic user interface of this package is quite simple. It consists
of a set of commands that switch from one language to another, and a
set of commands that deal with shorthands. It is also possible to find
out what the current language is.

In most cases, a single language is required, and then all you need in
\LaTeX{} is to load the package using its standand mechanism for this
purpose, namely, passing that language as an optional argument.

In multilingual documents, just use several option. So, in \LaTeX2e\
the preamble of the document:
\begin{verbatim}
\documentclass{article}
\usepackage[dutch,english]{babel}
\end{verbatim}
would tell \LaTeX\ that the document would be written in two
languages, Dutch and English, and that English would be the first
language in use, and the main one. You can also set the main language
explicitly:
\begin{verbatim}
\documentclass{article}
\usepackage[main=english,dutch]{babel}
\end{verbatim}
Another approach is making \Lopt{dutch} and \Lopt{english} global
options in order to let other packages detect and use them:

\begin{verbatim}
\documentclass[dutch,english]{article}
\usepackage{babel}
\usepackage{varioref}
\end{verbatim}

In this last example, the package \texttt{varioref} will also see
the options and will be able to use them.

Languages may be set as global and as package option at the same
time, but in such a case you should set explicitly the main language
with the package option |main|:
\begin{verbatim}
\documentclass[italian]{book}
\usepackage[ngerman,main=italian]{babel}
\end{verbatim}

\New{3.9c} The basic behaviour of some languages can be modified when
loading \babel{} by means of \textit{modifiers}. They are set after
the language name, and are prefixed with a dot (only when the language
is set as package option -- neither global options nor the |main| key
accept them). An example is (spaces are not significant and they can
be added or removed):\footnote{No predefined ``axis'' for modifiers
are provided because languages and their scripts have quite different
needs.}
\begin{verbatim}
\usepackage[latin.medieval, spanish.notilde.lcroman, danish]{babel}
\end{verbatim}

Attributes (described below) are considered modifiers, ie, you can
set an attribute by including it in the list of modifiers. However,
modifiers is a more general mechanism.

Because of the way \babel{} has evolved, ``language'' can refer to (1)
a set of hyphenation patterns as preloaded into the format, (2) a
package option, (3) an |ldf| file, and (4) a name used in the document
to select a language or dialect. So, a package option refers to a
language in a generic way -- sometimes it is the actual language name
used to select it, sometimes it is a file name loading a language with
a different name, sometimes it is a file name loading several
languages. Please, read the documentation for specific languages for
further info.

Loading directly |sty| files in \LaTeX{} (ie,
|\usepackage|\marg{language}) is deprecated and you will get the
error:\footnote{In former versions the error read ``You have used an
old interface to call babel'', not very helpful.}
\begin{verbatim}
! Package babel Error: You are loading directly a language style.
(babel)                This syntax is deprecated and you must use
(babel)                \usepackage[language]{babel}.
\end{verbatim}

Another typical error when using \babel{} is the
following:\footnote{In former versions the error read ``You haven't
loaded the language LANG yet''.}
\begin{verbatim}
! Package babel Error: Unknown language `LANG'. Either you have misspelled
(babel)                its name, it has not been installed, or you requested
(babel)                it in a previous run. Fix its name, install it or just
(babel)                rerun the file, respectively
\end{verbatim}
The most frequent reason is, by far, the latest (for example, you
included |spanish|, but you realized this language is not used after
all, and therefore you removed it from the option list). In most cases,
the error vanishes when the document is typeset again, but in more
severe ones you will need to remove the |aux| file.

In Plain, load languages styles with |\input| and then use
|\begindocument| (the latter is defined by \babel):
\begin{verbatim}[morekeywords={[0]{\input,\begindocument}}]
\input estonian.sty
\begindocument
\end{verbatim}
Note not all languages provide a |sty| file and some of them are
not compatible with Plain.\footnote{Even in the \babel{} kernel there
were some macros not compatible with plain. Hopefully these issues will
be fixed soon.}

\subsection{Selecting languages}

This section describes the commands to be used in the document to
switch the language in multilingual document.

The main language is selected automatically when the |document|
environment begins. In the preamble it has \textit{not} been selected,
except hyphenation patterns and the name assigned to |\languagename|
(in particular, shorthands, captions and date are not activated). If
you need to define boxes and the like in the preamble, you might want
to use some of the following commands.

\Describe\selectlanguage{\marg{language}}
When a user wants to switch from one language to another he can
do so using the macro |\selectlanguage|. This macro takes the
language, defined previously by a language definition file, as
its argument. It calls several macros that should be defined in
the language definition files to activate the special definitions
for the language chosen. For ``historical reasons'', a macro name is
converted to a language name without the leading |\|; in other words,
the two following declarations are equivalent:
\begin{verbatim}
\selectlanguage{german}
\selectlanguage{\german}
\end{verbatim}
Using a macro instead of a ``real'' name is deprecated.

If used inside braces there might be some non-local changes, as this
would be  roughly equivalent to:
\begin{verbatim}
{\selectlanguage{<inner-language>} ...}\selectlanguage{<outer-language>}
\end{verbatim}
If you want a change which is really local, you must enclose this
code with an additional grouping level.

This command can be used as environment, too.

\Describe{\begin\menv{otherlanguage}}{\marg{language}\Eenv{otherlanguage}}

The environment \Lenv{otherlanguage} does basically the same as
|\selectlanguage|, except the language change is (mostly) local to
the environment. 

Actually, there might be some non-local changes, as this environment
is roughly equivalent to:
\begin{verbatim}
\begingroup
\selectlanguage{<inner-language>}
...
\endgroup
\selectlanguage{<outer-language>}
\end{verbatim}
If you want a change which is really local, you must enclose this
environment with an additional grouping, like braces |{}|.

Spaces after the environment are ignored.

\Describe\foreignlanguage{\marg{language}\marg{text}}
The command |\foreignlanguage| takes two arguments; the second
argument is a phrase to be typeset according to the rules of the
language named in its first argument. This command (1) only
switches the extra definitions and the hyphenation rules for the
language, \emph{not} the names and dates, (2) does not send
information about the language to auxiliary files (i.e., the
surrounding language is still in force), and (3) it works even if
the language has not been set as package option (but in such a
case it only sets the hyphenation patterns and a warning is shown).

\Describe{\begin\menv{otherlanguage*}}%
{\marg{language}\Eenv{otherlanguage*}}

Same as |\foreignlanguage| but as environment. Spaces after the
environment are \textit{not} ignored.

This environment (or in some cases |otherlanguage|) may be required for
intermixing left-to-right typesetting with right-to-left typesetting
in engines not supporting a change in the writing direction inside a
line.

\Describe{\begin\menv{hyphenrules}}{\marg{language}\Eenv{hyphenrules}}

The environment \Lenv{hyphenrules} can be used to select \emph{only}
the hyphenation rules to be used (it can be used as command,
too). This can for instance be used to select `nohyphenation',
provided that in \file{language.dat} the `language'
\textsf{nohyphenation} is defined by loading \file{zerohyph.tex}. It
deactivates language shorthands, too (but not user shorthands).

Except for these simple uses, |hyphenrules| is discouraged and
|otherlanguage*| (the starred version) is preferred, as the former
does not take into account possible changes in encodings or characters
like, say, |'| done by some languages (eg, \textsf{italian},
\textsf{frenchb}, \textsf{ukraineb}). To set hyphenation exceptions,
use |\babelhyphenation| (see below).

\subsection{More on selection}

\Describe\babeltags{\char`\{\m{tag1} \texttt{=} \m{language1}, \m{tag2}
\texttt{=} \m{language2}, \dots\char`\}} 

\New{3.9i} In multilingual documents with many language switches the commands
above can be cumbersome. With this tool shorter names can be
defined. It adds nothing really new -- it is just syntactical sugar.

It defines |\text|\m{tag1}\marg{text} to be
|\foreignlanguage|\marg{language1}\marg{text}, and |\begin|\marg{tag1}
  to be |\begin{otherlanguage*}|\marg{language1}, and so on. Note
    |\|\m{tag1} is also allowed, but remember set it locally inside a
    group. So, with
\begin{verbatim}
\babeltags{de = german}
\end{verbatim}
yo can write
\begin{verbatim}
text \textde{German text} text
\end{verbatim}
and
\begin{verbatim}
text
\begin{de}
German text
\end{de}
text
\end{verbatim}

\Describe\babelensure{|[include=|\m{commands}|,exclude=|\m{commands}%
  |,fontenc=|\m{encoding}|]|\marg{language}}

\New{3.9i} Except in a few languages, like Russian, captions and
dates are just strings, and do not switch the language. That means
you should set it explicitly if you want to use them, or hyphenation
(and in some cases the text itself) will be wrong. For example:
\begin{verbatim}
\foreignlanguage{russian}{text \foreignlanguage{polish}{\seename} text}
\end{verbatim}

Of course, \TeX{} can do it for you. To avoid switching the language
all the while, |\babelensure| redefines the captions for a given
language to wrap them with a selector. By default only the basic
captions and |\today| are redefined, but you can add further macros
with the key |include| in the optional argument (without
commas). Macros not to be modified are listed in |exclude|. You can
also enforce a font encoding with |fontenc|.\footnote{With it encoded
string may not work as expected.} A couple of examples:
\begin{verbatim}
\babelensure[include=\Today]{spanish}
\babelensure[fontenc=T5]{vietnamese}
\end{verbatim}

They are activated when the language is selected (at the |afterextras|
event), and it makes some assumptions which could not be fulfilled in
some languages. Note also you should include only macros defined by
the language, not global macros (eg, |\TeX| of |\dag|).

\subsection{Getting the current language name}

\Describe\languagename{}
The control sequence |\languagename| contains the name of the
current language. However, due to some internal inconsistencies in
catcodes it should \textit{not} be used to test its value (use
\textsf{iflang}, by Heiko Oberdiek).

\Describe\iflanguage{\marg{language}\marg{true}\marg{false}}

If more than one language is used, it might be necessary to know which
language is active at a specific time. This can be checked by a call
to |\iflanguage|, but note here ``language'' is used in the \TeX\
sense, as a set of hyphenation patterns, and \textit{not} as its
\textsf{babel} name. This macro takes three arguments.  The first
argument is the name of a language; the second and third arguments are
the actions to take if the result of the test is true or false
respectively. The advice about |\languagename| also applies here --
use \textsf{iflang} instead of |\iflanguage| if possible.

\subsection{Selecting scripts}

Currently \babel{} provides no standard interface to select 
scripts, because they are best selected with either |\fontencoding|
(low level) or a language name (high level). Even the Latin script may
require different encodings (ie, sets of glyphs) depending on the
language, and therefore such a switch would be in a sense
incomplete.\footnote{The so-called Unicode fonts does not improve the
situation either. So, a font suited for Vietnamese is not necessarily
suited for, say, romanization of Indic languages, and the fact it
contains glyphs for Modern Greek does not mean it includes them for
Classic Greek. As to directionality, it poses special challenges
because it also affects individual characters and layout elements.}

Some languages sharing the same script define macros to switch it (eg,
|\textcyrillic|), but be aware they may also set the language to a
certain default. Even the \babel{} core defined |\textlatin|, but is
was somewhat buggy because in some cases it messed up encodings and
fonts (for example, if the main latin encoding was |LY1|), and
therefore it has been deprecated.\footnote{But still defined for
backwards compatibility.}

\Describe{\ensureascii}{\marg{text}}

\New{3.9i} This macro makes sure \m{text} is typeset with a
LICR-savvy encoding in the ASCII range. It is used to redefine |\TeX|
and |\LaTeX| so that they are correctly typeset even with |LGR| or
|X2| (the complete list is stored in |\BabelNonASCII|, which by default
is |LGR|, |X2|, |OT2|, |OT3|, |OT6|, |LHE|, |LWN|, |LMA|, |LMC|,
|LMS|, |LMU|, but you can modify it). So, in some sense it fixes the
bug described in the previous paragraph.

If non-ASCII encodings are not loaded (or no encoding at all), it is
no-op (also |\TeX| and |\LaTeX| are not redefined); otherwise,
|\ensureascii| switches to the encoding at the beginning of the
document if ASCII-savvy, or else the last ASCII-savvy encoding
loaded. For example, if you load |LY1,LGR|, then it is set to |LY1|,
but if you load |LY1,T2A| it is set to |T2A|. The symbol encodings
|TS1|, |T3|, and |TS3| are not taken into account, since they are not
used for ``ordinary'' text.

The foregoing rules (which are applied ``at begin document'') cover
most of cases. Note no asumption is made on characters above
127, which may not follow the LICR conventions -- the goal is just
to ensure most of the ASCII letters and symbols are the right ones.

\subsection{Shorthands}

A \textit{shorthand} is a sequence of one or two characters that
expands to arbitrary \TeX{} code.

Shorthands can be used for different kinds of things, as for example:
(1) in some languages shorthands such as |"a| are defined to be able
to hyphenate the word if the encoding is |OT1|; (2) in some languages
shorthands such as |!| are used to insert the right amount of white
space; (3) several kinds of discretionaries and breaks can be inserted
easily with |"-|, |"=|, etc.

The package \textsf{inputenc} as well as \xetex{} an \luatex{} have
alleviated entering non-ASCII characters, but minority languages and
some kinds of text can still require characters not directly
available in the keyboards (and sometimes not even as separated or
precomposed Unicode characters). As to the point 2, now
\textsf{pdfTeX} provides |\knbccode|. Tools of point 3 can be still
very useful in general.

There are three levels of shorthands: \textit{user},
\textit{language}, and \textit{system} (by order of
precedence). Version 3.9 introduces the \textit{language user} level
on top of the user level, as described below. In most cases, you will
use only shorthands provided by languages.

Please, note the following:
\begin{enumerate}
\item Activated chars used for two-char shorthands cannot be followed
  by a closing brace |}| and the spaces following are gobbled.  With
  one-char shorthands (eg,~|:|), they are preserved.
\item If on a certain level (system, language, user) there is a
  one-char shorthand, two-char ones starting with that 
  char and on the same level are ignored.
\end{enumerate}

A typical error when using shorthands is the following:
\begin{verbatim}
! Argument of \language@active@arg" has an extra }.
\end{verbatim}
It means there is a closing brace just after a shorthand, which is not
allowed (eg,~|"}|). Just add |{}| after (eg,~|"{}}|). 

\Describe{\shorthandon}{\marg{shorthands-list}}
\DescribeOther{\shorthandoff}{%
\colorbox{thegrey}{\ttfamily\hskip-.2em*\hskip-.2em}%
\marg{shorthands-list}}
It is sometimes necessary to switch a shorthand
character off temporarily, because it must be used in an
entirely different way. For this purpose, the user commands
|\shorthandoff| and |\shorthandon| are provided. They each take a
list of characters as their arguments.

The command |\shorthandoff| sets the |\catcode| for each of the
characters in its argument to other (12); the command |\shorthandon|
sets the |\catcode| to active (13). Both commands only work on `known'
shorthand characters. If a character is not known to be a shorthand
character its category code will be left unchanged.

\New{3.9a} Note however, |\shorthandoff| does not behave as
you would expect with characters like |~| or |^|, because they
usually are not ``other''. For them |\shorthandoff*| is provided,
so that with
\begin{verbatim}
\shorthandoff*{~^}
\end{verbatim}
|~| is still active, very likely with the meaning of a non-breaking
space, and |^| is the superscript character. The catcodes used are
those when the shorthands are defined, usually when language files are
loaded.

\Describe{\useshorthands}{%
\colorbox{thegrey}{\ttfamily\hskip-.2em*\hskip-.2em}%
\marg{char}}

The command |\useshorthands| initiates the definition of user-defined
shorthand sequences. It has one argument, the character that starts
these personal shorthands.

\New{3.9a} However, user shorthands are not always alive, as they may
be deactivated by languages (for example, if you use |"| for your user
shorthands and switch from \textsf{german} to \textsf{french}, they
stop working). Therefore, a starred version
|\useshorthands*|\marg{char} is provided, which makes sure shorthands
are always activated.

Currently, if the package option |shorthands| is used, you must include any
character to be activated with |\useshorthands|. This restriction will
be lifted in a future release.

\Describe\defineshorthand{\texttt{[}\langlist\texttt{]}%^^A
     \marg{shorthand}\marg{code}}

The command |\defineshorthand| takes two arguments: the first is
a one- or two-character shorthand sequence, and the second is the
code the shorthand should expand to.

\New{3.9a} An optional argument allows to (re)define language
and system shorthands (some languages do not activate shorthands,
so you may want to add |\languageshorthands|\marg{lang} to the
corresponding |\extras|\m{lang}). By default, user shorthands are
(re)defined.

User shorthands override language ones, which in turn override
system shorthands. Language-dependent user shorthands (new in
3.9) take precedence over ``normal'' user shorthands.

As an example of their applications, let's assume you want a
unified set of shorthand for discretionaries (languages do not
define shorthands consistently, and |"-|, |\-|, |"=| have
different meanings).  You could start with, say:
\begin{verbatim}
\useshorthands*{"}
\defineshorthand{"*}{\babelhyphen{soft}}
\defineshorthand{"-}{\babelhyphen{hard}}
\end{verbatim}
However, behaviour of hyphens is language dependent. For example, in
languages like Polish and Portugese, a hard hyphen inside compound
words are repeated at the beginning of the next line. You could then
set:
\begin{verbatim}[morekeywords={[1]{polish,portugese}}]
\defineshorthand[*polish,*portugese]{"-}{\babelhyphen{repeat}}
\end{verbatim}
Here, options with |*| set a language-dependent user shorthand, which
means the generic one above only applies for the rest of languages;
without |*| they would (re)define the language shorthands instead,
which are overriden by user ones.

Now, you have a single unified shorthand (|"-|), with a content-based
meaning (`compound word hyphen') whose visual behavior is that
expected in each context.

\Describe\aliasshorthand{\marg{original}\marg{alias}}

The command |\aliasshorthand| can be used to let another
character perform the same functions as the default shorthand
character. If one prefers for example to use the character |/|
over |"| in typing Polish texts, this can be achieved by entering
|\aliasshorthand{"}{/}|. \emph{Please note} the substitute
character must \textit{not} have been declared before as
shorthand (in such case, |\aliashorthands| is ignored).

The following example shows how to replace a shorthand by another
\begin{verbatim}[morekeywords={[0]{\aliasshorthand}}]
\aliasshorthand{~}{^}
\AtBeginDocument{\shorthandoff*{~}}
\end{verbatim}
However, shorthands remember somehow the original character, and the
fallback value is that of the latter. So, in this example, if no
shorthand if found, |^| expands to a non-breaking space, because this
is the value of |~| (internally, |^| calls |\active@char~| or
|\normal@char~|). Furthermore, if you change the |system| value of |^|
with |\defineshorthand| nothing happens.

\Describe\languageshorthands{\marg{language}} The command
|\languageshorthands| can be used to switch the shorthands on the
language level. It takes one argument, the name of a language or
|none| (the latter does what its name suggests).\footnote{Actually,
any name not corresponding to a language group does the same as
\texttt{none}. However, follow this convention because it might be
enforced in future releases of \babel{} to catch possible errors.}
Note that for this to work the language should have been specified as
an option when loading the \babel\ package.  For example, you can use
in \textsf{english} the shorthands defined by \textsf{ngerman} with
\begin{verbatim}
\addto\extrasenglish{\languageshorthands{ngerman}}
\end{verbatim}

Very often, this is a more convenient way to deactivate shorthands
than |\shorthandoff|, as for example if you want to define a macro
to easy typing phonetic characters with \textsf{tipa}:
\begin{verbatim}
\newcommand{\myipa}[1]{{\languageshorthands{none}\tipaencoding#1}}
\end{verbatim}

\Describe\babelshorthand{\marg{shorthand}}
With this command you can use a shorthand even if (1) not activated in
\texttt{shorthands} (in this case only shorthands for the current
language are taken into account, ie, not user shorthands), (2) turned
off with |\shorthandoff| or (3) deactivated with the internal
|\bbl@deactivate|; for example, \verb|\babelshorthand{"u}| or
\verb|\babelshorthand{:}|.  (You can conveniently define your own
macros, or even you own user shorthands provided they do not ovelap.)

For your records, here is a list of shorthands, but you must check
them, as they may change:\footnote{Thanks to Enrico Gregorio}

\begin{description}
\itemsep=-\parskip
\item[Languages with no shorthands] Croatian, English (any variety),
  Indonesian, Hebrew, Interlingua, Irish, Lower Sorbian, Malaysian,
  North Sami, Romanian, Scottish, Welsh
\item[Languages with only \texttt{"} as defined shorthand character]
  Albanian, Bulgarian, Danish, Dutch, Finnish, German (old and new
  orthography, also Austrian), Icelandic, Italian, Norwegian, Polish,
  Portuguese (also Brazilian), Russian, Serbian (with Latin script),
  Slovene, Swedish, Ukrainian, Upper Sorbian
\item[Basque] |" ' ~|
\item[Breton] |: ; ? !|
\item[Catalan] |" ' `|
\item[Czech] |" -|
\item[Esperanto] |^|
\item[Estonian] |" ~|
\item[French] (all varieties) |: ; ? !|
\item[Galician] |" . ' ~ < >|
\item[Greek] |~|
\item[Hungarian] |`|
\item[Kurmanji] |^|
\item[Latin] |" ^ =|
\item[Slovak] |" ^ ' -|
\item[Spanish] |" . < > '|
\item[Turkish] |: ! =|
\end{description}
In addition, the \babel{} core declares |~| as a one-char shorthand
which is let, like the standard |~|, to a non breaking
space.\footnote{This declaration serves to nothing, but it is
preserved for backward compatibility.}


\subsection{Package options}

\New{3.9a}
These package options are processed before language options, so
that they are taken into account irrespective of its order. The first
three options have been available in previous versions.

\Describe{KeepShorthandsActive}{}
Tells babel not to deactivate shorthands after loading a language
file, so that they are also availabe in the preamble.

\Describe{activeacute}{} For some languages \babel\ supports this
options to set |'| as a shorthand in case it is not done by default.

\Describe{activegrave}{}
Same for |`|.

\Describe{shorthands=}{\meta{char}\meta{char}...
$\string|$ \texttt{off}}
The only language shorthands activated
are those given, like, eg:
\begin{verbatim}
\usepackage[esperanto,frenchb,shorthands=:;!?]{babel}
\end{verbatim} 
If \verb|'| is included, \texttt{activeacute} is set; if \verb|`| is
included, \texttt{activegrave} is set.  Active characters (like
\verb|~|) should be preceded by \verb|\string| (otherwise they will be
expanded by \LaTeX{} before they are passed to the package and
therefore they will not be recognized); however, |t| is provided for
the common case of |~| (as well as |c| for not so common case of the
comma).

With |shorthands=off| no language shorthands are defined,
As some languages use this mechanism for tools not available
otherwise, a macro \verb|\babelshorthand| is defined, which allows
using them; see above.

\Describe{safe=}{\texttt{none} $\string|$ \texttt{ref}
$\string|$ \texttt{bib}}
Some \LaTeX{} macros are redefined so that using
shorthands is safe. With \texttt{safe=bib} only |\nocite|, |\bibcite| and
|\bibitem| are  redefined. With |safe=ref| only |\newlabel|,  |\ref|
and |\pageref| are  redefined (as well as a few macros from
\textsf{varioref} and \textsf{ifthen}). With |safe=none| no macro is
redefined. Of course, in such a case you cannot use shorthands in
these macros.

\Describe{math=}{\texttt{active} $\string|$ \texttt{normal}}
Shorthands are mainly intended for text, not for math. By setting this
option with the value |normal| they are deactivated in math mode
(default is |active|) and things like |${a'}$| (a closing brace after
a shorthand) are not a source of trouble any more.

\Describe{config=}{\meta{file}} Load \meta{file}\texttt{.cfg} instead
of the default config file |bblopts.cfg|.

\Describe{main=}{\meta{language}} Sets the main language, as explained
above, ie, this language is always loaded last. If it is not given as
package or global option, it is added to the list of requested
languages.

\Describe{headfoot=}{\meta{language}} By default, headlines and
footlines are not touched (only marks), and if they contain language
dependent macros (which is not usual) there may be unexpected
results. With this option you may set the language in heads and foots.

\Describe{noconfigs}{} Global and language default config files are
not loaded, so you can make sure your document is not spoilt by an
unexpected \texttt{.cfg} file. However, if the key |config| is set,
this file is loaded.

\Describe{showlanguages}{} Prints to the log the list of languages
loaded when the format was created: number (remember dialects can
share it), name, hyphenation file and exceptions file. 

\Describe{nocase}{} \New{3.9l} Language settings for uppercase and
lowercase mapping (as set by |\SetCase|) is ignored. Use only if there
are incompatibilities with other packages.

\Describe{silent}{} \New{3.9l} No warnings and no \textit{infos} are
written to the log file.\footnote{You can use alternatively the
package \textsf{silence}.}

\Describe{strings=}{\texttt{generic} $\string|$ \texttt{unicode}
$\string|$ \texttt{encoded} $\string|$ \meta{label} $\string|$
\meta{font encoding}} Selects the encoding of strings in languages
supporting this feature. Predefined labels are |generic| (for
traditional \TeX, LICR and ASCII strings), |unicode| (for engines like
\xetex{} and \luatex) and |encoded| (for special cases requiring mixed
encodings). Other allowed values are font encoding codes (|T1|, |T2A|,
|LGR|, |L7X|...), but only in languages supporting them. Be aware with
|encoded| captions are protected, but they work in |\MakeUppercase|
and the like.

\Describe{hyphenmap=}{\texttt{off} $\string|$ \texttt{main}
$\string|$ \texttt{select} $\string|$ \texttt{other} $\string|$
\texttt{other*}}

\New{3.9g} Sets the behaviour of case mapping for hyphenation,
provided the language defines it.\footnote{Turned off in plain.} It
can take the following values:
\begin{description}
\renewcommand\makelabel[1]{%
  \hspace\labelsep\normalfont\ttfamily\color{thered}#1}
\itemsep=-\parskip
\item[off] deactivates this feature and no case mapping is applied;
\item[first] sets it at the first switching commands in the
  current or parent scope (typically, when the aux file is first read
  and at |\begin{document}|, but also the first |\selectlanguage| in
    the preamble), and it's the default if a single
    language option has been stated;\footnote{Duplicated options count
    as several ones.}
\item[select] sets it only at |\selectlanguage|;
\item[other] also sets it at |otherlanguage|;
\item[other*] also sets it at |otherlanguage*| as well as in heads and
  foots (if the option |headfoot| is used) and in auxiliary files (ie,
  at |\select@language|), and it's the default if several language
  options have been stated. The option |first| can be regarded as an
  optimized version of \texttt{other*} for monolingual
  documents.\footnote{Providing |foreign| is pointless, because the
  case mapping applied is that at the end of paragraph, but if either
  \xetex{} or \luatex{} change this behaviour it might be added. On
  the other hand, |other| is provided even if I [JBL] think it isn't
  really useful, but who knows.}
\end{description}

\subsection{The \texttt{base} option}

With this package option \babel{} just loads some basic macros (those
in |switch.def|), defines |\AfterBabelLanguage| and exits. It also
selects the hyphenations patterns for the last language passed as
option (by its name in |language.dat|). There are two main uses:
classes and packages, and as a last resort in case there are, for some
reason, incompatible languages. It can be used if you just want to
select the hyphenations patterns of a single language, too.

\Describe\AfterBabelLanguage{\marg{option-name}\marg{code}}

This command is currently the only provided by |base|. Executes
\meta{code} when the file loaded by the corresponding package option
is finished (at |\ldf@finish|). The setting is global. So
\begin{verbatim}
\AfterBabelLanguage{frenchb}{...}
\end{verbatim}
does ... at the end of |frenchb.ldf|. It can be used in |ldf| files,
too, but in such a case the code is executed only if
\meta{option-name} is the same as |\CurrentOption| (which could not
be the same as the option name as set in |\usepackage|!). 

For example, consider two languages \textsf{foo} and \textsf{bar}
defining the same |\macro| with |\newcommand|. An error is raised if
you attempt to load both. Here is a way to overcome this problem:
\begin{verbatim}
\usepackage[base]{babel}
\AfterBabelLanguage{foo}{%
  \let\macroFoo\macro
  \let\macro\relax}
\usepackage[foo,bar]{babel}
\end{verbatim}

\subsection{Hooks}

\New{3.9a} A hook is a piece of code to be executed at certain
events. Some hooks are predefined when \luatex{} and \xetex{} are
used.

\Describe\AddBabelHook{\marg{name}\marg{event}\marg{code}}

The same name can be applied to several events.  Hooks may be enabled
and disabled for all defined events with
|\EnableBabelHook|\marg{name}, |\DisableBabelHook|\marg{name}. Names
containing the string |babel| are reserved (they are used, for
example, by |\useshortands*| to add a hook for the event
|afterextras|).

Current events are the following; in some of them you can use one to
three \TeX{} parameters (|#1|, |#2|, |#3|), with the meaning given:
\begin{description}
\renewcommand\makelabel[1]{%
  \hspace\labelsep\normalfont\ttfamily\color{thered}#1}
\itemsep=-\parskip
\item[adddialect] (language name, dialect name) Used by
  \file{luababel.def} to load the patterns if not preloaded.
\item[patterns] (language name, language with encoding) Executed just
  after the |\language| has been set. The second argument has the
  patterns name actually selected (in the form of either |lang:ENC| or
  |lang|).
\item[hyphenation] (language name, language with encoding) Executed
  locally just before exceptions given in |\babelhyphenation| are
  actually set.
\item[defaultcommands] Used (locally) in |\StartBabelCommands|.
\item[encodedcommands] (input, font encodings) Used (locally) in
  |\StartBabelCommands|. Both \xetex{} and \luatex{} make sure the
  encoded text is read correctly.
\item[stopcommands] Used to reset the the above, if necessary.
\item[write] This event comes just after the switching commands are
  written to the |aux| file.
\item[beforeextras] Just before executing |\extras|\m{language}. This
  event and the next one should not contain language-dependent code
  (for that, add it to |\extras|\m{language}).
\item[afterextras] Just after executing |\extras|\m{language}. For
  example, the following deactivates shorthands in all languages:
\begin{verbatim}
\AddBabelHook{noshort}{afterextras}{\languageshorthands{none}}
\end{verbatim}
\item[stringprocess] Instead of a parameter, you can manipulate the
  macro |\BabelString| containing the string to be defined with
  |\SetString|. For example, to use an expanded version of the string
  in the definition, write:
\begin{verbatim}
\AddBabelHook{myhook}{stringprocess}{%
  \protected@edef\BabelString{\BabelString}}
\end{verbatim}
\item[initiateactive] (char as active, char as other, original char)
  \New{3.9i} Executed just after a shorthand has been `initiated'. The three
  parameters are the same character with different catcodes: active,
  other (|\string|'ed) and the original one.
\item[afterreset] \New{3.9i} Executed when selecting a language just after
  |\originalTeX| is run and reset to its base value, before executing
  |\captions|\m{language} and |\date|\m{language}.
\end{description}

Four events are used in \file{hyphen.cfg}, which are handled in a
quite different way for efficiency reasons -- unlike the precedent
ones, they only have a single hook and replace a default definition. 
\begin{description}
\renewcommand\makelabel[1]{%
  \hspace\labelsep\normalfont\ttfamily\color{thered}#1}
\itemsep=-\parskip
\item[everylanguage] (language) Executed before every language patterns are loaded.
\item[loadkernel] (file) By default loads |switch.def|. It can be used
  to load a different version of this files or to load nothing.
\item[loadpatterns] (patterns file) Loads the patterns file. Used by
  \file{luababel.def}.
\item[loadexceptions] (exceptions file) Loads the exceptions
  file. Used by \file{luababel.def}.
\end{description}

\Describe\BabelContentsFiles{}
\New{3.9a} This macro contains a list of ``toc'' types which
require a command to switch the language. Its default value is
|toc,lof,lot|, but you may redefine it with |\renewcommand| (it's up
to you to make sure no toc type is duplicated).

\subsection{Hyphenation tools}

\Describe\babelhyphen{%
  \colorbox{thegrey}{\ttfamily\hskip-.2em*\hskip-.2em}\marg{type}}
\DescribeOther\babelhyphen{%
  \colorbox{thegrey}{\ttfamily\hskip-.2em*\hskip-.2em}\marg{text}}

\New{3.9a} It is customary to classify hyphens in two types: (1)
\textit{explicit} or \textit{hard hyphens}, which in \TeX\ are
entered as \verb|-|, and (2) \textit{optional} or \textit{soft
hyphens}, which are entered as \verb|\-|. Strictly, a \textit{soft
hyphen} is not a hyphen, but just a breaking oportunity or, in
\TeX\ terms, a ``discretionary''; a \textit{hard hyphen} is a hyphen
with a breaking oportunity after it. A further type is a
\textit{non-breaking hyphen}, a hyphen without a breaking
oportunity.

In \TeX, \verb|-| and \verb|\-| forbid further breaking oportunities
in the word. This is the desired behaviour very often, but not
always, and therefore many languages provide shorthands for these
cases. Unfortunately, this has not been done consistently: for
example, in Dutch, Portugese, Catalan or Danish, \verb|"-| is a hard
hyphen, while in German, Spanish, Norwegian, Slovak or Russian, it
is a soft hyphen. Furthermore, some of them even redefine |\-|, so
that you cannot insert a soft hyphen without breaking oportunities
in the rest of the word.

Therefore, some macros are provide with a set of basic ``hyphens''
which can be used by themselves, to define a user shorthand, or even
in language files.
\begin{itemize}
\item |\babelhyphen{soft}| and |\babelhyphen{hard}| are self
  explanatory.
\item |\babelhyphen{repeat}| inserts a hard hyphen which is repeated
  at the beginning of the next line, as done in languages like
  Polish, Portugese and Spanish.
\item |\babelhyphen{nobreak}| inserts a hard hyphen without a break
  after it (even if a space follows).
\item |\babelhyphen{empty}| inserts a break oportunity without
  a hyphen at all.
\item |\babelhyphen|\marg{text} is a hard ``hyphen'' using \m{text}
  instead. A typical case is |\babelhyphen{/}|.
\end{itemize}
With all of them hyphenation in the rest of the word is enabled. If
you don't want enabling it, there is a starred counterpart:
|\babelhyphen*{soft}| (which in most cases is equivalent to the
original |\-|), |\babelhyphen*{hard}|, etc.

Note |hard| is also good for isolated prefixes (eg, \textit{anti-})
and |nobreak| for isolated suffixes (eg, \textit{-ism}), but in both
cases |\babelhyphen*{nobreak}| is usually better. 

There are also some differences with \LaTeX: (1) the character used is
that set for the current font, while in \LaTeX{} it is hardwired to
|-| (a typical value); (2) the hyphen to be used in fonts with a
negative |\hyphenchar| is  |-|, like in \LaTeX, but it can be changed to
another value by redefining |\babelnullhyphen|; (3) a break after the
hyphen is forbidden if preceded by a glue ${>}0$~pt (at the beginning
of a word, provided it is not immediately preceded by, say, a
parenthesis).

\Describe\babelhyphenation{\texttt{[}\langlist\texttt{]}%^^A
    \marg{exceptions}}

\New{3.9a} Sets hyphenation exceptions for the languages given
or, without the optional argument, for \textit{all} languages (eg,
proper nouns or common loan words, and of course monolingual
documents). Language exceptions take precedence over global ones.

It can be used only in the preamble, and exceptions are set when the
language is first selected, thus taking into account changes of
|\lccodes|'s done in |\extras|\m{lang} as well as the language specific
encoding (not set in the preamble by default). Multiple
|\babelhyphenation|'s are allowed. For example:
\begin{verbatim}
\babelhyphenation{Wal-hal-la Dar-bhan-ga}
\end{verbatim}

Listed words are saved expanded and therefore it relies on the
LICR. Of course, it also works without the LICR if the input and the
font encodings are the same, like in Unicode based engines.

\subsection{Language attributes}

\DescribeMacro{\languageattribute}
This is a user-level command, to be used in the preamble of a
document (after |\usepackage[...]{babel}|), that declares which
attributes are to be used for a given language. It takes two
arguments: the first is the name of the language; the second,
a (list of) attribute(s) to be used. Attributes must be set in the
preamble and only once -- they cannot be turned on and off.
The command checks whether the language is known in this document
and whether the attribute(s) are known for this language.

Very often, using a \textit{modifier} in a package option is better.

Several language definition files use their own methods to set
options. For example, \textsf{frenchb} uses |\frenchbsetup|,
\textsf{magyar} (1.5) uses |\magyarOptions|; modifiers provided by
|spanish| have no attribute counterparts. Macros settting
options are also used (eg, |\ProsodicMarksOn| in \textsf{latin}).

\subsection{Languages supported by \babel}

In the following table most of the languages supported by \babel\ are
listed, together with the names of the options  which you can load
\babel\ with for each language. Note this list is open and the
current options may be different. 

\begin{description}
\itemsep=-\parskip
\sffamily
\item[Afrikaans] afrikaans
\item[Bahasa] bahasa, indonesian, indon, bahasai,
    bahasam, malay, meyalu
\item[Basque] basque
\item[Breton] breton
\item[Bulgarian] bulgarian
\item[Catalan] catalan
\item[Croatian] croatian
\item[Czech] czech
\item[Danish] danish
\item[Dutch] dutch
\item[English] english, USenglish, american, UKenglish,
     british, canadian, australian, newzealand
\item[Esperanto] esperanto
\item[Estonian] estonian
\item[Finnish] finnish
\item[French] french, francais, canadien, acadian
\item[Galician] galician
\item[German] austrian, german, germanb, ngerman, naustrian
\item[Greek] greek, polutonikogreek
\item[Hebrew] hebrew
\item[Icelandic] icelandic
\item[Interlingua] interlingua
\item[Irish Gaelic] irish
\item[Italian] italian
\item[Latin] latin
\item[Lower Sorbian] lowersorbian
\item[North Sami] samin
\item[Norwegian] norsk, nynorsk
\item[Polish] polish
\item[Portuguese] portuges, portuguese, brazilian, brazil
\item[Romanian] romanian 
\item[Russian] russian
\item[Scottish Gaelic] scottish
\item[Spanish]  spanish
\item[Slovakian] slovak
\item[Slovenian]  slovene
\item[Swedish] swedish
\item[Serbian] serbian
\item[Turkish] turkish
\item[Ukrainian] ukrainian
\item[Upper Sorbian] uppersorbian
\item[Welsh] welsh
\end{description}

There are more languages not listed above, including \textsf{hindi,
thai, thaicjk, latvian, turkmen, magyar, mongolian, romansh,
lithuanian, spanglish, vietnamese, japanese, pinyin, arabic, farsi,
ibygreek, bgreek, serbianc, frenchle, ethiop} and \textsf{friulan}.

Most of them work out of the box, but some may require extra fonts,
encoding files, a preprocessor or even a complete framework (like
CJK).  For example, if you have got the \textsf{velthuis/devnag} package,
you can create a file with extension |.dn|:
\begin{verbatim}
\documentclass{article}
\usepackage[hindi]{babel}
\begin{document}
{\dn devaanaa.m priya.h}
\end{document}
\end{verbatim}
Then you preprocess it with |devnag| \m{file}, which creates
\m{file}|.tex|; you can then typeset the latter with \LaTeX.

\subsection{Tips, workarounds, know issues and notes}

\begin{itemize}
\item If you use the document class \cls{book} \emph{and} you use
  |\ref| inside the argument of |\chapter| (or just use |\ref| inside
  |\MakeUppercase|), \LaTeX\ will keep complaining about an undefined
  label.  To prevent such problems, you could revert to using
  uppercase labels, you can use |\lowercase{\ref{foo}}| inside the
  argument of |\chapter|, or, if you will not use shorthands in
  labels, set the |safe| option to |none| or |bib|.

\item\catcode`\|=12\relax Both \textsf{ltxdoc} and \textsf{babel} use
  \verb|\AtBeginDocument| to change some catcodes, and babel reloads
  \textsf{hhline} to make sure \verb|:| has the right one, so if you
  want to change the catcode of \verb/|/ it has to be done using the
  same method at the proper place, with
\begin{verbatim}
\AtBeginDocument{\DeleteShortVerb{\|}}
\end{verbatim}
  \textit{before} loading babel. This way, when the document begins
  the sequence is (1) make \verb/|/ active (\textsf{ltxdoc}); (2) make
  it unactive (your settings); (3) make babel shorthands active
  (\textsf{babel)}; (4) reload \textsf{hhline} (\textsf{babel}, now
  with the correct catcodes for \verb/|/ and
  \verb|:|).\catcode`\|=\active

\item Documents with several input encodings are not frequent, but
  sometimes are useful. You can set different encodings for different
  languages as the following example shows:
\begin{verbatim}
\addto\extrasfrench{\inputencoding{latin1}}
\addto\extrasrussian{\inputencoding{koi8-r}}
\end{verbatim}
   (A recent version of \textsf{inputenc} is required.)
 \item For the hyphenation to work correctly, lccodes cannot change,
   because \TeX{} only takes into account the values when the
   paragraph is hyphenated, i.e., when it has been
   finished.\footnote{This explains why \LaTeX{} assumes the lowercase
   mapping of T1 and does not provide a tool for multiple
   mappings. Unfortunately, \cs{savinghyphcodes} is not a solution
   either, because lccodes for hyphenation are frozen in the format
   and cannot be changed.} So, if you write a chunk of French text
   with |\foreinglanguage|, the apostrophes might not be taken into
   account. This is a limitation of \TeX, not of
   \babel. Alternatively, you may use |\useshorthands| to activate |'|
   and |\defineshorthand|, or redefine |\textquoteright| (the latter
   is called by the non-ASCII right quote).
\item \verb|\bibitem| is out of sync with \verb|\selectlanguage| in
  the \file{.aux} file. The reason is \verb|\bibitem| uses
  \verb|\immediate| (and others, in fact), while
  \verb|\selectlanguage| doesn't. There is no known workaround.
\item Babel does not take into account |\normalsfcodes| and
  (non-)French spacing is not always properly (un)set by
  languages. However, problems are unlikely to happen and therefore
  this part remains untouched in version 3.9 (but it is in the `to
  do' list). 
\item Using a character mathematically active (ie, with math code
  |"8000|) as a shorthand can make \TeX{} enter in an infinite
  loop. (Another issue in the `to do' list, although there is a
  partial solution.)
\item Plain \luatex{} does not load patterns on the fly. Since this
format is not based on \babel{} but on \file{etex.src} further
investigation is required. This is another task in the `to do' list.
\end{itemize}

The following packages can be useful, too (the list is still
far from complete):
\begin{description}
\itemsep=-\parskip
\item[csquotes] Logical markup for quotes.
\item[iflang] Tests correctly the current language.
\item[hyphsubst] Selects a different set of patterns for a language.
\item[translator] An open platform for packages that need to be
  localized.
\item[siunitx] Typesetting of numbers and physical quantities.
\item[biblatex] Programmable bibliographies and citations.
\item[bicaption] Bilingual captions.
\item[babelbib] Multilingual bibliographies.
\item[microtype] Adjusts the typesetting according to
some languages (kerning and spacing). Ligatures can be disabled.
\item[substitutefont] Combines fonts in several encodings.
\item[mkpattern] Generates hyphenation patterns.
\end{description}

\subsection{Future work}

Useful additions would be, for example, time, currency, addresses and
personal names.\footnote{See for example POSIX, ISO 14652 and the
Unicode Common Locale Data Repository (CLDR).}. But that is the easy
part, because they don't require modifying the \LaTeX{} internals.

More interesting are differences in the sentence structure or related to
it. For example, in Basque the number precedes the name (including
chapters), in Hungarian ``from (1)'' is ``(1)-b\H{o}l'', but ``from (3)''
is ``(3)-b\'{o}l'', in Spanish an item labelled
``3.$^{\textrm{\scriptsize o}}$'' may
be referred to as either ``\'{\i}tem 3.$^{\textrm{\scriptsize o}}$'' or ``3.$^{\textrm{\scriptsize er}}$ \'{\i}tem'', and so on.

Even more interesting is right-to-left, vertical and bidi
typesetting. Babel provided a basic support for bidi text as part of
the style for Hebrew, but it is somewhat unsatisfactory and internally
replaces some hardwired commands by other hardwired commands
(generic changes would be much better).

Handling of ``Unicode'' fonts is also problematic. There is
\textsf{fontspec}, but special macros are required (not only the NFSS
ones) and it doesn't provide ``orthogonal axis'' for features,
including those related to the language (mainly language and
script). A couple of tentative macros, which solve the two main cases,
are provided by \babel{} ($\ge$3.9g) with a partial solution (only
\xetex{} and \luatex, for obvious reasons), but use them at your own
risk, as they might be removed in the future. For this very reason,
they are described here:
\begin{itemize}
\item |\babelFSstore|\marg{babel-language} sets the current three
  basic families (rm, sf, tt) as the default for the language
  given. In most cases, this macro will be enough.
\item |\babelFSdefault|\marg{babel-language}\marg{fontspec-features}
  patches |\fontspec| so that the given features are always passed as
  the optional argument or added to it (not an ideal solution). Use it
  only if you select some fonts in the document with |\fontspec|.
\end{itemize}
So, for example:
\begin{verbatim}
\setmainfont[Language=Turkish]{Minion Pro}
\setsansfont[Language=Turkish]{Myriad Pro}
\babelFSstore{turkish}
\setmainfont{Minion Pro}
\setsansfont{Myriad Pro}
\babelFSfeatures{turkish}{Language=Turkish}
\end{verbatim}
Note you can set any feature required for the language -- not only
|Language|, but also |Script| or a local |.fea|. This makes those macros
a bit more verbose, but also more powerful.

\section{Preloading languages with \file{language.dat}}

\TeX{} and most engines based on it (pdf\TeX, \xetex, $\epsilon$-\TeX,
the main exception being \luatex) require hyphenation patterns to be
loaded when a format is created (eg, \LaTeX, Xe\LaTeX,
pdf\LaTeX). \babel{} provides a tool which has become standand in many
distributions and based on a ``configuration file'' named
\file{language.dat}. The exact way this file is used depends on the
distribution, so please, read the documentation for the latter (note
also some distributions generate the file with some tool).

In that file the person who maintains a \TeX\ environment has to record
for which languages he has hyphenation patterns \emph{and} in which
files these are stored\footnote{This is because different operating
systems sometimes use \emph{very} different file-naming
conventions.}. When hyphenation exceptions are stored in a separate
file this can be indicated by naming that file \emph{after} the file
with the hyphenation patterns.

The file can contain empty lines and comments, as well as lines which
start with an equals (\texttt{=}) sign. Such a line will instruct
\LaTeX\ that the hyphenation patterns just processed have to be known
under an alternative name. Here is an example:
\begin{verbatim}
% File    : language.dat
% Purpose : tell iniTeX what files with patterns to load.
english    english.hyphenations
=british

dutch      hyphen.dutch exceptions.dutch % Nederlands
german hyphen.ger
\end{verbatim}

You may also set the font encoding the patterns are intended for by
following the language name by a colon and the encoding
code.\footnote{This in not a new feature, but in former versions it
didn't work correctly.} For example:
\begin{verbatim}
german:T1 hyphenT1.ger
german hyphen.ger
\end{verbatim}
With the previous settings, if the enconding when the language is
selected is |T1| then the patterns in \file{hyphenT1.ger} are
used, but otherwise use those in \file{hyphen.ger} (note the encoding
could be set in |\extras|\m{lang}).

A typical error when using \babel{} is the following:
\begin{verbatim}
No hyphenation patterns were preloaded for
the language `<lang>' into the format.
Please, configure your TeX system to add them and
rebuild the format. Now I will use the patterns
preloaded for english instead}}
\end{verbatim}
It simply means you must reconfigure \file{language.dat}, either by 
hand or with the tools provided by your distribution.

\section{The interface between the core of \babel{} and the language
definition files}

The \textit{language definition files} (ldf) must conform to a
number of conventions, because these files have to fill in the gaps
left by the common code in \file{babel.def}, i.\,e., the
definitions of the macros that produce texts.  Also the
language-switching possibility which has been built into the
\babel{} system has its implications.

The following assumptions are made:
\begin{itemize}
\item Some of the language-specific definitions might be used by plain
  \TeX\ users, so the files have to be coded so that they can be read
  by both \LaTeX\ and plain \TeX. The current format can be checked by
  looking at the value of the macro |\fmtname|.
\item The common part of the \babel{} system redefines a number of
  macros and environments (defined previously in the document style)
  to put in the names of macros that replace the previously hard-wired
  texts.  These macros have to be defined in the language definition
  files.
\item The language definition files must define five macros, used to
  activate and deactivate the language-specific definitions.  These
  macros are |\|\langvar|hyphenmins|, |\captions|\langvar,
  |\date|\langvar, |\extras|\langvar\ and |\noextras|\langvar (the
  last two may be left empty); where \langvar\ is either the name of
  the language definition file or the name of the \LaTeX\ option that
  is to be used. These macros and their functions are discussed
  below. You must define all or none for a language (or a dialect);
  defining, say, |\date|\langvar\ but not |\captions|\langvar\ does
  not raise an error but can lead to unexpected results.
\item When a language definition file is loaded, it can define
  |\l@|\langvar\ to be a dialect of |\language0| when |\l@|\langvar\
  is undefined.
\item Language names must be all lowercase. If an unknow language is
  selected, \babel{} will attempt setting it after lowercasing its
  name.
\item The semantics of modifiers is not defined (on purpose). In
  most cases, they will just be simple separated options (eg.,
  \texttt{spanish}), but a language might require, say, a set of
  options organized as a tree with suboptions (in such a case, the
  recommended separator is \verb|/|).
\end{itemize}

Some recommendations:
\begin{itemize}
\item The preferred shorthand is |"|, which is not used in \LaTeX{}
  (quotes are entered as |``| and |''|). Other good choices are
  characters which are not used in a certain context (eg, |=| in an
  ancient language). Note however |=|, |<|, |>|, |:| and the like
  can be dangerous, because they may be used as part of the syntax
  of some elements (numeric expressions, key/value pairs, etc.).
\item Captions should not contain shorthands or encoding dependent
  commands (the latter is not always possible, but should be clearly
  documented). They should be defined using the LICR. You may
  also use the new tools for encoded strings, described below.
\item Avoid adding things to |\noextras|\m{lang} except for umlauthigh
  and friends, |\bbl@deactivate|, |\bbl@(non)frenchspacing|, and
  language specific macros. Use always, if possible, |\bbl@save| and
  |\bbl@savevariable| (except if you still want to have access to the
  previous value). Do not reset a macro or a setting to a hardcoded
  value. Never. Instead save its value in |\extras|\m{lang}.
\item Do not switch scripts. If you want to make sure a set of glyphs
  is used, switch either the font encoding (low level) or the language
  (high level, which in turn may switch the font encoding). Usage of things
  like |\latintext| is deprecated.\footnote{But not removed, for backward
  compatibility.}
\end{itemize}

There are no special requirements for documenting your language
files. Now they are not included in the base \babel{} manual, so
provide a standalone document suited for your needs (and the
corresponding PDF, if you like), as well as other files you think can
be useful (eg, samples, readme).

\subsection{Basic macros}

In the core of the \babel{} system, several macros are defined for use
in language definition files. Their purpose is to make a new language
known. The first two are related to hyphenation patterns.

\DescribeMacro{\addlanguage}
The macro |\addlanguage| is a non-outer version of the macro
|\newlanguage|, defined in \file{plain.tex} version~3.x. For older
versions of \file{plain.tex} and \file{lplain.tex} a substitute
definition is used. Here ``language'' is used in the \TeX{} sense of
set of hyphenation patterns.

\DescribeMacro{\adddialect}
The macro |\adddialect| can be used when two languages can (or
must) use the same hyphenation patterns. This can also be useful
for languages for which no patterns are preloaded in the
format. In such cases the default behaviour of the \babel{}
system is to define this language as a `dialect' of the language
for which the patterns were loaded as |\language0|.  Here
``language'' is used in the \TeX{} sense of set of hyphenation
patterns.

\DescribeMacro{\<lang>hyphenmins}
The macro |\|\langvar|hyphenmins| is used to store the values of
the |\lefthyphenmin| and |\righthyphenmin|. Redefine this macro
to set your own values, with two numbers corresponding to these
two parameters. For example:
\begin{verbatim}
\renewcommand\spanishhyphenmins{34}
\end{verbatim}
(Assigning |\lefthyphenmin| and |\righthyphenmin| directly in
|\extras<lang>| has no effect.)

\DescribeMacro{\providehyphenmins}
The macro |\providehyphenmins| should be used in the language
definition files to set |\lefthyphenmin| and
|\righthyphenmin|. This macro will check whether these parameters
were provided by the hyphenation file before it takes any action.
If these values have been already set, this command is ignored
(currenty, default pattern files do \textit{not} set them).

\DescribeMacro{\captions\langvar}
The macro |\captions|\langvar\ defines the macros that
hold the texts to replace the original hard-wired texts.

\DescribeMacro{\date\langvar}
The macro |\date|\langvar\ defines |\today|.

\DescribeMacro{\extras\langvar}
The macro |\extras|\langvar\ contains all the extra definitions needed
for a specific language. This macro, like the following, is a hook --
you can add things to it, but it must not be used directly.

\DescribeMacro{\noextras\langvar}
Because we want to let the user switch
between languages, but we do not know what state \TeX\ might be in
after the execution of |\extras|\langvar, a macro that brings
\TeX\ into a predefined state is needed. It will be no surprise
that the name of this macro is |\noextras|\langvar.

\DescribeMacro{\bbl@declare@ttribute}
This is a command to be used in the language definition files for
declaring a language attribute. It takes three arguments: the
name of the language, the attribute to be defined, and the code
to be executed when the attribute is to be used.

\DescribeMacro{\main@language}
To postpone the activation of the definitions needed for a
language until the beginning of a document, all language
definition files should use |\main@language| instead of
|\selectlanguage|. This will just store the name of the language,
and the proper language will be activated at the start of the
document.

\DescribeMacro{\ProvidesLanguage}
The macro |\ProvidesLanguage| should be used to identify the
language definition files. Its syntax is similar to the syntax
of the \LaTeX\ command |\ProvidesPackage|.

\DescribeMacro{\LdfInit}
The macro |\LdfInit| performs a couple of standard checks that
must be made at the beginning of a language definition file,
such as checking the category code of the @-sign, preventing
the \file{.ldf} file from being processed twice, etc.

\DescribeMacro{\ldf@quit}
The macro |\ldf@quit| does work needed
if a \file{.ldf} file was processed
earlier. This includes resetting the category code
of the @-sign, preparing the language to be activated at
|\begin{document}| time, and ending the input stream.

\DescribeMacro{\ldf@finish}
The macro |\ldf@finish| does work needed
at the end of each \file{.ldf} file. This
includes resetting the category code of the @-sign,
loading a local configuration file, and preparing the language
to be activated at |\begin{document}| time.

\DescribeMacro{\loadlocalcfg}
After processing a language definition file,
\LaTeX\ can be instructed to load a local configuration
file. This file can, for instance, be used to add strings to
|\captions|\langvar\ to support local document
classes. The user will be informed that this
configuration file has been loaded. This macro is called by
|\ldf@finish|.

\DescribeMacro{\substitutefontfamily}
(Deprecated.) This command takes three arguments, a font encoding and
two font family names. It creates a font description file for the
first font in the given encoding. This \file{.fd} file will instruct
\LaTeX\ to use a font from the second family when a font from the
first family in the given encoding seems to be needed.

\subsection{Skeleton}

Here is the basic structure of an |ldf| file, with a language, a
dialect and an attribute. Strings are best defined using the method
explained in in sec. \ref{s:strings} (\babel{} 3.9 and later). 

\begin{verbatim}
\ProvidesLanguage{<language>}
     [2014/09/25 v0.0 <Language> support from the babel system]
\LdfInit{<language>}{captions<language>}

\ifx\undefined\l@<language>
  \@nopatterns{<Language>}
  \adddialect\l@<language>0
\fi

\adddialect\l@<dialect>\l@<language>

\bbl@declare@ttribute{<language>}{<attrib>}{%
  \expandafter\addto\expandafter\extras<language>
  \expandafter{\extras<attrib><language>}%
  \let\captions<language>\captions<attrib><language>}

\providehyphenmins{<language>}{\tw@\thr@@}

\StartBabelCommands*{<language>}{captions}
\SetString\chaptername{<chapter name>}
% More strings

\StartBabelCommands*{<language>}{date}
\SetString\monthiname{<name of first month>}
% More strings

\StartBabelCommands*{<dialect>}{captions}
\SetString\chaptername{<chapter name>}
% More strings

\StartBabelCommands*{<dialect>}{date}
\SetString\monthiname{<name of first month>}
% More strings

\EndBabelCommands

\addto\extras<language>{}
\addto\noextras<language>{}
\let\extras<dialect>\extras<language>
\let\noextras<dialect>\noextras<language>

\ldf@finish{<language>}
\end{verbatim}

\subsection{Support for active characters}

In quite a number of language definition files, active characters are
introduced. To facilitate this, some support macros are provided.

\DescribeMacro{\initiate@active@char}
The internal macro |\initiate@active@char| is used in language
definition files to instruct \LaTeX\ to give a character the category
code `active'. When a character has been made active it will remain
that way until the end of the document. Its definition may vary.

\DescribeMacro{\bbl@activate}
\DescribeMacro{\bbl@deactivate}
The command |\bbl@activate| is used to change the way an active
character expands. |\bbl@activate| `switches on' the active behaviour
of the character. |\bbl@deactivate| lets the active character expand
to its former (mostly) non-active self.

\DescribeMacro{\declare@shorthand}
The macro |\declare@shorthand| is used to define the various
shorthands. It takes three arguments: the name for the collection of
shorthands this definition belongs to; the character (sequence) that
makes up the shorthand, i.e.\ |~| or |"a|; and the code to be executed
when the shorthand is encountered. (It does \textit{not} raise an
error if the shorthand character has not been ``initiated''.)

\DescribeMacro{\bbl@add@special}
\DescribeMacro{\bbl@remove@special}
The \TeX book states: ``Plain \TeX\ includes a macro called
|\dospecials| that is essentially a set macro, representing the set of
all characters that have a special category code.'' \cite[p.~380]{DEK}
It is used to set text `verbatim'.  To make this work if more
characters get a special category code, you have to add this character
to the macro |\dospecial|.  \LaTeX\ adds another macro called
|\@sanitize| representing the same character set, but without the
curly braces.  The macros |\bbl@add@special|\meta{char} and
|\bbl@remove@special|\meta{char} add and remove the character
\meta{char} to these two sets.

\subsection{Support for saving macro definitions}

Language definition files may want to \emph{re}define macros that
already exist. Therefore a mechanism for saving (and restoring) the
original definition of those macros is provided. We provide two macros
for this\footnote{This mechanism was introduced by Bernd Raichle.}.

\DescribeMacro{\babel@save}
To save the current meaning of any control sequence, the macro
|\babel@save| is provided. It takes one argument, \meta{csname}, the
control sequence for which the meaning has to be saved.

\DescribeMacro{\babel@savevariable}
A second macro is provided to save the current value of a variable.
In this context, anything that is allowed after the |\the| primitive
is considered to be a variable. The macro takes one argument, the
\meta{variable}.

The effect of the preceding macros is to append a piece of code to
the current definition of |\originalTeX|. When |\originalTeX| is
expanded, this code restores the previous definition of the control
sequence or the previous value of the variable.

\subsection{Support for extending macros}

\DescribeMacro{\addto}
The macro |\addto{|\meta{control sequence}|}{|\meta{\TeX\ code}|}| can
be used to extend the definition of a macro. The macro need not be
defined (ie, it can be undefined or |\relax|). This macro can, for
instance, be used in adding instructions to a macro like
|\extrasenglish|.

Be careful when using this macro, because depending on the case the
assignment could be either global (usually) or local (sometimes). That
does not seems very consistent, but this behaviour is preserved for
backward compatibility. If you are using \pkg{etoolbox}, by Philipp
Lehman, consider using the tools provided by this package instead of
|\addto|.

\subsection{Macros common to a number of languages}

\DescribeMacro{\bbl@allowhyphens}
In several languages compound words are used. This means that when
\TeX\ has to hyphenate such a compound word, it only does so at the
`\texttt{-}' that is used in such words. To allow hyphenation in the
rest of such a compound word, the macro |\bbl@allowhyphens| can be
used.

\DescribeMacro{\allowhyphens}
Same as |\bbl@allowhyphens|, but does nothing if the encoding is
|T1|. It is intended mainly for characters provided as real glyphs by
this encoding but constructed with |\accent| in |OT1|.

Note the previous command (|\bbl@allowhyphens|) has different
applications (hyphens and discretionaries) than this one (composite
chars). Note also prior to version 3.7, |\allowhyphens| had the
behaviour of |\bbl@allowhyphens|.

\DescribeMacro{\set@low@box}
For some languages, quotes need to be lowered to the baseline. For
this purpose the macro |\set@low@box| is available. It takes one
argument and puts that argument in an |\hbox|, at the baseline. The
result is available in |\box0| for further processing.

\DescribeMacro{\save@sf@q}
Sometimes it is necessary to preserve the |\spacefactor|.  For this
purpose the macro |\save@sf@q| is available. It takes one argument,
saves the current spacefactor, executes the argument, and restores the
spacefactor.

\DescribeMacro{\bbl@frenchspacing}
\DescribeMacro{\bbl@nonfrenchspacing}
The commands |\bbl@frenchspacing| and |\bbl@nonfrenchspacing| can be
used to properly switch French spacing on and off.

\subsection{Encoding-dependent strings}
\label{s:strings}

\New{3.9a} Babel 3.9 provides a way of defining strings in several
encodings, intended mainly for \luatex{} and \xetex. This is the only new
feature requiring changes in language files if you want to make use of
it.

Furthermore, it must be activated explicitly, with the package option
|strings|. If there is no |strings|, these blocks are ignored, except
|\SetCase|s (and except if forced as described below). In other words,
the old way of defining/switching strings still works and it's used by
default.

It consist is a series of blocks started with
|\StartBabelCommands|. The last block is closed with
|\EndBabelCommands|. Each block is a single group (ie, local
declarations apply until the next |\StartBabelCommands| or
|\EndBabelCommands|). An |ldf| may contain several series of this
kind.

Thanks to this new feature, string values and string language
switching are not mixed any more. No need of |\addto|. If the language
is |french|, just redefine |\frenchchaptername|.

\Describe\StartBabelCommands
  {\marg{language-list}\marg{category}\oarg{selector}}

The \m{language-list} specifies which languages the block is intended
for. A block is taken into account only if the |\CurrentOption| is
listed here. Alternatively, you can define |\BabelLanguages| to a
comma-separated list of languages to be defined (if undefined,
|\StartBabelCommands| sets it to |\CurrentOption|). You may write
|\CurrentOption| as the language, but this discouraged -- a explicit
name (or names) is much better and clearer.

A ``selector'' is a name to be used as value in package option
|strings|, optionally followed by extra info about the encodings to be
used. The name |unicode| must be used for \xetex{} and \luatex{} (the
key |strings| has also other two special values: |generic| and
|encoded|).

If a string is set several times (because several blocks are read),
the first one take precedence (ie, it works much like
|\providecommand|).

Encoding info is |charset=| followed by a charset, which if given sets
how the strings should be traslated to the internal representation
used by the engine, typically |utf8|, which is the only value
supported currently (default is no traslations). Note |charset| is
applied by \luatex{} and \xetex{} when reading the file, not when the
macro or string is used in the document.

A list of font encodings which the strings are expected to work with
can be given after |fontenc=| (separated with spaces, if two or more) --
recommended, but not mandatory, although blocks without this key are
not taken into account if you have requested |strings=encoded|.

Blocks without a selector are read always if the key |strings| has
been used.  They provide fallback values, and therefore must be the
last blocks; they should be provided always if possible and all
strings should be defined somehow inside it; they can be the only
blocks (mainly LGC scripts using the LICR). Blocks without a selector
can be activated explicitly with |strings=generic| (no block is taken
into account except those). With |strings=encoded|, strings in those
blocks are set as default (internally, |?|). With |strings=encoded|
strings are protected, but they are correctly expanded in
|\MakeUppercase| and the like. If there is no key |strings|, string
definitions are ignored, but |\SetCase|s are still honoured (in a
|encoded| way).

The \m{category} is either |captions|, |date| or |extras|. You must
stick to these three categories, even if no error is raised when using
other name.\footnote{In future releases further categories may be
added.\nb{like `monetary', `time', `address', `name', `case' or
`numeric'}} It may be empty, too, but in such a case using
|\SetString| is an error (but not |\SetCase|).

\begin{verbatim}
\StartBabelCommands{language}{captions}
  [unicode, fontenc=EU1 EU2, charset=utf8]
\SetString{\chaptername}{utf8-string}

\StartBabelCommands{language}{captions}
\SetString{\chaptername}{ascii-maybe-LICR-string}

\EndBabelCommands
\end{verbatim}

A real example is:
\begin{verbatim}[escapechar=\&]
\StartBabelCommands{austrian}{date}
  [unicode, fontenc=EU1 EU2, charset=utf8]
  \SetString\monthiname{J&\"a&nner}

\StartBabelCommands{german,austrian}{date}
  [unicode, fontenc=EU1 EU2, charset=utf8]
  \SetString\monthiiiname{M&\"a&rz}

\StartBabelCommands{austrian}{date}
  \SetString\monthiname{J\"{a}nner}

\StartBabelCommands{german}{date}
  \SetString\monthiname{Januar}

\StartBabelCommands{german,austrian}{date}
  \SetString\monthiiname{Februar}
  \SetString\monthiiiname{M\"{a}rz}
  \SetString\monthivname{April}
  \SetString\monthvname{Mai}
  \SetString\monthviname{Juni}
  \SetString\monthviiname{Juli}
  \SetString\monthviiiname{August}
  \SetString\monthixname{September}
  \SetString\monthxname{Oktober}
  \SetString\monthxiname{November}
  \SetString\monthxiiname{Dezenber}
  \SetString\today{\number\day.~%
    \csname month\romannumeral\month name\endcsname\space
    \number\year}

\StartBabelCommands{german,austrian}{captions}
  \SetString\prefacename{Vorwort}
  [etc.]

\EndBabelCommands
\end{verbatim}

When used in |ldf| files, previous values of |\|\m{category}\m{language}
are overriden, which means the old way to define strings still works
and used by default (to be precise, is first set to undefined and then
strings are added). However, when used in the preamble or in a
package, new settings are added to the previous ones, if the language
exists (in the \babel{} sense, ie, if |\date|\m{language} exists).

\Describe\StartBabelCommands{%
  \colorbox{thegrey}{\ttfamily\hskip-.2em*\hskip-.2em}%
  \marg{language-list}\marg{category}\oarg{selector}}
The starred version just forces |strings| to take a value -- if not set
as package option, then the default for the engine is used. This is
not done by default to prevent backward incompatibilities, but if you
are creating a new language this version is better. It's up to
the maintainers of the current languages to decide if using it is
appropiate.\footnote{This replaces in 3.9g a short-lived
\texttt{\string\UseStrings} which has been removed because it did
not work.}

\Describe\EndBabelCommands{}
Marks the end of the series of blocks.

\Describe\AfterBabelCommands{\marg{code}}
The code is delayed and executed at the global scope just after |\EndBabelCommands|.

\Describe\SetString{\marg{macro-name}\marg{string}}
Adds \meta{macro-name} to the current category, and defines globally
\meta{lang-macro-name} to \meta{code} (after applying the
transformation corresponding to the current charset or defined with
the hook |stringprocess|).

Use this command to define strings, without including any ``logic'' if
possible, which should be a separated macro. See the example above for
the date.

\Describe\SetStringLoop{\marg{macro-name}\marg{string-list}}
A convenient way to define several ordered names at once. For example,
to define |\abmoniname|, |\abmoniiname|, etc. (and similarly with
|abday|):
\begin{verbatim}
\SetStringLoop{abmon#1name}{en,fb,mr,ab,my,jn,jl,ag,sp,oc,nv,dc}
\SetStringLoop{abday#1name}{lu,ma,mi,ju,vi,sa,do}
\end{verbatim}
|#1| is replaced by the roman numeral.

\Describe\SetCase{\oarg{map-list}\marg{toupper-code}\marg{tolower-code}}
Sets globally code to be executed at |\MakeUppercase| and
|\MakeLowercase|. The code would be typically things like |\let\BB\bb|
and |\uccode| or |\lccode| (although for the reasons explained above,
changes in lc/uc codes may not work). A \meta{map-list} is a series of
macros using the internal format of |\@uclclist| (eg,
|\bb\BB\cc\CC|). The mandatory arguments take precedence over the
optional one. This command, unlike |\SetString|, is executed always
(even without |strings|), and it is intented for minor readjustments
only.

For example, as |T1| is the default case mapping in \LaTeX, we could
set for Turkish:
\begin{verbatim}[escapechar=\&]
\StartBabelCommands{turkish}{}[ot1enc, fontenc=OT1]
\SetCase
  {\uccode"10=`I\relax}
  {\lccode`I="10\relax}

\StartBabelCommands{turkish}{}[unicode, fontenc=EU1 EU2, charset=utf8]
\SetCase
  {\uccode`i=`&\rmfamily\.{\ttfamily I}&\relax
   \uccode`&\i&=`I\relax}
  {\lccode`&\rmfamily\.{\ttfamily I}&=`i\relax
   \lccode`I=`&\i&\relax}

\StartBabelCommands{turkish}{}
\SetCase
  {\uccode`i="9D\relax
   \uccode"19=`I\relax}
  {\lccode"9D=`i\relax
   \lccode`I="19\relax}

\EndBabelCommands
\end{verbatim}
(Note the mapping for |OT1| is not complete.)

\Describe\SetHyphenMap{\marg{to-lower-macros}}
\New{3.9g} Case mapping serves in \TeX{} for two unrelated purposes: case
transforms (upper/lower) and hyphenation. |\SetCase| handles the
former, while hyphenation is handled by |\SetHyphenMap| and controlled
with the package option |hyphenmap|. So, even if internally they are based
on the same \TeX{} primitive (|\lccode|), \babel{} sets them separately.

There are three helper macros to
be used inside |\SetHyphenMap|:
\begin{itemize}
\item |\BabelLower|\marg{uccode}\marg{lccode} is
  similar to |\lccode| but it's ignored if the char has been set and
  saves the original lccode to restore it when switching the language
  (except with |hyphenmap=first|).
\item |\BabelLowerMM|\marg{uccode-from}\marg{uccode-to}%
  \marg{step}\marg{lccode-from} loops though the given uppercase
  codes, using the step, and assigns them the lccode, which is also
  increased (|MM| stands for \textit{many-to-many}).
\item |\BabelLowerMO|\marg{uccode-from}\marg{uccode-to}%
  \marg{step}\marg{lccode} loops though the given uppercase
  codes, using the step, and assigns them the lccode, which is fixed
  (|MO| stands for \textit{many-to-one}).
\end{itemize}
An example is (which is redundant, because these assignments are done
by both \luatex{} and \xetex{}):
\begin{verbatim}
\SetHyphenMap{\BabelLowerMM{"100}{"11F}{2}{"101}}
\end{verbatim}

This macro is not intended to fix wrong mappings done by Unicode
(which are the default in both \xetex{} and \luatex{}) -- if an
assignment is wrong, fix it directly.


\section{Compatibility and changes}

\subsection{Compatibility with \file{german.sty}}\label{l-h}

The file \file{german.sty} has been one of the sources of inspiration
for the \babel{} system. Because of this I wanted to include
\file{german.sty} in the \babel{} system.  To be able to do that I had
to allow for one incompatibility: in the definition of the macro
|\selectlanguage| in \file{german.sty} the argument is used as the
{$\langle \it number \rangle$} for an |\ifcase|. So in this case a
call to |\selectlanguage| might look like |\selectlanguage{\german}|.

In the definition of the macro |\selectlanguage| in \file{babel.def}
the argument is used as a part of other macronames, so a call to
|\selectlanguage| now looks like |\selectlanguage{german}|.  Notice
the absence of the escape character.  As of version~3.1a of \babel{}
both syntaxes are allowed.

All other features of the original \file{german.sty} have been copied
into a new file, called \file{germanb.sty}\footnote{The `b' is added
to the name to distinguish the file from Partls' file.}.

Although the \babel{} system was developed to be used with \LaTeX,
some of the features implemented in the language definition files
might be needed by plain \TeX\ users. Care has been taken that all
files in the system can be processed by plain \TeX.

\subsection{Compatibility with \file{ngerman.sty}}

When used with the options \Lopt{ngerman} or \Lopt{naustrian},
\babel{} will provide all features of the package \pkg{ngerman}.
There is however one exception: The commands for special hyphenation
of double consonants (|"ff| etc.) and ck (|"ck|), which are no longer
required with the new German orthography, are undefined. With the
\pkg{ngerman} package, however, these commands will generate
appropriate warning messages only.

\subsection{Compatibility with the \pkg{french} package}

It has been reported to me that the package \pkg{french} by Bernard
Gaulle (\texttt{gaulle@idris.fr}) works together with \babel. On the
other hand, it seems \emph{not} to work well together with a lot of
other packages. Therefore I have decided to no longer load
\file{french.ldf} by default. Instead, when you want to use the
package by Bernard Gaulle, you will have to request it specifically,
by passing either \Lopt{frenchle} or \Lopt{frenchpro} as an option to
\babel.

\subsection{Changes in \babel\ version 3.9}

Most of changes in version 3.9 are related to bugs, either to fix them
(there were lots), or to provide some alternatives. Even new features
like |\babelhyphen| are intended to solve a certain problem (in this
case, the lacking of a uniform syntax and behaviour for shorthands
across languages). These changes are described in this manual in the
correspondin place.

\subsection{Changes in \babel\ version 3.7}

In \babel\ version 3.7 a number of bugs that were found in
version~3.6 are fixed. Also a number of changes and additions
have occurred:
\begin{itemize}
\item Shorthands are expandable again. The disadvantage is that
  one has to type |'{}a| when the acute accent is used as a
  shorthand character. The advantage is that a number of other
  problems (such as the breaking of ligatures, etc.) have
  vanished.
\item Two new commands, |\shorthandon| and |\shorthandoff| have
  been introduced to enable to temporarily switch off one or more
  shorthands.
\item Support for typesetting Greek has been enhanced. Code from
  the \pkg{kdgreek} package (suggested by the author) was added
  and |\greeknumeral| has been added.
\item Support for typesetting Basque is now available thanks to
  Juan Aguirregabiria.
\item Support for typesetting Serbian with Latin script is now
  available thanks to Dejan Muhamedagi\'{c} and Jankovic
  Slobodan.
\item Support for typesetting Hebrew (and potential support for
  typesetting other right-to-left written languages) is now
  available thanks to Rama Porrat and Boris Lavva.
\item Support for typesetting Bulgarian is now available thanks to
  Georgi Boshnakov.
\item Support for typesetting Latin is now available, thanks to
  Claudio Beccari and Krzysztof Konrad \.Zelechowski.
\item Support for typesetting North Sami is now available, thanks
  to Regnor Jernsletten.
\item The options \Lopt{canadian}, \Lopt{canadien} and
  \Lopt{acadien} have been added for Canadian English and French
  use.
\item A language attribute has been added to the |\mark...|
  commands in order to make sure that a Greek header line comes
  out right on the last page before a language switch.
\item Hyphenation pattern files are now read \emph{inside a
  group}; therefore any changes a pattern file needs to make to
  lowercase codes, uppercase codes, and category codes are kept
  local to that group. If they are needed for the language, these
  changes will need to be repeated and stored in |\extras...|
\item The concept of language attributes is introduced. It is
  intended to give the user some control over the
  features a language-definition file provides. Its
  first use is for the Greek language, where the user can choose
  the  $\pi o\lambda\upsilon\tau o\nu\kappa\acute{o}$
  (``Polutoniko'' or multi-accented) Greek way of typesetting
  texts. These attributes will possibly find wider use in future
  releases.
\item The environment \Lenv{hyphenrules} is introduced.
\item The syntax of the file \file{language.dat} has been
  extended to allow (optionally) specifying the font
  encoding to be used while processing the patterns file.
\item The command |\providehyphenmins| should now be used in
  language definition files in order to be able to keep any
  settings provided by the pattern file.
\end{itemize}

\subsection{Changes in \babel\ version 3.6}

In \babel\ version 3.6 a number of bugs that were found in
version~3.5 are fixed. Also a number of changes and additions
have occurred:
\begin{itemize}
\item A new environment \Lenv{otherlanguage*} is introduced. it
  only switches the `specials', but leaves the `captions'
  untouched.
\item The shorthands are no longer fully expandable. Some
  problems could only be solved by peeking at the token following
  an active character. The advantage is that |'{}a| works as
  expected for languages that have the |'| active.
\item Support for typesetting french texts is much enhanced; the
  file \file{francais.ldf} is now replaced by \file{frenchb.ldf}
  which is maintained by Daniel Flipo.
\item Support for typesetting the russian language is again
  available. The language definition file was originally
  developed by Olga Lapko from CyrTUG. The fonts needed to
  typeset the russian language are now part of the \babel\
  distribution. The support is not yet up to the level which is
  needed according to Olga, but this is a start.
\item Support for typesetting greek texts is now also
  available. What is offered in this release is a first attempt;
  it will be enhanced later on by Yannis Haralambous.
\item in \babel\ 3.6j some hooks have been added for the
  development of support for Hebrew typesetting.
\item Support for typesetting texts in Afrikaans (a variant of
  Dutch, spoken in South Africa) has been added to
  \file{dutch.ldf}.
\item Support for typesetting Welsh texts is now available.
\item A new command |\aliasshorthand| is introduced. It seems
  that in Poland various conventions are used to type the
  necessary Polish letters. It is now possible to use the
  character~|/| as a shorthand character instead of the
  character~|"|, by issuing the command |\aliasshorthand{"}{/}|.
\item The shorthand mechanism now deals correctly with characters
  that are already active.
\item Shorthand characters are made active at |\begin{document}|,
  not earlier. This is to prevent problems with other packages.
\item A \emph{preambleonly} command |\substitutefontfamily| has
  been added to create \file{.fd} files on the fly when the font
  families of the Latin text differ from the families used for
  the Cyrillic or Greek parts of the text.
\item Three new commands |\LdfInit|, |\ldf@quit| and
  |\ldf@finish| are introduced that perform a number of standard
  tasks.
\item In babel 3.6k the language Ukrainian has been added and the
  support for Russian typesetting has been adapted to the package
  'cyrillic' to be released with the December 1998 release of
  \LaTeXe.
\end{itemize}

\subsection{Changes in \babel\ version 3.5}

In \babel\ version 3.5 a lot of changes have been made when compared
with the previous release. Here is a list of the most important ones:
\begin{itemize}
\item the selection of the language is delayed until
  |\begin{document}|, which means you must add appropriate
    |\selectlanguage| commands if you include |\hyphenation| lists in
    the preamble of your document.
\item \babel\ now has a \Lenv{language} environment and a new
  command |\foreignlanguage|;
\item the way active characters are dealt with is completely
  changed. They are called `shorthands'; one can have three
  levels of shorthands: on the user level, the language level,
  and on `system level'. A consequence of the new way of handling
  active characters is that they are now written to auxiliary
  files `verbatim';
\item A language change now also writes information in the
  \file{.aux} file, as the change might also affect typesetting
  the table of contents. The consequence is that an \file{.aux} file
  generated by a \LaTeX format with babel preloaded gives errors
  when read with a \LaTeX format without babel; but I think this
  probably doesn't occur;
\item \babel\ is now compatible with the \pkg{inputenc} and
  \pkg{fontenc} packages;
\item the language definition files now have a new extension,
  \file{ldf};
\item the syntax of the file \file{language.dat} is extended to
  be compatible with the \pkg{french} package by Bernard Gaulle;
\item each language definition file looks for a configuration
  file which has the same name, but the extension \file{.cfg}. It
can contain any valid \LaTeX\ code.
\end{itemize}

\DocInput{babel.dtx}
\DocInput{bbunicode.dtx}

\section{Conclusion}

A system of document options has been presented that enable the user
of \LaTeX\ to adapt the standard document classes of \LaTeX\ to the
language he or she prefers to use. These options offer the possibility
of switching between languages in one document. The basic interface
consists of using one option, which is the same for \emph{all}
standard document classes.

In some cases the language definition files provide macros that can be
useful to plain \TeX\ users as well as to \LaTeX\ users.  The \babel{}
system has been implemented so that it can be used by both groups of
users.

\section{Acknowledgements}

I would like to thank all who volunteered as $\beta$-testers for their
time. I would like to mention Julio Sanchez who supplied the option
file for the Spanish language and Maurizio Codogno who supplied the
option file for the Italian language. Michel Goossens supplied
contributions for most of the other languages.  Nico Poppelier helped
polish the text of the documentation and supplied parts of the macros
for the Dutch language.  Paul Wackers and Werenfried Spit helped find
and repair bugs.

During the further development of the babel system I received much
help from Bernd Raichle, for which I am grateful.

\begin{thebibliography}{9}
 \bibitem{DEK} Donald E. Knuth,
   \emph{The \TeX book}, Addison-Wesley, 1986.
 \bibitem{LLbook} Leslie Lamport,
    \emph{\LaTeX, A document preparation System}, Addison-Wesley,
    1986.
 \bibitem{treebus} K.F. Treebus.
    \emph{Tekstwijzer, een gids voor het grafisch verwerken van
    tekst.}
    SDU Uitgeverij ('s-Gravenhage, 1988). A Dutch book on layout
    design and typography.
 \bibitem{HP} Hubert Partl,
   \emph{German \TeX}, \emph{TUGboat} 9 (1988) \#1, p.~70--72.
  \bibitem{LLth} Leslie Lamport,
    in: \TeX hax Digest, Volume 89, \#13, 17 February 1989.
 \bibitem{BEP} Johannes Braams, Victor Eijkhout and Nico Poppelier,
   \emph{The development of national \LaTeX\ styles},
   \emph{TUGboat} 10 (1989) \#3, p.~401--406.
 \bibitem{ilatex} Joachim Schrod,
   \emph{International \LaTeX\ is ready to use},
   \emph{TUGboat} 11 (1990) \#1, p.~87--90.
 \bibitem{ilatex} Apostolos Syropoulos, Antonis Tsolomitis and Nick
   Sofroniu,  
   \emph{Digital typography using \LaTeX},
   Springer, 2002, p.~301--373.
 \bibitem{FE} Yannis Haralambous,
    \emph{Fonts \& Encodings}, O'Reilly, 2007.
\end{thebibliography}
\end{document}
%</filedriver>
%\fi
% \changes{babel~3.7a}{1997/04/16}{Make multiple loading of
%    \file{babel.def} impossible} 
% \changes{babel~3.9a}{2012/05/16}{Now using \cs{ldf@quit} for the test} 
%    \begin{macrocode}
%<*core>
\ifx\ldf@quit\@undefined
\else
  \expandafter\endinput
\fi
%</core>
%    \end{macrocode}
%<*dtx>
\ProvidesFile{babel.dtx}
%</dtx>
%\fi
%
% \GetFileInfo{babel.dtx}
%
% \changes{babel~2.0a}{1990/04/02}{Added text about \file{german.sty}}
% \changes{babel~2.0b}{1990/04/18}{Changed order of code to prevent
%    plain \TeX from seeing all of it}
% \changes{babel~2.1}{1990/04/24}{Modified user interface,
%    \cs{langTeX} no longer necessary}
% \changes{babel~2.1a}{1990/05/01}{Incorporated Nico's comments}
% \changes{babel~2.1b}{1990/05/01}{rename \cs{language} to
%    \cs{current@language}}
% \changes{babel~2.1c}{1990/05/22}{abstract for report fixed, missing
%    \texttt{\}}, found by Nicolas Brouard}
% \changes{babel~2.1d}{1990/07/04}{Missing right brace in definition of
%    abstract environment, found by Werenfried Spit}
% \changes{babel~2.1e}{1990/07/16}{Incorporated more comments from
%    Nico}
% \changes{babel~2.2}{1990/07/17}{Renamed \cs{newlanguage} to
%    \cs{addlanguage}}
% \changes{babel~2.2a}{1990/08/27}{Modified the documentation
%    somewhat}
% \changes{babel~3.0}{1991/04/23}{Moved part of the code to hyphen.doc
%    in preparation for \TeX~3.0}
% \changes{babel~3.0a}{1991/05/21}{Updated comments in various places}
% \changes{babel~3.0b}{1991/05/25}{Removed some problems in change log}
% \changes{babel~3.0c}{1991/07/15}{Renamed \file{babel.sty} and
%    \file{latexhax.sty} to \file{.com}}
% \changes{babel~3.1}{1991/10/31}{Added the support for active
%    characters and for extending a macro}
% \changes{babel~3.1}{1991/11/05}{Removed the need for
%    \file{latexhax}}
% \changes{babel~3.2}{1991/11/10}{Some Changes by br}
% \changes{babel~3.2a}{1992/02/15}{Fixups of the code and
%    documentation}
% \changes{babel~3.3}{1993/07/06}{Included driver file, and prepared
%    for distribution}
% \changes{babel~3.4}{1994/01/30}{Updated for \LaTeXe}
% \changes{babel~3.4}{1994/02/28}{Added language definition file for
%    bahasa}
% \changes{babel~3.4b}{1994/05/18}{Added a small driver to be able to
%    process just this file}
% \changes{babel~3.5a}{1995/02/03}{Provided common code to handle the
%    active double quote}
% \changes{babel~3.5c}{1995/06/14}{corrected a few typos (PR1652)}
% \changes{babel~3.5d}{1995/07/02}{Merged glyphs.dtx into this file}
% \changes{babel~3.5f}{1995/07/13}{repaired a typo}
% \changes{babel~3.5f}{1996/01/09}{replaced \cs{tmp}, \cs{bbl@tmp} and
%    \cs{bbl@temp} with \cs{bbl@tempa}}
% \changes{babel~3.5g}{1996/07/09}{replaced \cs{undefined} with
%    \cs{@undefined} to be consistent with \LaTeX}
% \changes{babel~3.7d}{1999/05/05}{Fixed a few typos in \cs{changes}
%    entries which made typesetting the code impossible}
% \changes{babel~3.7h}{2001/03/01}{Added a number of missing comment
%    characters which caused spurious white space}
% \changes{babel~3.8e}{2005/03/24}{Many enhancements to the text by
%    Andrew Young} 
% \changes{babel~3.9c}{2013/04/04}{Added the ``modifiers'' mechanism}
% \changes{babel~3.9g}{2013/06/01}{bbplain merged}
% \changes{babel~3.9k}{2014/03/23}{Code and doc reorganized, and some
%    minor enhancements}
%\begingroup
%  \catcode`<=\active%
%  \catcode`>=\active
%  \makeatletter
%  \gdef\MakePrivateLetters{%
%    \catcode`@=11\relax
%    \gdef<##1{\ifx##1@$\langle\langle$\bgroup\itshape\rmfamily
%      \expandafter\bblref
%      \else\string<##1\fi}%
%    \gdef\bblref##1@>{##1\/\egroup$\rangle\rangle$}}%
%\endgroup
%
% \part{The code}
%
% \section{Identification and loading of required files}
%
%    \textit{Code documentation is still under revision.}
%
%    The \babel{} package after unpacking it consists of the following files:
%    \begin{description}
%    \itemsep=-\parskip
%    \item[switch.def] defines macros to set and switch languages.
%    \item[babel.def] defines the rest of macros. It has tow parts: a
%    generic one and a second one only for LaTeX{}.
%    \item[babel.sty] is the \LaTeX{} package, which set options and
%    load language styles.
%  \item[plain.def] defines some \LaTeX{} macros required by
%    \file{babel.def} and provides a few tools for Plain.
%   \item[hyphen.cfg] is the file to be used when generating the
%    formats to load hyphenation patterns. By default it also loads
%    \file{suçwitch.def}.
%    \end{description}
%
%    The \babel{} installer extends \textsf{docstrip} with a few
%    ``pseudo-guards'' to set ``variables'' used at installation time.
%    They are used with |<||@name@>| at the appropiated places in the
%    source code and shown below with
%    $\langle\langle$\textit{name}$\rangle\rangle$. That brings a
%    little bit of literate programming.
%
%    \begin{macrocode}
%<<version=3.9l>>
%<<date=2014/09/25>>
%    \end{macrocode}
%
%    We define some basic macros which just make the code cleaner.
%    |\bbl@add| is now used internally instead of |\addto| because of
%    the unpredictable behaviour of the latter. Used in
%    \file{babel.def} and in \file{babel.sty}, which means in \LaTeX{}
%    is executed twice, but we need them when defining options and
%    \file{babel.def} cannot be load until options have been defined.
% \changes{babel~3.9i}{2014/02/16}{\cs{@for} didn't work with
%    Plain. Added \cs{bbl@loop}}
%    \begin{macrocode}
%<<*Basic macros>>
\def\bbl@add#1#2{%
  \@ifundefined{\expandafter\@gobble\string#1}%
    {\def#1{#2}}%
    {\expandafter\def\expandafter#1\expandafter{#1#2}}}
\def\bbl@csarg#1#2{\expandafter#1\csname bbl@#2\endcsname}%
\long\def\bbl@afterelse#1\else#2\fi{\fi#1}
\long\def\bbl@afterfi#1\fi{\fi#1}
\def\bbl@loop#1#2#3{\bbl@@loop#1{#3}#2,\@nnil,}
\def\bbl@loopx#1#2{\expandafter\bbl@loop\expandafter#1\expandafter{#2}}
\def\bbl@@loop#1#2#3,{%
  \ifx\@nnil#3\relax\else
    \def#1{#3}#2\bbl@afterfi\bbl@@loop#1{#2}%
  \fi}
\def\bbl@for#1#2#3{\bbl@loopx#1{#2}{\ifx#1\@empty\else#3\fi}}
%<</Basic macros>>
%    \end{macrocode}
%
%    Some files identify themselves with a \LaTeX{} macro. The following
%    code is placed before them to define (and then undefine) if not in
%    \LaTeX. 
%
%    \begin{macrocode}
%<<*Make sure ProvidesFile is defined>>
\ifx\ProvidesFile\@undefined
  \def\ProvidesFile#1[#2 #3 #4]{%
    \wlog{File: #1 #4 #3 <#2>}%
    \let\ProvidesFile\@undefined}
\fi
%<</Make sure ProvidesFile is defined>>
%    \end{macrocode}
%
%    The following code is used in \file{babel.sty} and
%    \file{babel.def}, and makes sure the current version of
%    |switch.ldf| is used, if different from that in the format. 
%
%    \begin{macrocode}
%<<*Load switch if newer>>
\def\bbl@tempa{<@version@>}%
\ifx\bbl@version\bbl@tempa\else
  \input switch.def\relax
\fi
%<</Load switch if newer>>
%    \end{macrocode}
%
%    The following code is used in \file{babel.def} and
%    \file{switch.def}.
%
%    \begin{macrocode}
%<<*Load macros for plain if not LaTeX>>
\ifx\AtBeginDocument\@undefined
  \input plain.def\relax
\fi
%<</Load macros for plain if not LaTeX>>
%    \end{macrocode}
%
%  \subsection{Multiple languages}
%
%  \begin{macro}{\language}
%    Plain \TeX\ version~3.0 provides the primitive |\language| that
%    is used to store the current language. When used with a pre-3.0
%    version this function has to be implemented by allocating a
%    counter. The following block is used in \file{switch.def} and
%    \file{hyphen.cfg}; the latter may seem redundant, but remember
%    \babel{} doesn't requires loading \file{switch.def} in the format.
%    \begin{macrocode}
%<<*Define core switching macros>>
\ifx\language\@undefined
  \csname newcount\endcsname\language
\fi
%<</Define core switching macros>>
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\last@language}
%    Another counter is used to store the last language defined.  For
%    pre-3.0 formats an extra counter has to be allocated.
%
%  \begin{macro}{\addlanguage}
%
%    To add languages to \TeX's memory plain \TeX\ version~3.0
%    supplies |\newlanguage|, in a pre-3.0 environment a similar macro
%    has to be provided. For both cases a new macro is defined here,
%    because the original |\newlanguage| was defined to be |\outer|.
%
%    For a format based on plain version~2.x, the definition of
%    |\newlanguage| can not be copied because |\count 19| is used for
%    other purposes in these formats. Therefore |\addlanguage| is
%    defined using a definition based on the macros used to define
%    |\newlanguage| in plain \TeX\ version~3.0.
% \changes{babel~3.2}{1991/11/11}{Added a \texttt{\%}, removed
%    \texttt{by}}
%
%    For formats based on plain version~3.0 the definition of
%    |\newlanguage| can be simply copied, removing |\outer|.
%    Plain \TeX\ version 3.0 uses |\count 19| for this purpose.
%    \begin{macrocode}
%<<*Define core switching macros>>
\ifx\newlanguage\@undefined
  \csname newcount\endcsname\last@language
  \def\addlanguage#1{%
    \global\advance\last@language\@ne
    \ifnum\last@language<\@cclvi
    \else
        \errmessage{No room for a new \string\language!}%
    \fi
    \global\chardef#1\last@language
    \wlog{\string#1 = \string\language\the\last@language}}
\else
  \countdef\last@language=19
  \def\addlanguage{\alloc@9\language\chardef\@cclvi}
\fi
%<</Define core switching macros>>
%    \end{macrocode}
%  \end{macro}
%  \end{macro}
%
%    Identify each file that is produced from this source file.
% \changes{babel~3.4c}{1995/04/28}{lhyphen.cfg has become
%    lthyphen.cfg}
% \changes{babel~3.5b}{1995/01/25}{lthyphen.cfg has become hyphen.cfg}
%    \begin{macrocode}
%<*driver&!user>
\ProvidesFile{babel.drv}[<@date@> <@version@>]
%</driver&!user>
%<*driver&user>
\ProvidesFile{user.drv}[<@date@> <@version@>]
%</driver&user>
%    \end{macrocode}
%
%    Now we make sure all required files are loaded.  When the command
%    |\AtBeginDocument| doesn't exist we assume that we are dealing
%    with a plain-based format or \LaTeX2.09. In that case the file
%    \file{plain.def} is needed (which also defines
%    |\AtBeginDocument|, and therefore it is not loaded twice). We
%    need the first part when the format is created, and |\orig@dump|
%    is used as a flag. Otherwise, we need to use the second part, so
%    |\orig@dump| is not defined (\file{plain.def} undefines it).
%
% \changes{babel~3.9a}{2012/12/21}{Use \cs{orig@dump} as flag instead
%    of \cs{adddialect}}
%
%    Check if the current version of \file{switch.def} has been
%    previously loaded (mainly, \file{hyphen.cfg}). If not, load it
%    now. We cannot load |babel.def| here because we first need to
%    declare and process the package options.
% \changes{babel~3.0d}{1991/10/29}{Removed use of \cs{@ifundefined}}
% \changes{babel~3.9a}{2012/08/11}{Now switch.def is loaded always, so
%    that there is no need to rebuild formats just to update babel}
% \changes{babel~3.9a}{2012/12/13}{But switch.def is loaded only if
%    loaded in a different version (or not loaded)}
% \changes{babel~3.9a}{2013/01/14}{Added the debug option}
% \changes{babel~3.9a}{2013/02/05}{Added \cs{bbl@add}}
% \changes{babel~3.6a}{1996/11/02}{Removed \cs{babel@core@loaded}, no
%    longer needed with the advent of \cs{LdfInit}}
%
%    \section{The Package File (\LaTeX)}
%
%    In order to make use of the features of \LaTeXe, the \babel\
%    system contains a package file, \file{babel.sty}. This file is
%    loaded by the |\usepackage| command and defines all the language
%    options whose name is different from that of the |.ldf| file
%    (like variant spellings). It also takes care of a number of
%    compatibility issues with other packages an defines a few
%    aditional package options.
%
%
%    Apart from all the language options below we also have a few options
%    that influence the behaviour of language definition files.
%
%    Many of the following options don't do anything themselves, they
%    are just defined in order to make it possible for babel and
%    language definition files to check if one of them was specified
%    by the user.
%
%   \subsection{\texttt{base}}
%
%    The first option to be processed is |base|, which set the
%    hyphenation patterns then resets |ver@babel.sty| so that
%    \LaTeX forgets about the first loading. After |switch.def| has
%    been loaded (above) and |\AfterBabelLanguage| defined, exits.
%
% \changes{babel~3.5d}{1995/07/04}{Added options to influence
%    behaviour of active acute and grave accents}
% \changes{babel~3.9a}{2012/10/05}{preset option started,
%    party stolen from fontenc}
% \changes{babel~3.9a}{2012/10/17}{Hooks started}
% \changes{babel~3.9a}{2013/02/07}{Rejected preset, and replaced by
%   base}
% \changes{babel~3.5g}{1996/10/10}{We need at least \LaTeX\ from
%    December 1994}
% \changes{babel~3.6k}{1999/03/18}{We need at least \LaTeX\ from
%    June 1998}
%    \begin{macrocode}
%<*package>
\NeedsTeXFormat{LaTeX2e}[2005/12/01]
\ProvidesPackage{babel}[<@date@> <@version@> The Babel package]
\@ifpackagewith{babel}{debug}
 {\input switch.def\relax}
 {<@Load switch if newer@>}
<@Basic macros@>
\def\AfterBabelLanguage#1{%
  \global\expandafter\bbl@add\csname#1.ldf-h@@k\endcsname}%
\@ifpackagewith{babel}{base}{%
  \DeclareOption*{\bbl@patterns{\CurrentOption}}%
  \DeclareOption{base}{}%
  \ProcessOptions
  \global\expandafter\let\csname opt@babel.sty\endcsname\relax
  \global\expandafter\let\csname ver@babel.sty\endcsname\relax
  \global\let\@ifl@ter@@\@ifl@ter
  \def\@ifl@ter#1#2#3#4#5{\global\let\@ifl@ter\@ifl@ter@@}%
  \endinput}{}%
%    \end{macrocode}
%
%    \subsection{\texttt{key=value} options and other general option}
%
%    The following macros extract language modifiers, and only real
%    package options are kept in the option list. Modifiers are saved
%    and assigned to |\BabelModifiers| at |\bbl@load@language|; when
%    no modifiers have been given, the former is |\relax|. How
%    modifiers are handled are left to language styles; they can use
%    |\in@|, loop them with |\@for| o load |keyval|).
% \changes{babel~3.9e}{2013/04/15}{Bug fixed - a dot was added in
%    key=value pairs}
%
%    \begin{macrocode}
\bbl@csarg\let{tempa\expandafter}\csname opt@babel.sty\endcsname
\def\bbl@tempb#1.#2{%
   #1\ifx\@empty#2\else,\bbl@afterfi\bbl@tempb#2\fi}%
\def\bbl@tempd#1.#2\@nnil{%
  \ifx\@empty#2%
    \edef\bbl@tempc{\ifx\bbl@tempc\@empty\else\bbl@tempc,\fi#1}%
  \else
    \in@{=}{#1}\ifin@
      \edef\bbl@tempc{\ifx\bbl@tempc\@empty\else\bbl@tempc,\fi#1.#2}%
    \else
      \edef\bbl@tempc{\ifx\bbl@tempc\@empty\else\bbl@tempc,\fi#1}%
      \bbl@csarg\edef{mod@#1}{\bbl@tempb#2}%
    \fi
  \fi}
\let\bbl@tempc\@empty
\bbl@for\bbl@tempa\bbl@tempa{%
  \expandafter\bbl@tempd\bbl@tempa.\@empty\@nnil}
\expandafter\let\csname opt@babel.sty\endcsname\bbl@tempc
%    \end{macrocode}
%    The next option tells \babel\ to leave shorthand characters
%    active at the end of processing the package. This is \emph{not}
%    the default as it can cause problems with other packages, but for
%    those who want to use the shorthand characters in the preamble of
%    their documents this can help.
% \changes{babel~3.6f}{1997/01/14}{Added option
%    \Lopt{KeepShorthandsActive}}
% \changes{babel~3.7a}{1997/03/21}{No longer define the control
%    sequence \cs{KeepShorthandsActive}}
% \changes{babel~3.9a}{2012/08/14}{Implemented the \texttt{noconfigs}
%    option}
% \changes{babel~3.9a}{2012/09/26}{Implemented the
%    \texttt{showlanguages} option}
% \changes{babel~3.9g}{2013/08/07}{Options for hyphenmap}
% \changes{babel~3.9l}{2014/07/29}{Option \texttt{silent}}
%    \begin{macrocode}
\DeclareOption{KeepShorthandsActive}{}
\DeclareOption{activeacute}{}
\DeclareOption{activegrave}{}
\DeclareOption{debug}{}
\DeclareOption{noconfigs}{}
\DeclareOption{showlanguages}{}
\DeclareOption{silent}{}
\DeclareOption{shorthands=off}{\bbl@tempa shorthands=\bbl@tempa}
<@More package options@>
%    \end{macrocode}
%
%    Handling of package options is done in three passes. (I [JBL] am not
%    very happy with the idea, anyway.) The first one processes
%    options which has been declared above or follow the syntax
%    |<key>=<value>|, the second one 
%    loads the requested languages, except the main one if set with
%    the key |main|, and the third one loads the latter. First, we
%    ``flag'' valid keys with a nil value.
% \changes{babel~3.9a}{2012/08/10}{Added the `safe' key, including code
%    below for selecting the redefined macros}
%    \begin{macrocode}
\let\bbl@opt@shorthands\@nnil
\let\bbl@opt@config\@nnil
\let\bbl@opt@main\@nnil
\let\bbl@opt@headfoot\@nnil
%    \end{macrocode}
%    The following tool is defined temporarily to store the values of
%    options.
%    \begin{macrocode}
\def\bbl@tempa#1=#2\bbl@tempa{%
  \expandafter\ifx\csname bbl@opt@#1\endcsname\@nnil
    \expandafter\edef\csname bbl@opt@#1\endcsname{#2}%
  \else
    \bbl@error{%
      Bad option `#1=#2'. Either you have misspelled the\\%
      key or there is a previous setting of `#1'}{%
      Valid keys are `shorthands', `config', `strings', `main',\\%
      `headfoot', `safe', `math'}
  \fi}
%    \end{macrocode}
%    Now the option list is processed, taking into account only
%    currently declared options (including those declared with a |=|),
%    and |<key>=<value>| options (the former take precedence). 
%    Unrecognized options are saved in |\bbl@language@opts|, because
%    they are language options. 
%    \begin{macrocode}
\let\bbl@language@opts\@empty
\DeclareOption*{%
  \@expandtwoargs\in@{\string=}{\CurrentOption}%
  \ifin@
    \expandafter\bbl@tempa\CurrentOption\bbl@tempa
  \else
    \edef\bbl@language@opts{%
      \ifx\bbl@language@opts\@empty\else\bbl@language@opts,\fi
      \CurrentOption}%
  \fi}
%    \end{macrocode}
%    Now we finish the first pass (and start over).
%    \begin{macrocode}
\ProcessOptions*
%    \end{macrocode}
%
%    \subsection{Conditional loading of shorthands}
%
%    If there is no |shorthands=<chars>|, the original \textsf{babel}
%    macros are left untouched, but if there is, these macros are
%    wrapped (in |babel.def|) to define only those given.
%
%    A bit of optimization: if there is no |shorthands=|, then
%    |\bbl@ifshorthands| is always true, and it is always false if
%    |shorthands| is empty. Also, some code makes sense only with
%    |shorthands=...|.  
% \changes{babel~3.9c}{2013/04/07}{Added t and c for tilde and comma}
%    \begin{macrocode}
\def\bbl@sh@string#1{%
  \ifx#1\@empty\else
    \ifx#1t\string~%
    \else\ifx#1c\string,%
    \else\string#1%
    \fi\fi
    \expandafter\bbl@sh@string
  \fi}
\ifx\bbl@opt@shorthands\@nnil
  \def\bbl@ifshorthand#1#2#3{#2}%
\else\ifx\bbl@opt@shorthands\@empty
  \def\bbl@ifshorthand#1#2#3{#3}%
\else
%    \end{macrocode}
%    The following macro tests if a shortand is one of the allowed
%    ones.
%    \begin{macrocode}
  \def\bbl@ifshorthand#1{%
    \@expandtwoargs\in@{\string#1}{\bbl@opt@shorthands}%
    \ifin@
      \expandafter\@firstoftwo
    \else
      \expandafter\@secondoftwo
    \fi}
%    \end{macrocode}
%    We make sure all chars in the string are `other', with the help
%    of an auxiliary macro defined above (which also zaps spaces).
%    \begin{macrocode}
  \edef\bbl@opt@shorthands{%
    \expandafter\bbl@sh@string\bbl@opt@shorthands\@empty}%
%    \end{macrocode}
%
%    The following is ignored with |shorthands=off|, since it is
%    intended to take some aditional actions for certain chars.
%
%    \begin{macrocode}
  \bbl@ifshorthand{'}%
    {\PassOptionsToPackage{activeacute}{babel}}{}
  \bbl@ifshorthand{`}%
    {\PassOptionsToPackage{activegrave}{babel}}{}
\fi\fi
%    \end{macrocode}
% \changes{babel~3.9a}{2012/07/30}{Code setting language in
%    head/foots.  Related to babel/3796}
%    With |headfoot=lang| we can set the language used in heads/foots.         
%    For example, in babel/3796 just adds |headfoot=english|.  It
%    misuses \cs{@resetactivechars} but seems to work.
%    \begin{macrocode}
\ifx\bbl@opt@headfoot\@nnil\else
  \g@addto@macro\@resetactivechars{%
    \set@typeset@protect                  
    \expandafter\select@language@x\expandafter{\bbl@opt@headfoot}%
    \let\protect\noexpand}
\fi
%    \end{macrocode}
%    For the option safe we use a different approach --
%    |\bbl@opt@safe| says which macros are redefined (B for bibs and R
%    for refs). By default, both are set. 
%    \begin{macrocode}
\@ifundefined{bbl@opt@safe}{\def\bbl@opt@safe{BR}}{}
\ifx\bbl@opt@main\@nnil\else
  \edef\bbl@language@opts{%
    \ifx\bbl@language@opts\@empty\else\bbl@language@opts,\fi
      \bbl@opt@main}
\fi
%    \end{macrocode}
%    If the format created a list of loaded languages (in
%    |\bbl@languages|), get the name of the 0-th to show the actual
%    language used.
%    \begin{macrocode}
\ifx\bbl@languages\@undefined\else
  \begingroup
    \catcode`\^^I=12
    \@ifpackagewith{babel}{showlanguages}{%
      \begingroup
        \def\bbl@elt#1#2#3#4{\wlog{#2^^I#1^^I#3^^I#4}}%
        \wlog{<*languages>}%
        \bbl@languages
        \wlog{</languages>}%
      \endgroup}{}
  \endgroup
  \def\bbl@elt#1#2#3#4{%
    \ifnum#2=\z@
      \gdef\bbl@nulllanguage{#1}%
      \def\bbl@elt##1##2##3##4{}%
    \fi}%
  \bbl@languages
\fi
%    \end{macrocode}
%
%  \subsection{Language options}
%
% \changes{babel~3.6c}{1997/01/05}{When \cs{LdfInit} is undefined we
%    need to load \file{babel.def} from \file{babel.sty}}
% \changes{babel~3.6l}{1999/04/03}{Don't load \file{babel.def} now,
%    but rather define \cs{LdfInit} temporarily in order to load
%    \file{babel.def} at the right time, preventing problems with the
%    temporary definition of \cs{bbl@redefine}}
% \changes{babel~3.6r}{1999/04/12}{We \textbf{do} need to load
%    \file{babel.def} right now as \cs{ProvidesLanguage} needs to be
%    defined before the \file{.ldf} files are read and the reason for
%    for 3.6l has been removed}
% \changes{babel~3.9a}{2012/06/15}{Rewritten the loading mechanism, so
%    that languages not declared are also correctly recognized, even
%    if given as global options} 
% \changes{babel~3.9a}{2012/08/12}{Revised the loading mechanism}
% \changes{babel~3.5a}{1995/03/14}{Changed extension of language
%    definition files to \texttt{ldf}}
% \changes{babel~3.5d}{1995/07/02}{Load language definition files
%    \emph{after} the check for the hyphenation patterns}
% \changes{babel~3.5g}{1996/10/04}{Added option \Lopt{afrikaans}}
% \changes{babel~3.7g}{2001/02/09}{Added option \Lopt{acadian}}
% \changes{babel~3.8c}{2004/06/12}{Added option \Lopt{australian}}
% \changes{babel~3.8h}{2005/11/23}{Added option \Lopt{albanian}}
% \changes{babel~3.6i}{1997/02/20}{Added the \Lopt{Basque} option}
% \changes{babel~3.8h}{2005/11/23}{added synonyms \Lopt{indonesian},
%    \Lopt{indon} and \Lopt{bahasai} for the original bahasa
%    (indonesia) support}
% \changes{babel~3.8h}{2005/11/23}{added \Lopt{malay}, \Lopt{meyaluy}
%    and \Lopt{bahasam} for the Bahasa Malaysia support}
% \changes{babel~3.5b}{1995/05/25}{Added \Lopt{brazilian} as
%    alternative for \Lopt{brazil}}
% \changes{babel~3.5d}{1995/07/02}{Added \Lopt{british} as an
%    alternative for \Lopt{english} with a preference for british
%    hyphenation}
% \changes{babel~3.7f}{2000/09/21}{Added the \Lopt{bulgarian} option}
% \changes{babel~3.7g}{2001/02/07}{Added option \Lopt{canadian}}
% \changes{babel~3.7g}{2001/02/09}{Added option \Lopt{canadien}}
% \changes{babel~3.5b}{1995/06/06}{Added the \Lopt{estonian} option}
% \changes{babel~3.5f}{1996/01/10}{Now use the file \file{frenchb.ldf}
%    from Daniel Flipo for french support}
% \changes{babel~3.6e}{1997/01/08}{Added option \Lopt{frenchb} an
%    alias for \Lopt{francais}}
% \changes{babel~3.5d}{1995/07/02}{Load \file{french.ldf} when it is
%    found instead of \file{frenchb.ldf}}
% \changes{babel~3.7j}{2003/06/07}{\emph{only} load
%    \file{frenchb.ldf}}
% \changes{babel~3.5f}{1996/05/31}{Added the \Lopt{greek} option}
% \changes{babel~3.7a}{1997/11/13}{Added the \Lopt{polutonikogreek}
%    option}
% \changes{babel~3.7c}{1999/04/22}{set the correct language attribute
%    for polutoniko greek}
% \changes{babel~3.7a}{1998/03/27}{Added the \Lopt{hebrew} option}
% \changes{babel~3.7b}{1998/06/25}{Added the \Lopt{latin} option}
% \changes{babel~3.7m}{2003/11/13}{Added the \Lopt{interlingua}
%    option}
% \changes{babel~3.6p}{1999/04/10}{Added the \Lopt{ngerman} and
%    \Lopt{naustrian} options}
% \changes{babel~3.7f}{2000/09/26}{Added the \Lopt{samin} option}
% \changes{babel~3.8c}{2004/06/12}{Added the \Lopt{newzealand} option}
% \changes{babel~3.6e}{1997/01/08}{Added options \Lopt{UKenglish} and
%    \Lopt{USenglish}}
% \changes{babel~3.9i}{2014/03/01}{Removed German options, because
%    they are now loaded directly}
%
%    Languages are loaded when processing the corresponding option
%    \textit{except} if a |main| language has been set. In such a
%    case, it is not loaded until all options has been processed.
%    The following macro inputs the ldf file and does some additional
%    checks (|\input| works, too, but possible errors are not catched).
%    \begin{macrocode}
\let\bbl@afterlang\relax
\let\BabelModifiers\relax
\let\bbl@loaded\@empty
\def\bbl@load@language#1{%
  \InputIfFileExists{#1.ldf}%
    {\edef\bbl@loaded{\CurrentOption
       \ifx\bbl@loaded\@empty\else,\bbl@loaded\fi}%
     \expandafter\let\expandafter\bbl@afterlang
        \csname\CurrentOption.ldf-h@@k\endcsname
     \expandafter\let\expandafter\BabelModifiers
        \csname bbl@mod@\CurrentOption\endcsname}%
    {\bbl@error{%
       Unknown option `\CurrentOption'. Either you misspelled it\\%
       or the language definition file \CurrentOption.ldf was not found}{%
       Valid options are: shorthands=, KeepShorthandsActive,\\%
       activeacute, activegrave, noconfigs, safe=, main=, math=\\%
       headfoot=, strings=, config=, hyphenmap=, or a language name.}}}
%    \end{macrocode}
%    Now, we set language options whose names are different from |ldf| files.
%    \begin{macrocode}
\DeclareOption{acadian}{\bbl@load@language{frenchb}}
\DeclareOption{afrikaans}{\bbl@load@language{dutch}}
\DeclareOption{american}{\bbl@load@language{english}}
\DeclareOption{australian}{\bbl@load@language{english}}
\DeclareOption{bahasa}{\bbl@load@language{bahasai}}
\DeclareOption{bahasai}{\bbl@load@language{bahasai}}
\DeclareOption{bahasam}{\bbl@load@language{bahasam}}
\DeclareOption{brazil}{\bbl@load@language{portuges}}
\DeclareOption{brazilian}{\bbl@load@language{portuges}}
\DeclareOption{british}{\bbl@load@language{english}}
\DeclareOption{canadian}{\bbl@load@language{english}}
\DeclareOption{canadien}{\bbl@load@language{frenchb}}
\DeclareOption{francais}{\bbl@load@language{frenchb}}
\DeclareOption{french}{\bbl@load@language{frenchb}}%
\DeclareOption{hebrew}{%
  \input{rlbabel.def}%
  \bbl@load@language{hebrew}}
\DeclareOption{hungarian}{\bbl@load@language{magyar}}
\DeclareOption{indon}{\bbl@load@language{bahasai}}
\DeclareOption{indonesian}{\bbl@load@language{bahasai}}
\DeclareOption{lowersorbian}{\bbl@load@language{lsorbian}}
\DeclareOption{malay}{\bbl@load@language{bahasam}}
\DeclareOption{meyalu}{\bbl@load@language{bahasam}}
\DeclareOption{newzealand}{\bbl@load@language{english}}
\DeclareOption{nynorsk}{\bbl@load@language{norsk}}
\DeclareOption{polutonikogreek}{%
  \bbl@load@language{greek}%
  \languageattribute{greek}{polutoniko}}
\DeclareOption{portuguese}{\bbl@load@language{portuges}}
\DeclareOption{russian}{\bbl@load@language{russianb}}
\DeclareOption{UKenglish}{\bbl@load@language{english}}
\DeclareOption{ukrainian}{\bbl@load@language{ukraineb}}
\DeclareOption{uppersorbian}{\bbl@load@language{usorbian}}
\DeclareOption{USenglish}{\bbl@load@language{english}}
%    \end{macrocode}
%
%    Another way to extend the list of `known' options for \babel\ is
%    to create the file \file{bblopts.cfg} in which one can add option
%    declarations. However, this mechanism is deprecated -- if you
%    want an alternative name for a language, just create a new |.ldf|
%    file loading the actual one. You can also set the name
%    of the file with the package option |config=<name>|, which will
%    load |<name>.cfg| instead. 
% \changes{babel~3.6i}{1997/03/15}{Added the possibility to have a
%    \file{bblopts.cfg} file with option declarations.}
% \changes{babel~3.9a}{2012/06/28}{Added the \cs{AfterBabelLanguage}
%    mechanism, to be used mainly with the local cfg file.}
% \changes{babel~3.9a}{2012/06/31}{Now you can set the name of the
%    local cfg file.}
%    \begin{macrocode}
\ifx\bbl@opt@config\@nnil
  \@ifpackagewith{babel}{noconfigs}{}%
    {\InputIfFileExists{bblopts.cfg}%
      {\typeout{*************************************^^J%
               * Local config file bblopts.cfg used^^J%
               *}}%
      {}}%
\else
  \InputIfFileExists{\bbl@opt@config.cfg}%
    {\typeout{*************************************^^J%
             * Local config file \bbl@opt@config.cfg used^^J%
             *}}%
    {\bbl@error{%
       Local config file `\bbl@opt@config.cfg' not found}{%
       Perhaps you misspelled it.}}%
\fi
%    \end{macrocode}
%
%    Recognizing global options in packages not having a closed set of
%    them is not trivial, as for them to be processed they must be
%    defined explicitly. So, package options not yet taken into
%    account and stored in |bbl@language@opts| are assumed to be
%    languages (note this list also contains the language given with
%    |main|). If not declared above, the name of the option and the
%    file are the same.
%    \begin{macrocode}
\bbl@for\bbl@tempa\bbl@language@opts{%
  \@ifundefined{ds@\bbl@tempa}%
    {\edef\bbl@tempb{%
       \noexpand\DeclareOption
         {\bbl@tempa}%
         {\noexpand\bbl@load@language{\bbl@tempa}}}%
     \bbl@tempb}%
     \@empty}
%    \end{macrocode}
%    Now, we make sure an option is explicitly declared for any
%    language set as global option, by checking if an |ldf|
%    exists. The previous step was, in fact, somewhat redundant, but
%    that way we minimize accesing the file system just to see if the
%    option could be a language.
%    \begin{macrocode}
\bbl@for\bbl@tempa\@classoptionslist{%
  \@ifundefined{ds@\bbl@tempa}%
    {\IfFileExists{\bbl@tempa.ldf}%
      {\edef\bbl@tempb{%
         \noexpand\DeclareOption
           {\bbl@tempa}%
           {\noexpand\bbl@load@language{\bbl@tempa}}}%
       \bbl@tempb}%
      \@empty}%
    \@empty}
%    \end{macrocode}
%    If a main language has been set, store it for the third pass.
%    \begin{macrocode}
\ifx\bbl@opt@main\@nnil\else
  \expandafter
  \let\expandafter\bbl@loadmain\csname ds@\bbl@opt@main\endcsname
  \DeclareOption{\bbl@opt@main}{}
\fi
%    \end{macrocode}
%    And we are done, because all options for this pass has been
%    declared. Those already processed in the first pass are just ignored.
% \changes{babel~3.6i}{1997/03/12}{Added default option}
% \changes{babel~3.9a}{2012/12/22}{Default option does nothing}
%
%    The options have to be processed in the order in which the user
%    specified them (except, of course, global options, which \LaTeX{}
%    processes before):
%    \begin{macrocode}
\def\AfterBabelLanguage#1{%
  \bbl@ifsamestring\CurrentOption{#1}{\global\bbl@add\bbl@afterlang}{}}
\DeclareOption*{}
\ProcessOptions*
%    \end{macrocode}
%    This finished the second pass. Now the third one begins, which
%    loads the main language set with the key |main|. A warning is
%    raised if the main language is not the same as the last named
%    one, or if the value of the key |main| is not a language. Then
%    execute directly the option (because it could be used only in
%    |main|). After loading all languages, we deactivate
%    |\AfterBabelLanguage|.
%    \begin{macrocode}
\ifx\bbl@opt@main\@nnil
  \edef\bbl@tempa{\@classoptionslist,\bbl@language@opts}
  \let\bbl@tempc\@empty
  \bbl@for\bbl@tempb\bbl@tempa{%
    \@expandtwoargs\in@{,\bbl@tempb,}{,\bbl@loaded,}%
    \ifin@\edef\bbl@tempc{\bbl@tempb}\fi}
  \def\bbl@tempa#1,#2\@nnil{\def\bbl@tempb{#1}}
  \expandafter\bbl@tempa\bbl@loaded,\@nnil
  \ifx\bbl@tempb\bbl@tempc\else
    \bbl@warning{%
      Last declared language option is `\bbl@tempc,\\%
      but the last processed one was `\bbl@tempb'.\\%
      The main language cannot be set as both a global\\%
      and a package option. Use `main=\bbl@tempc' as\\%
      option. Reported}%
  \fi
\else
  \DeclareOption{\bbl@opt@main}{\bbl@loadmain}
  \ExecuteOptions{\bbl@opt@main}
  \DeclareOption*{}
  \ProcessOptions*
\fi
\def\AfterBabelLanguage{%
  \bbl@error
    {Too late for \string\AfterBabelLanguage}%
    {Languages have been loaded, so I can do nothing}}
%    \end{macrocode}
% \changes{babel~3.7c}{1999/03/13}{Added an error message for when no
%    language option was specified}
%    In order to catch the case where the user forgot to specify a
%    language we check whether |\bbl@main@language|, has become
%    defined. If not, no language has been loaded and an error
%    message is displayed.
% \changes{babel~3.7c}{1999/04/09}{No longer us a redefinition of an
%    internal macro, just check \cs{bbl@main@language} and load
%    \file{babel.def}}
% \changes{babel~3.9a}{2012/06/24}{Now babel is not loaded to prevent
%    the document from raising errors after fixing it}
%    \begin{macrocode}
\ifx\bbl@main@language\@undefined
  \bbl@error{%
    You haven't specified a language option}{%
    You need to specify a language, either as a global option\\%
    or as an optional argument to the \string\usepackage\space
    command;\\%
    You shouldn't try to proceed from here, type x to quit.}
\fi
%</package>
%    \end{macrocode}
%
%    \section{The kernel of Babel (common)}
%
%    The kernel of the \babel\ system is stored in either
%    \file{hyphen.cfg} or \file{switch.def} and \file{babel.def}.  The
%    file \file{babel.def} contains most of the code, while
%    \file{switch.def} defines the language switching commands; both
%    can be read at run time. The file \file{hyphen.cfg} is a file
%    that can be loaded into the format, which is necessary when you
%    want to be able to switch hyphenation patterns (by default, it
%    also inputs \file{switch.def}, for ``historical reasons'', but it
%    is not necessary). When \file{babel.def} is loaded it checks if
%    the current version of \file{switch.def} is in the format; if not
%    it is loaded. A further file, \file{babel.sty}, contains
%    \LaTeX-specific stuff.
%
%    Because plain \TeX\ users might want to use some of the features
%    of the \babel{} system too, care has to be taken that plain \TeX\
%    can process the files. For this reason the current format will
%    have to be checked in a number of places. Some of the code below
%    is common to plain \TeX\ and \LaTeX, some of it is for the
%    \LaTeX\ case only.
%
%    Plain formats based on etex (etex, xetex, luatex) don't load
%    |hyphen.cfg| but |etex.src|, which follows a different naming
%    convention, so we need to define the babel names. It presumes
%    |language.def| exists and it is the same file used when
%    formats were created.
%
% \changes{babel~3.9a}{2013/01/11}{Added \cs{bbl@for} for loops
%    ignoring empties}
% \changes{babel~3.9c}{2013/04/06}{Normalize \cs{bbl@afterlang} to
%    relax}
% \changes{babel~3.9i}{2014/03/10}{Make sure \cs{bbl@language@opts}
%    is defined.}
% \changes{babel~3.9i}{2014/03/11}{Define \cs{l@} values from
%   \cs{lang@} values set in Plain etex/xetex/luatex}
%
%    \subsection{Tools}
%
%    |\bbl@engine| takes the following values: 0 is pdf\TeX, 1 is
%    \luatex, and 2 is \xetex. You may use it in your language style
%    if necessary.
%
% \changes{babel~3.9k}{2014/03/24}{Added definition for \cs{uselanguage}}
%
%    \begin{macrocode}
%<*core>
<@Make sure ProvidesFile is defined@>
\ProvidesFile{babel.def}[<@date@> <@version@> Babel common definitions]
<@Load macros for plain if not LaTeX@>
<@Load switch if newer@>
\ifx\bbl@languages\@undefined
  \openin1 = language.def
  \ifeof1
    \closein1
    \message{I couldn't find the file language.def}
  \else
    \closein1
    \begingroup
      \def\addlanguage#1#2#3#4#5{%
        \expandafter\ifx\csname lang@#1\endcsname\relax\else
          \global\expandafter\let\csname l@#1\expandafter\endcsname
            \csname lang@#1\endcsname
        \fi}%
      \def\uselanguage#1{}%
      \input language.def
    \endgroup
  \fi
  \chardef\l@english\z@
\fi
<@Basic macros@>
\def\bbl@csarg#1#2{\expandafter#1\csname bbl@#2\endcsname}%
\chardef\bbl@engine=%
  \ifx\directlua\@undefined
    \ifx\XeTeXinputencoding\@undefined
      \z@
    \else
      \tw@
    \fi
  \else
    \@ne
  \fi
%    \end{macrocode}
%
%  \begin{macro}{\bbl@afterelse}
%  \begin{macro}{\bbl@afterfi}
%    Because the code that is used in the handling of active
%    characters may need to look ahead, we take extra care to `throw'
%    it over the |\else| and |\fi| parts of an
%    |\if|-statement\footnote{This code is based on code presented in
%    TUGboat vol. 12, no2, June 1991 in ``An expansion Power Lemma''
%    by Sonja Maus.}. These macros will break if another |\if...\fi|
%    statement appears in one of the arguments and it is not enclosed
%    in braces.
% \changes{babel~3.6i}{1997/02/20}{Made \cs{bbl@afterelse} and
%    \cs{bbl@afterfi} \cs{long}}
%    \begin{macrocode}
\long\def\bbl@afterelse#1\else#2\fi{\fi#1}
\long\def\bbl@afterfi#1\fi{\fi#1}
%    \end{macrocode}
%  \end{macro}
%  \end{macro}
%
%  \begin{macro}{\addto}
%    For each language four control sequences have to be defined that
%    control the language-specific definitions. To be able to add
%    something to these macro once they have been defined the macro
%    |\addto| is introduced. It takes two arguments, a \meta{control
%    sequence} and \TeX-code to be added to the \meta{control
%    sequence}.
%
%    If the \meta{control sequence} has not been defined before it is
%    defined now.  The control sequence could also expand to |\relax|,
%    in which case a circular definition results. The net result is a
%    stack overflow.  Otherwise the replacement text for the
%    \meta{control sequence} is expanded and stored in a token
%    register, together with the \TeX-code to be added.  Finally the
%    \meta{control sequence} is \emph{re}defined, using the contents
%    of the token register.
%
% \changes{babel~3.1}{1991/11/05}{Added macro}
% \changes{babel~3.4}{1994/02/04}{Changed to use toks register}
% \changes{babel~3.6b}{1996/12/30}{Also check if control sequence
%    expands to \cs{relax}}
%    \begin{macrocode}
\def\addto#1#2{%
  \ifx#1\@undefined
    \def#1{#2}%
  \else
    \ifx#1\relax
      \def#1{#2}%
    \else
      {\toks@\expandafter{#1#2}%
       \xdef#1{\the\toks@}}%
    \fi
  \fi}
%    \end{macrocode}
%  \end{macro}
%
% \changes{babel~3.9a}{2012/08/10}{Removed the \cs{peek@token} and
%    \textsc{test@token} stuff}
%    The macro |\initiate@active@char| takes all the necessary actions
%    to make its argument a shorthand character. The real work is
%    performed once for each character.
% \changes{babel~3.7c}{1999/04/30}{Only execute
%    \cs{initiate@active@char} once for each character}
% \changes{babel~3.9a}{1999/04/30}{Added \cs{bbl@withactive}}
%    \begin{macrocode}
\def\bbl@withactive#1#2{%
  \begingroup
    \lccode`~=`#2\relax
    \lowercase{\endgroup#1~}}
%    \end{macrocode}
%
%
%  \begin{macro}{\bbl@redefine}
% \changes{babel~3.5f}{1995/11/15}{Macro added}
%    To redefine a command, we save the old meaning of the macro.
%    Then we redefine it to call the original macro with the
%    `sanitized' argument.  The reason why we do it this way is that
%    we don't want to redefine the \LaTeX\ macros completely in case
%    their definitions change (they have changed in the past).
%
%    Because we need to redefine a number of commands we define the
%    command |\bbl@redefine| which takes care of this. It creates a
%    new control sequence, |\org@...|
%    \begin{macrocode}
\def\bbl@redefine#1{%
  \edef\bbl@tempa{\expandafter\@gobble\string#1}%
  \expandafter\let\csname org@\bbl@tempa\endcsname#1%
  \expandafter\def\csname\bbl@tempa\endcsname}
%    \end{macrocode}
%
%    This command should only be used in the preamble of the document.
%    \begin{macrocode}
\@onlypreamble\bbl@redefine
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\bbl@redefine@long}
% \changes{babel~3.6f}{1997/01/14}{Macro added}
%    This version of |\babel@redefine| can be used to redefine |\long|
%    commands such as |\ifthenelse|.
%    \begin{macrocode}
\def\bbl@redefine@long#1{%
  \edef\bbl@tempa{\expandafter\@gobble\string#1}%
  \expandafter\let\csname org@\bbl@tempa\endcsname#1%
  \expandafter\long\expandafter\def\csname\bbl@tempa\endcsname}
\@onlypreamble\bbl@redefine@long
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\bbl@redefinerobust}
% \changes{babel~3.5f}{1995/11/15}{Macro added}
% \changes{babel~3.5f}{1996/04/09}{Define \cs*{foo } instead of
%    \cs{foo}}
%    For commands that are redefined, but which \textit{might} be
%    robust we need a slightly more intelligent macro. A robust
%    command |foo| is defined to expand to |\protect|\verb*|\foo |. So
%    it is necessary to check whether \verb*|\foo | exists. The result
%    is that the command that is being redefined is always robust
%    afterwards.  Therefore all we need to do now is define \verb*|\foo |.
%    \begin{macrocode}
\def\bbl@redefinerobust#1{%
  \edef\bbl@tempa{\expandafter\@gobble\string#1}%
  \expandafter\ifx\csname\bbl@tempa\space\endcsname\relax
    \expandafter\let\csname org@\bbl@tempa\endcsname#1%
    \expandafter\edef\csname\bbl@tempa\endcsname{\noexpand\protect
      \expandafter\noexpand\csname\bbl@tempa\space\endcsname}%
  \else
    \expandafter\let\csname org@\bbl@tempa\expandafter\endcsname
                    \csname\bbl@tempa\space\endcsname
  \fi
  \expandafter\def\csname\bbl@tempa\space\endcsname}
%    \end{macrocode}
%
%    This command should only be used in the preamble of the document.
%    \begin{macrocode}
\@onlypreamble\bbl@redefinerobust
%    \end{macrocode}
%  \end{macro}
%
%  \subsection{Hooks}
%
%  Note they are loaded in babel.def. switch.def only provides a
%  ``hook'' for hooks (with a default value which is a no-op,
%  below). Admittedly, the current implementation is a somewhat
%  simplistic and does vety little to catch errors, but it is intended
%  for developpers, after all. |\bbl@usehooks| is the commands used by
%  babel to execute hooks defined for an event.  
% \changes{babel~3.9k}{2014/03/23}{Removed a \cs{newcommand},
%    undefined in Plain}
%
%    \begin{macrocode}
\def\AddBabelHook#1#2{%
  \@ifundefined{bbl@hk@#1}{\EnableBabelHook{#1}}{}%
  \def\bbl@tempa##1,#2=##2,##3\@empty{\def\bbl@tempb{##2}}%
  \expandafter\bbl@tempa\bbl@evargs,#2=,\@empty
  \@ifundefined{bbl@ev@#1@#2}%
    {\bbl@csarg\bbl@add{ev@#2}{\bbl@elt{#1}}%
     \bbl@csarg\newcommand}%
    {\bbl@csarg\let{ev@#1@#2}\relax
     \bbl@csarg\newcommand}%
  {ev@#1@#2}[\bbl@tempb]}
\def\EnableBabelHook#1{\bbl@csarg\let{hk@#1}\@firstofone}
\def\DisableBabelHook#1{\bbl@csarg\let{hk@#1}\@gobble}
\def\bbl@usehooks#1#2{%
  \def\bbl@elt##1{%
    \@nameuse{bbl@hk@##1}{\@nameuse{bbl@ev@##1@#1}#2}}%
  \@nameuse{bbl@ev@#1}}
%    \end{macrocode}
%    To ensure forward compatibility, arguments in hooks are set
%    implicitly. So, if a further argument is added in the future,
%    there is no need to change the existing code. Note events
%    intended for \textsf{hyphen.cfg} are also loaded (just in
%    case you need them for some reason). 
%    \begin{macrocode}
\def\bbl@evargs{,% don't delete the comma
  everylanguage=1,loadkernel=1,loadpatterns=1,loadexceptions=1,%
  adddialect=2,patterns=2,defaultcommands=0,encodedcommands=2,write=0,%
  beforeextras=0,afterextras=0,stopcommands=0,stringprocess=0,%
  hyphenation=2,initiateactive=3,afterreset=0}
%    \end{macrocode}
%
% \begin{macro}{\babelensure}
%
% The user command just parses the optional argument and creates a
% new macro named |\bbl@ens@|\m{language}. We register a hook at the
% |afterextras| event which just executes this macro in a
% ``complete'' selection (which, if undefined, is |\relax| and does
% nothing). This part is somewhat involved because we have to make
% sure things are expanded the correct number of times.
%
% The macro |\bbl@ens@|\m{language} contains
% |\bbl@ensure|\marg{include}\marg{exclude}\marg{fontenc}, which
% in turn loops over the macros names in |\bbl@ensured|, excluding
% (with the help of |\in@|) those in the |exclude| list. If the
% |fontenc| is given (and not |\relax|), the |\fontencoding| is
% also added. Then we loop over the |include| list, but if the
% macro already contains |\foreignlanguage|, nothing is done.
% Note this macro (1) is not restricted to the preamble, and (2)
% changes are local.
%
% |\bbl@ensured| is the list of macros supposed to be ``ensured''.
% \changes{babel~3.9i}{2014/02/14}{Macro \cs{babelensure} added}
% \changes{babel~3.9k}{2014/03/23}{Encapsulate \cs{foreignlanguage} in
%   \cs{bbl@ensure@}language, to "protect" strings}
%
%    \begin{macrocode}
\newcommand\babelensure[2][]{%
  \AddBabelHook{babel-ensure}{afterextras}{%
    \ifcase\bbl@select@type
      \@nameuse{bbl@e@\languagename}%
    \fi}%
  \begingroup
    \let\bbl@ens@include\@empty
    \let\bbl@ens@exclude\@empty
    \def\bbl@ens@fontenc{\relax}%
    \def\bbl@tempb##1{%
      \ifx\@empty##1\else\noexpand##1\expandafter\bbl@tempb\fi}%
    \edef\bbl@tempa{\bbl@tempb#1\@empty}%
    \def\bbl@tempb##1=##2\@@{\@namedef{bbl@ens@##1}{##2}}%
    \bbl@for\bbl@tempa\bbl@tempa{\expandafter\bbl@tempb\bbl@tempa\@@}%
    \def\bbl@tempc{\bbl@ensure}%
    \expandafter\bbl@add\expandafter\bbl@tempc\expandafter{%
      \expandafter{\bbl@ens@include}}%
    \expandafter\bbl@add\expandafter\bbl@tempc\expandafter{%
      \expandafter{\bbl@ens@exclude}}%
    \toks@\expandafter{\bbl@tempc}%
    \edef\x{%
      \endgroup
      \noexpand\@namedef{bbl@e@#2}{\the\toks@{\bbl@ens@fontenc}}}%
    \x}
\def\bbl@ensure#1#2#3{%
  \def\bbl@tempb##1{% elt for \bbl@ensured list
    \ifx##1\@empty\else
      \in@{##1}{#2}%
      \ifin@\else
        \toks@\expandafter{##1}%
        \edef\bbl@tempa{%
          \noexpand\DeclareRobustCommand
          \bbl@csarg\noexpand{ensure@\languagename}[1]{%
            \noexpand\foreignlanguage{\languagename}%
            {\ifx\relax#3\else
              \noexpand\fontencoding{#3}\noexpand\selectfont
             \fi
             ########1}}}%
        \bbl@tempa
        \edef##1{%
           \bbl@csarg\noexpand{ensure@\languagename}%
           {\the\toks@}}
      \fi
      \expandafter\bbl@tempb
    \fi}%
  \expandafter\bbl@tempb\bbl@ensured\@empty
  \def\bbl@tempa##1{% elt for include list
    \ifx##1\@empty\else
      \bbl@csarg\in@{ensure@\languagename\expandafter}\expandafter{##1}%
      \ifin@\else
        \bbl@tempb##1\@empty
      \fi
      \expandafter\bbl@tempa
    \fi}%
  \bbl@tempa#1\@empty} 
\def\bbl@ensured{%
  \prefacename\refname\abstractname\bibname\chaptername\appendixname
  \contentsname\listfigurename\listtablename\indexname\figurename
  \tablename\partname\enclname\ccname\headtoname\pagename\seename
  \alsoname\proofname\glossaryname\today}   
%    \end{macrocode}
%    \end{macro}
%
%  \subsection{Setting up language files}
%
% \begin{macro}{\LdfInit}
%    The second version of |\LdfInit| macro takes two arguments. The first
%    argument is the name of the language that will be defined in the
%    language definition file; the second argument is either a control
%    sequence or a string from which a control sequence should be
%    constructed. The existence of the control sequence indicates that
%    the file has been processed before.
%
%    At the start of processing a language definition file we always
%    check the category code of the at-sign. We make sure that it is
%    a `letter' during the processing of the file. We also save its
%    name as the last called option, even if not loaded.
%
%    Another character that needs to have the correct category code
%    during processing of language definition files is the equals sign,
%    `=', because it is sometimes used in constructions with the
%    |\let| primitive. Therefore we store its current catcode and
%    restore it later on.
% \changes{babel~3.7o}{2003/11/26}{make sure the equals sign has its
%    default category code}
%
%    Now we check whether we should perhaps stop the processing of
%    this file. To do this we first need to check whether the second
%    argument that is passed to |\LdfInit| is a control sequence. We
%    do that by looking at the first token after passing |#2| through
%    |string|. When it is equal to |\@backslashchar| we are dealing
%    with a control sequence which we can compare with |\@undefined|.
%
% \changes{babel~3.9a}{2012/08/11}{\cs{ldf@quit} is not delayed any
%   more after \cs{fi} , since \cs{endinput} is not executed
%   immediately}
% \changes{babel~3.9g}{2012/08/11}{Preset the ``family'' of macros
%   \cs{Babel}...} 
%   If so, we call |\ldf@quit| to set the main language, restore the
%   category code of the @-sign and call |\endinput|
%
%    When |#2| was \emph{not} a control sequence we construct one and
%    compare it with |\relax|.
%
%    Finally we check |\originalTeX|.
%    \begin{macrocode}
\def\LdfInit#1#2{%
  \chardef\atcatcode=\catcode`\@
  \catcode`\@=11\relax
  \chardef\eqcatcode=\catcode`\=
  \catcode`\==12\relax
  \expandafter\if\expandafter\@backslashchar
                 \expandafter\@car\string#2\@nil
    \ifx#2\@undefined\else
      \ldf@quit{#1}%
    \fi
  \else
    \expandafter\ifx\csname#2\endcsname\relax\else
      \ldf@quit{#1}%
    \fi
  \fi
  \let\bbl@screset\@empty
  \let\BabelStrings\bbl@opt@strings
  \let\BabelOptions\@empty
  \let\BabelLanguages\relax
  \ifx\originalTeX\@undefined
    \let\originalTeX\@empty
  \else
    \originalTeX
  \fi}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\ldf@quit}
% \changes{babel~3.6a}{1996/10/29}{Macro added}
%    This macro interrupts the processing of a language definition file.
% \changes{babel~3.7o}{2003/11/26}{Also restore the category code of
%    the equals sign}
%    \begin{macrocode}
\def\ldf@quit#1{%
  \expandafter\main@language\expandafter{#1}%
  \catcode`\@=\atcatcode \let\atcatcode\relax
  \catcode`\==\eqcatcode \let\eqcatcode\relax
  \endinput}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\ldf@finish}
% \changes{babel~3.6a}{1996/10/16}{Macro added}
%    This macro takes one argument. It is the name of the language
%    that was defined in the language definition file.
%
%    We load the local configuration file if one is present, we set
%    the main language (taking into account that the argument might be
%    a control sequence that needs to be expanded) and reset the
%    category code of the @-sign.
% \changes{babel~3.7o}{2003/11/26}{Also restore the category code of
%    the equals sign}
% \changes{babel~3.9a}{2012/10/01}{Added \cs{bbl@afterlang} which
%    executes the code delayed with \cs{AfterBabelLanguage}}
%    \begin{macrocode}
\def\ldf@finish#1{%
  \loadlocalcfg{#1}%
  \bbl@afterlang
  \let\bbl@afterlang\relax
  \let\BabelModifiers\relax
  \let\bbl@screset\relax
  \expandafter\main@language\expandafter{#1}%
  \catcode`\@=\atcatcode \let\atcatcode\relax
  \catcode`\==\eqcatcode \let\eqcatcode\relax}
%    \end{macrocode}
%  \end{macro}
%
%    After the preamble of the document the commands |\LdfInit|,
%    |\ldf@quit| and |\ldf@finish| are no longer needed. Therefore
%    they are turned into warning messages in \LaTeX.
%    \begin{macrocode}
\@onlypreamble\LdfInit
\@onlypreamble\ldf@quit
\@onlypreamble\ldf@finish
%    \end{macrocode}
%
%  \begin{macro}{\main@language}
% \changes{babel~3.5a}{1995/02/17}{Macro added}
% \changes{babel~3.6a}{1996/10/16}{\cs{main@language} now also sets
%    \cs{languagename} and \cs{l@languagename} for use by other
%    packages in the preamble of a document}
%  \begin{macro}{\bbl@main@language}
% \changes{babel~3.5a}{1995/02/17}{Macro added}
%    This command should be used in the various language definition
%    files. It stores its argument in |\bbl@main@language|; to be used
%    to switch to the correct language at the beginning of the
%    document.
% \changes{babel~3.8l}{2008/07/06}{Use \cs{bbl@patterns}}
%    \begin{macrocode}
\def\main@language#1{%
  \def\bbl@main@language{#1}%
  \let\languagename\bbl@main@language
  \bbl@patterns{\languagename}}
%    \end{macrocode}
%
%    We also have to make sure that some code gets executed at the
%    beginning of the document.
%    \begin{macrocode}
\AtBeginDocument{%
  \expandafter\selectlanguage\expandafter{\bbl@main@language}}
%    \end{macrocode}
%  \end{macro}
%  \end{macro}
%
% \subsection{Shorthands}
%
%  \begin{macro}{\bbl@add@special}
% \changes{babel~3.2}{1991/11/10}{Added macro}
%    The macro |\bbl@add@special| is used to add a new character (or
%    single character control sequence) to the macro |\dospecials|
%    (and |\@sanitize| if \LaTeX\ is used).
%
%    To keep all changes local, we begin a new group.  Then we
%    redefine the macros |\do| and |\@makeother| to add themselves and
%    the given character without expansion.
%
%    To add the character to the macros, we expand the original macros
%    with the additional character inside the redefinition of the
%    macros.  Because |\@sanitize| can be undefined, we put the
%    definition inside a conditional.
%    \begin{macrocode}
\def\bbl@add@special#1{%
  \begingroup
    \def\do{\noexpand\do\noexpand}%
    \def\@makeother{\noexpand\@makeother\noexpand}%
  \edef\x{\endgroup
    \def\noexpand\dospecials{\dospecials\do#1}%
    \expandafter\ifx\csname @sanitize\endcsname\relax \else
      \def\noexpand\@sanitize{\@sanitize\@makeother#1}%
    \fi}%
  \x}
%    \end{macrocode}
%    The macro |\x| contains at this moment the following:\\
%    |\endgroup\def\dospecials{|\textit{old contents}%
%    |\do|\meta{char}|}|.\\
%    If |\@sanitize| is defined, it contains an additional definition
%    of this macro.  The last thing we have to do, is the expansion of
%    |\x|.  Then |\endgroup| is executed, which restores the old
%    meaning of |\x|, |\do| and |\@makeother|.  After the group is
%    closed, the new definition of |\dospecials| (and |\@sanitize|) is
%    assigned.
%
%  \end{macro}
%
%  \begin{macro}{\bbl@remove@special}
% \changes{babel~3.2}{1991/11/10}{Added macro}
%    The companion of the former macro is |\bbl@remove@special|.  It
%    is used to remove a character from the set macros |\dospecials|
%    and |\@sanitize|.
%
%    To keep all changes local, we begin a new group.  Then we define
%    a help macro |\x|, which expands to empty if the characters
%    match, otherwise it expands to its nonexpandable input.  Because
%    \TeX\ inserts a |\relax|, if the corresponding |\else| or |\fi|
%    is scanned before the comparison is evaluated, we provide a `stop
%    sign' which should expand to nothing.
%
%    With the help of this macro we define |\do| and |\make@other|.
%
%    The rest of the work is similar to |\bbl@add@special|.
%    \begin{macrocode}
\def\bbl@remove@special#1{%
  \begingroup
    \def\x##1##2{\ifnum`#1=`##2\noexpand\@empty
                 \else\noexpand##1\noexpand##2\fi}%
    \def\do{\x\do}%
    \def\@makeother{\x\@makeother}%
  \edef\x{\endgroup
    \def\noexpand\dospecials{\dospecials}%
    \expandafter\ifx\csname @sanitize\endcsname\relax \else
      \def\noexpand\@sanitize{\@sanitize}%
    \fi}%
  \x}
%    \end{macrocode}
%  \end{macro}
%
%
%  \begin{macro}{\initiate@active@char}
% \changes{babel~3.5a}{1995/02/11}{Added macro}
% \changes{babel~3.5b}{1995/03/03}{Renamed macro}
%    A language definition file can call this macro to make a
%    character active. This macro takes one argument, the character
%    that is to be made active. When the character was already active
%    this macro does nothing. Otherwise, this macro defines the
%    control sequence |\normal@char|\m{char} to expand to the
%    character in its `normal state' and it defines the active
%    character to expand to |\normal@char|\m{char} by default
%    (\m{char} being the character to be made active). Later its
%    definition can be changed to expand to |\active@char|\m{char}
%    by calling |\bbl@activate{|\m{char}|}|.
%
%    For example, to make the double quote character active one could
%    have |\initiate@active@char{"}| in a language definition file.
%    This defines |"| as |\active@prefix "\active@char"| (where the
%    first |"| is the character with its original catcode, when the
%    shorthand is created, and |\active@char"| is a single token). In
%    protected contexts, it expands to |\protect "| or |\noexpand "|
%    (ie, with the original |"|); otherwise |\active@char"| is
%    executed. This macro in turn expands to |\normal@char"| in
%    ``safe'' contexts (eg, |\label|), but |\user@active"| in normal
%    ``unsafe'' ones. The latter search a definition in the user,
%    language and system levels, in this order, but if none is found,
%    |\normal@char"| is used.  However, a deactivated shorthand (with
%    |\bbl@deactivate| is defined as |\active@prefix "\normal@char"|.
%
%    The following macro is used to define shorthands in the three
%    levels. It takes 4 arguments: the (string'ed) character,
%    |\<level>@group|, |<level>@active| and |<next-level>@active|
%    (except in |system|). 
% \changes{babel~3.9a}{2012/08/18}{New macro, with code from
%    \cs{@initiate@active@char}}
%    \begin{macrocode}
\def\bbl@active@def#1#2#3#4{%
  \@namedef{#3#1}{%
    \expandafter\ifx\csname#2@sh@#1@\endcsname\relax
      \bbl@afterelse\bbl@sh@select#2#1{#3@arg#1}{#4#1}%
    \else
      \bbl@afterfi\csname#2@sh@#1@\endcsname
    \fi}%
%    \end{macrocode}
%    When there is also no current-level shorthand with an argument we
%    will check whether there is a next-level  defined shorthand for
%    this active character. 
% \changes{babel~3.7e}{1999/09/24}{pass the argument on with braces in
%    order to prevent it from breaking up}
% \changes{babel~3.7f}{2000/02/18}{remove the braces again}
%    \begin{macrocode}
  \long\@namedef{#3@arg#1}##1{%
    \expandafter\ifx\csname#2@sh@#1@\string##1@\endcsname\relax
      \bbl@afterelse\csname#4#1\endcsname##1%
    \else
      \bbl@afterfi\csname#2@sh@#1@\string##1@\endcsname
    \fi}}%
%    \end{macrocode}
% \changes{babel~3.9a}{2012/08/18}{Removed an extra hash. Now calls
%    \cs{@initiate@active@char} with 3 arguments.}
%    |\initiate@active@char| calls |\@initiate@active@char| with 3
%    arguments. All of them are the same character with different
%    catcodes: active, other (string'ed) and the original one.
%    \begin{macrocode}
\def\initiate@active@char#1{%
  \expandafter\ifx\csname active@char\string#1\endcsname\relax
    \bbl@withactive
      {\expandafter\@initiate@active@char\expandafter}#1\string#1#1%
  \fi}
%    \end{macrocode}
% \changes{babel~3.9e}{2012/08/18}{Introduced the 3-argument
%   \cs{@initiate@active@char}, with different catcodes: active,
%   string'ed, and original. Reorganized}
% \changes{babel~3.9a}{2012/08/19}{The catcode is saved}
% \changes{babel~3.9a}{2012/09/09}{The original definition is saved,
% too}
% \changes{babel~3.9a}{2012/12/27}{Take into account mathematically
%   active chars, to avoid infinite loops}
%   The very first thing to do is saving the original catcode and the
%   original definition, even if not active, which is possible
%   (undefined characters require a special treatement to avoid
%   making them |\relax|).  
%    \begin{macrocode}
\def\@initiate@active@char#1#2#3{%
  \expandafter\edef\csname bbl@oricat@#2\endcsname{%
    \catcode`#2=\the\catcode`#2\relax}%
  \ifx#1\@undefined
    \expandafter\edef\csname bbl@oridef@#2\endcsname{%
      \let\noexpand#1\noexpand\@undefined}%
  \else
    \expandafter\let\csname bbl@oridef@@#2\endcsname#1%
    \expandafter\edef\csname bbl@oridef@#2\endcsname{%
      \let\noexpand#1%
      \expandafter\noexpand\csname bbl@oridef@@#2\endcsname}%
  \fi
%    \end{macrocode}
%    If the character is already active we provide the default
%    expansion under this shorthand mechanism. Otherwise we write a
%    message in the transcript file, and define |\normal@char|\m{char}
%    to expand to the character in its default state. If the character
%    is mathematically active when \babel{} is loaded (for example
%    |'|) the normal expansion is somewhat different to avoid an
%    infinite loop (but it does not prevent the loop if the mathcode
%    is set to |"8000| \textit{a posteriori}).
%    \begin{macrocode}
  \ifx#1#3\relax
    \expandafter\let\csname normal@char#2\endcsname#3%
  \else
    \bbl@info{Making #2 an active character}%
    \ifnum\mathcode`#2="8000
      \@namedef{normal@char#2}{%
        \textormath{#3}{\csname bbl@oridef@@#2\endcsname}}%
    \else
      \@namedef{normal@char#2}{#3}%
    \fi
%    \end{macrocode}
%    To prevent problems with the loading of other packages after
%    \babel\ we reset the catcode of the character to the original one
%    at the end of the package and of each language file (except with
%    \textsf{KeepShorthandsActive}). It is re-activate again at
%    |\begin{document}|.  We also need to make sure that the
%    shorthands are active during the processing of the \file{.aux}
%    file. Otherwise some citations may give unexpected results in
%    the printout when a shorthand was used in the optional argument
%    of |\bibitem| for example.
% \changes{babel~3.6i}{1997/03/01}{Make shorthands active during
%    \file{.aux} file processing}. Then we
%    make it active (not strictly necessary, but done for backward
%    compatibility).
% \changes{babel~3.5f}{1995/12/01}{Restore the category code of a
%    shorthand char at end of package}
% \changes{babel~3.6f}{1997/01/14}{Made restoring of the category code
%    of shorthand characters optional}
% \changes{babel~3.7a}{1997/03/21}{Use \cs{@ifpackagewith} to
%    determine whether shorthand characters need to remain active}
%    \begin{macrocode}
    \bbl@restoreactive{#2}%
    \AtBeginDocument{%
      \catcode`#2\active
      \if@filesw
        \immediate\write\@mainaux{\catcode`\string#2\active}%
      \fi}%
    \expandafter\bbl@add@special\csname#2\endcsname
    \catcode`#2\active
  \fi
%    \end{macrocode}
%    Now we have set |\normal@char|\m{char}, we must define
%    |\active@char|\m{char}, to be executed when the character is
%    activated.  We define the first level expansion of
%    |\active@char|\m{char} to check the status of the |@safe@actives|
%    flag. If it is set to true we expand to the `normal' version of
%    this character, otherwise we call |\user@active|\m{char} to start
%    the search of a definition in the user, language and system
%    levels (or eventually |normal@char|\m{char}).
% \changes{babel~3.9a}{2012/12/27}{Added code for option math=normal}
% \changes{babel~3.9i}{2014/02/03}{Don't call directly
%   \cs{user@active}, but with an intermediate step}
%    \begin{macrocode}
  \let\bbl@tempa\@firstoftwo
  \if\string^#2%
    \def\bbl@tempa{\noexpand\textormath}%
  \else
    \ifx\bbl@mathnormal\@undefined\else
      \let\bbl@tempa\bbl@mathnormal
    \fi
  \fi
  \expandafter\edef\csname active@char#2\endcsname{%
    \bbl@tempa
      {\noexpand\if@safe@actives
         \noexpand\expandafter
         \expandafter\noexpand\csname normal@char#2\endcsname
       \noexpand\else
         \noexpand\expandafter
         \expandafter\noexpand\csname bbl@doactive#2\endcsname
       \noexpand\fi}%
     {\expandafter\noexpand\csname normal@char#2\endcsname}}%
  \bbl@csarg\edef{doactive#2}{%
    \expandafter\noexpand\csname user@active#2\endcsname}%
%    \end{macrocode}
%
% \changes{babel~3.9a}{2012/12/27}{Shorthands are not defined
%    directly, but with a couple of intermediate macros}
% 
%    We now define the default values which the shorthand is set to
%    when activated or deactivated. It is set to the deactivated form
%    (globally), so that the character expands to
%    \begin{center}
%    |\active@prefix| \m{char} |\normal@char|\m{char}
%    \end{center}
%    (where |\active@char|\m{char} is \emph{one} control sequence!).
%
%    \begin{macrocode}
  \bbl@csarg\edef{active@#2}{%
    \noexpand\active@prefix\noexpand#1%
    \expandafter\noexpand\csname active@char#2\endcsname}%
  \bbl@csarg\edef{normal@#2}{%
    \noexpand\active@prefix\noexpand#1%
    \expandafter\noexpand\csname normal@char#2\endcsname}%
  \expandafter\let\expandafter#1\csname bbl@normal@#2\endcsname
%    \end{macrocode}
%    The next level of the code checks whether a user has defined a
%    shorthand for himself with this character. First we check for a
%    single character shorthand. If that doesn't exist we check for a
%    shorthand with an argument.
% \changes{babel~3.5d}{1995/07/02}{Skip the user-level active char
%    with argument if no shorthands with arguments were defined}
% \changes{babel~3.8b}{2004/04/19}{Now use \cs{bbl@sh@select}}
% \changes{babel~3.9a}{2012/08/18}{Instead of the ``copy-paste pattern''
%    a new macro is used}
%    \begin{macrocode}
  \bbl@active@def#2\user@group{user@active}{language@active}%
  \bbl@active@def#2\language@group{language@active}{system@active}%
  \bbl@active@def#2\system@group{system@active}{normal@char}%
%    \end{macrocode}
%    In order to do the right thing when a shorthand with an argument
%    is used by itself at the end of the line we provide a definition
%    for the case of an empty argument. For that case we let the
%    shorthand character expand to its non-active self. Also, When a
%    shorthand combination such as |''| ends up in a heading \TeX\
%    would see |\protect'\protect'|. To prevent this from happening a
%    couple of shorthand needs to be defined at user level.
% \changes{babel~3.7f}{1999/12/09}{Added an extra shorthand
%    combination on user level to catch an interfering \cs{protect}}
% \changes{babel~3.9a}{2012/8/18}{Use \cs{user@group}, as above,
%    instead of the hardwired \texttt{user}}
%    \begin{macrocode}
  \expandafter\edef\csname\user@group @sh@#2@@\endcsname
    {\expandafter\noexpand\csname normal@char#2\endcsname}%
  \expandafter\edef\csname\user@group @sh@#2@\string\protect@\endcsname
    {\expandafter\noexpand\csname user@active#2\endcsname}%
%    \end{macrocode}
%    Finally, a couple of special cases are taken care of.  (1) If we
%    are making the right quote (|'|) active we need to change |\pr@m@s| as
%    well.  Also, make sure that a single |'| in math mode `does the
%    right thing'.  (2) If we are using the caret (|^|) as a shorthand
%    character special care should be taken to make sure math still
%    works. Therefore an extra level of expansion is introduced with a
%    check for math mode on the upper level.
%
% \changes{babel~3.7f}{1999/12/18}{Insert a check for math mode in
%    the definition of \cs{normal@char'}}
% \changes{babel~3.7g}{2000/10/02}{use \cs{textormath} to get rid
%    of the \cs{fi} (PR 3266)}
% \changes{babel~3.7f}{1999/12/18}{The redefinition needs to take
%    place one level higher, \cs{prim@s} needs to be redefined.}
% \changes{babel~3.7f}{1999/12/18}{Introduced an extra
%    level of expansion in the definition of an active caret}
% \changes{babel~3.7f}{2000/09/25}{Make an exception for the active
%    caret which needs an extra level of expansion}
% \changes{babel~3.9a}{2012/09/11}{The output routine resets the quote
%   to \cs{active@math@prime}, so we redefine the latter with the new
%  ``normal'' value}
% \changes{babel~3.9a}{2012/06/20}{Added a couple of missing
%    comment characters (PR 4146)}
% \changes{babel~3.9a}{2012/07/29}{Use \cs{textormath} instead of
%    \cs{ifmath}}
% \changes{babel~3.9a}{2012/11/26}{Compare the char, irrespective of
%    its catcode.}
% \changes{babel~3.9a}{2012/12/27}{Removed the redeclaration of
%   \cs{normal@char'} because it is handled in a generic way above}
% \changes{babel~3.9a}{2012/12/29}{Removed the intermediate step of
%   \cs{bbl@act@caret} and moved above} 
% \changes{babel~3.9i}{2012/12/29}{Added the event \cs{initiateactive}} 
%    \begin{macrocode}
  \if\string'#2%
    \let\prim@s\bbl@prim@s
    \let\active@math@prime#1%
  \fi
  \bbl@usehooks{initiateactive}{{#1}{#2}{#3}}}
%    \end{macrocode}
%
%    The following package options control the behaviour of shorthands
%    in math mode.
%    \begin{macrocode}
%<<*More package options>>
\DeclareOption{math=active}{}
\DeclareOption{math=normal}{\def\bbl@mathnormal{\noexpand\textormath}}
%<</More package options>>
%    \end{macrocode}
%    Initiating a shorthand makes active the char. That is not
%    strictly necessary but it is still done for backward
%    compatibility. So we need to restore the original catcode at the
%    end of package \textit{and} and the end of the |ldf|.
%
% \changes{babel~3.9a}{2012/07/04}{Catcodes are also restored after
%    each language, to prevent incompatibilities. Use \cs{string} instead
%    of \cs{noexpand} and add \cs{relax}}
% \changes{babel~3.9a}{2012/10/18}{Catcodes are deactivated in a separate
%    macro, which is made no-op when babel exits}
%
%    \begin{macrocode}
\@ifpackagewith{babel}{KeepShorthandsActive}%
  {\let\bbl@restoreactive\@gobble}%
  {\def\bbl@restoreactive#1{%
     \edef\bbl@tempa{%
       \noexpand\AfterBabelLanguage\noexpand\CurrentOption
         {\catcode`#1=\the\catcode`#1\relax}%
       \noexpand\AtEndOfPackage{\catcode`#1=\the\catcode`#1\relax}}%
     \bbl@tempa}%
   \AtEndOfPackage{\let\bbl@restoreactive\@gobble}}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\bbl@sh@select}
%    This command helps the shorthand supporting macros to select how
%    to proceed. Note that this macro needs to be expandable as do all
%    the shorthand macros in order for them to work in expansion-only
%    environments such as the argument of |\hyphenation|.
%
%    This macro expects the name of a group of shorthands in its first
%    argument and a shorthand character in its second argument. It
%    will expand to either |\bbl@firstcs| or |\bbl@scndcs|. Hence two
%    more arguments need to follow it.
% \changes{babel~3.8b}{2004/04/19}{Added command}
% \changes{babel~3.9a}{2012/08/18}{Removed \cs{string}s, because the
%   char are already string'ed}
%    \begin{macrocode}
\def\bbl@sh@select#1#2{%
  \expandafter\ifx\csname#1@sh@#2@sel\endcsname\relax
    \bbl@afterelse\bbl@scndcs
  \else
    \bbl@afterfi\csname#1@sh@#2@sel\endcsname
  \fi}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\active@prefix}
%    The command |\active@prefix| which is used in the expansion of
%    active characters has a function similar to |\OT1-cmd| in that it
%    |\protect|s the active character whenever |\protect| is
%    \emph{not} |\@typeset@protect|.
% \changes{babel~3.5d}{1995/07/02}{\cs{@protected@cmd} has vanished
%    from \file{ltoutenc.dtx}}
% \changes{babel~3.7o}{2003/11/17}{Added handling of the situation
%    where \cs{protect} is set to \cs{@unexpandable@protect}}
%    \begin{macrocode}
\def\active@prefix#1{%
  \ifx\protect\@typeset@protect
  \else
%    \end{macrocode}
%    When |\protect| is set to |\@unexpandable@protect| we make sure
%    that the active character is als \emph{not} expanded by inserting
%    |\noexpand| in front of it. The |\@gobble| is needed to remove
%    a token such as |\activechar:| (when the double colon was the
%    active character to be dealt with).
%    \begin{macrocode}
    \ifx\protect\@unexpandable@protect
      \noexpand#1%
    \else
      \protect#1%
    \fi
    \expandafter\@gobble
  \fi}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\if@safe@actives}
%    In some circumstances it is necessary to be able to change the
%    expansion of an active character on the fly. For this purpose the
%    switch |@safe@actives| is available. The setting of this switch
%    should be checked in the first level expansion of
%    |\active@char|\m{char}.
%    \begin{macrocode}
\newif\if@safe@actives
\@safe@activesfalse
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\bbl@restore@actives}
% \changes{babel~3.7m}{2003/11/15}{New macro added}
%    When the output routine kicks in while the
%    active characters were made ``safe'' this must be undone in
%    the headers to prevent unexpected typeset results. For this
%    situation we define a command to make them ``unsafe'' again.
%    \begin{macrocode}
\def\bbl@restore@actives{\if@safe@actives\@safe@activesfalse\fi}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\bbl@activate}
%  \begin{macro}{\bbl@deactivate}
%  \changes{babel~3.5a}{1995/02/11}{Added macro}
%  \changes{babel~3.9a}{2013/01/11}{\cs{bbl@withactive} makes sure the
%    catcode is active} 
%    Both macros take one argument, like |\initiate@active@char|. The
%    macro is used to change the definition of an active character to
%    expand to |\active@char|\m{char} in the case of |\bbl@activate|,
%    or |\normal@char|\m{char} in the case of
%    |\bbl@deactivate|.
%    \begin{macrocode}
\def\bbl@activate#1{%
  \bbl@withactive{\expandafter\let\expandafter}#1%
    \csname bbl@active@\string#1\endcsname}
\def\bbl@deactivate#1{%
  \bbl@withactive{\expandafter\let\expandafter}#1%
    \csname bbl@normal@\string#1\endcsname}
%    \end{macrocode}
%  \end{macro}
%  \end{macro}
%
%  \begin{macro}{\bbl@firstcs}
%  \begin{macro}{\bbl@scndcs}
%    These macros have two arguments. They use one of their arguments
%    to build a control sequence from.
%    \begin{macrocode}
\def\bbl@firstcs#1#2{\csname#1\endcsname}
\def\bbl@scndcs#1#2{\csname#2\endcsname}
%    \end{macrocode}
%  \end{macro}
%  \end{macro}
%
%  \begin{macro}{\declare@shorthand}
%    The command |\declare@shorthand| is used to declare a shorthand
%    on a certain level. It takes three arguments:
%    \begin{enumerate}
%    \item a name for the collection of shorthands, i.e. `system', or
%      `dutch';
%    \item the character (sequence) that makes up the shorthand,
%      i.e. |~| or |"a|;
%    \item the code to be executed when the shorthand is encountered.
%    \end{enumerate}
% \changes{babel~3.5d}{1995/07/02}{Make a `note' when a shorthand with
%    an argument is defined.}
% \changes{babel~3.6i}{1997/02/23}{Make it possible to distinguish the
%    constructed control sequences for the case with argument}
% \changes{babel~3.8b}{2004/04/19}{We need to support shorthands with
%    and without argument in different groups; added the name of the
%    group to the storage macro}
% \changes{babel~3.9a}{2012/07/03}{Check if shorthands are redefined}
%    \begin{macrocode}
\def\declare@shorthand#1#2{\@decl@short{#1}#2\@nil}
\def\@decl@short#1#2#3\@nil#4{%
  \def\bbl@tempa{#3}%
  \ifx\bbl@tempa\@empty
    \expandafter\let\csname #1@sh@\string#2@sel\endcsname\bbl@scndcs
    \@ifundefined{#1@sh@\string#2@}{}%
      {\def\bbl@tempa{#4}%
       \expandafter\ifx\csname#1@sh@\string#2@\endcsname\bbl@tempa
       \else
         \bbl@info
           {Redefining #1 shorthand \string#2\\%
            in language \CurrentOption}%
       \fi}%
    \@namedef{#1@sh@\string#2@}{#4}%
  \else
    \expandafter\let\csname #1@sh@\string#2@sel\endcsname\bbl@firstcs
    \@ifundefined{#1@sh@\string#2@\string#3@}{}%
      {\def\bbl@tempa{#4}%
       \expandafter\ifx\csname#1@sh@\string#2@\string#3@\endcsname\bbl@tempa
       \else
         \bbl@info
           {Redefining #1 shorthand \string#2\string#3\\%
            in language \CurrentOption}%
       \fi}%
    \@namedef{#1@sh@\string#2@\string#3@}{#4}%
  \fi}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\textormath}
%    Some of the shorthands that will be declared by the language
%    definition files have to be usable in both text and mathmode. To
%    achieve this the helper macro |\textormath| is provided.
% \changes{babel~3.9a}{2012/12/29}{Failed if an argument had a
%    condicional. Use the more robust mechanism of \cs{XXXoftwo}} 
%    \begin{macrocode}
\def\textormath{%
  \ifmmode
    \expandafter\@secondoftwo
  \else
    \expandafter\@firstoftwo
  \fi}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\user@group}
%  \begin{macro}{\language@group}
%  \begin{macro}{\system@group}
%    The current concept of `shorthands' supports three levels or
%    groups of shorthands. For each level the name of the level or
%    group is stored in a macro. The default is to have a user group;
%    use language group `english' and have a system group called
%    `system'.
% \changes{babel~3.6i}{1997/02/24}{Have a user group called `user' by
%    default}
%    \begin{macrocode}
\def\user@group{user}
\def\language@group{english}
\def\system@group{system}
%    \end{macrocode}
%  \end{macro}
%  \end{macro}
%  \end{macro}
%
%  \begin{macro}{\useshorthands}
%    This is the user level command to tell \LaTeX\ that user level
%    shorthands will be used in the document. It takes one argument,
%    the character that starts a shorthand. First note that this is
%    user level, and then initialize and activate the character for
%    use as a shorthand character (ie, it's active in the
%    preamble). Languages can deactivate shorthands, so a starred
%    version is also provided which activates them always after the
%    language has been switched.
%
% \changes{babel~3.7j}{2001/11/11}{When \TeX\ has seen a character
%    its category code is fixed; need to use a `stand-in' for the
%    call of \cs{bbl@activate}} 
% \changes{babel~3.7j}{2003/09/11}{The change from 11/112001 was
%    incomplete}
% \changes{babel~3.9a}{2012/08/05}{Now \cs{bbl@activate} makes sure
%    the catcode is active, so this part is simplified}
% \changes{babel~3.9a}{2012/08/12}{User shorhands can be
%   defined even with shorthands=off}
%    \begin{macrocode}
\def\useshorthands{%
  \@ifstar\bbl@usesh@s{\bbl@usesh@x{}}}
\def\bbl@usesh@s#1{%
  \bbl@usesh@x
    {\AddBabelHook{babel-sh-\string#1}{afterextras}{\bbl@activate{#1}}}%
    {#1}}
\def\bbl@usesh@x#1#2{%
  \bbl@ifshorthand{#2}%
    {\def\user@group{user}%
     \initiate@active@char{#2}%
     #1%
     \bbl@activate{#2}}%
    {\bbl@error
       {Cannot declare a shorthand turned off (\string#2)}
       {Sorry, but you cannot use shorthands which have been\\%
        turned off in the package options}}}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\defineshorthand}
% \changes{babel~3.9a}{2012/08/05}{Added optional argument, to provide
%    a way to (re)define language shorthands} 
% \changes{babel~3.9a}{2012/08/25}{Extended for language-dependent
%    user macros, with two new auxiliary macros}
%    Currently we only support two groups of user level shorthands,
%    named internally |user| and |user@<lang>| (language-dependent
%    user shorthands). By default, only the first one is taken into
%    account, but if the former is also used (in the optional argument
%    of |\defineshorthand|) a new level is inserted for it
%    (|user@generic|, done by |\bbl@set@user@generic|); we make also
%    sure |{}| and |\protect| are taken into account in this new top
%    level.
%    \begin{macrocode}
\def\user@language@group{user@\language@group}
\def\bbl@set@user@generic#1#2{%
  \@ifundefined{user@generic@active#1}%
    {\bbl@active@def#1\user@language@group{user@active}{user@generic@active}%
     \bbl@active@def#1\user@group{user@generic@active}{language@active}%
     \expandafter\edef\csname#2@sh@#1@@\endcsname{%
       \expandafter\noexpand\csname normal@char#1\endcsname}%
     \expandafter\edef\csname#2@sh@#1@\string\protect@\endcsname{%
       \expandafter\noexpand\csname user@active#1\endcsname}}%
  \@empty}
\newcommand\defineshorthand[3][user]{%
  \edef\bbl@tempa{\zap@space#1 \@empty}%
  \bbl@for\bbl@tempb\bbl@tempa{%
    \if*\expandafter\@car\bbl@tempb\@nil
      \edef\bbl@tempb{user@\expandafter\@gobble\bbl@tempb}%
      \@expandtwoargs
        \bbl@set@user@generic{\expandafter\string\@car#2\@nil}\bbl@tempb
    \fi
    \declare@shorthand{\bbl@tempb}{#2}{#3}}}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\languageshorthands}
%    A user level command to change the language from which shorthands
%    are used. Unfortunately, \babel{} currently does not keep track
%    of defined groups, and therefore there is no way to catch a
%    possible change in casing.
%    \begin{macrocode}
\def\languageshorthands#1{\def\language@group{#1}}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\aliasshorthand}
% \changes{babel~3.5f}{1996/01/25}{New command}
%    First the new shorthand needs to be initialized,
%    \begin{macrocode}
\def\aliasshorthand#1#2{%
  \bbl@ifshorthand{#2}%
    {\expandafter\ifx\csname active@char\string#2\endcsname\relax
       \ifx\document\@notprerr
         \@notshorthand{#2}%
       \else
         \initiate@active@char{#2}%
%    \end{macrocode}
% \changes{babel~3.9a}{2012/08/06}{Instead of letting the new shorthand to
%    the original char, which very often didn't work, we define it
%    directly}
% \changes{babel~3.9a}{2012/08/20}{Make sure both characters (old an
%    new) are active}
%    Then, we define the new shorthand in terms of the original
%    one, but note with |\aliasshorthands{"}{/}| is
%    |\active@prefix /\active@char/|, so we still need to let the
%    lattest to |\active@char"|.
%    \begin{macrocode}
         \expandafter\let\csname active@char\string#2\expandafter\endcsname
           \csname active@char\string#1\endcsname
         \expandafter\let\csname normal@char\string#2\expandafter\endcsname
           \csname normal@char\string#1\endcsname
         \bbl@activate{#2}%
       \fi
     \fi}%
    {\bbl@error
       {Cannot declare a shorthand turned off (\string#2)}
       {Sorry, but you cannot use shorthands which have been\\%
        turned off in the package options}}}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\@notshorthand}
% \changes{v3.8d}{2004/11/20}{Error message added}
%    
%    \begin{macrocode}
\def\@notshorthand#1{%
  \bbl@error{%
    The character `\string #1' should be made a shorthand character;\\%
    add the command \string\useshorthands\string{#1\string} to
    the preamble.\\%
    I will ignore your instruction}%
   {You may proceed, but expect unexpected results}}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\shorthandon}
% \changes{babel~3.7a}{1998/06/07}{Added command}
%  \begin{macro}{\shorthandoff}
% \changes{babel~3.7a}{1998/06/07}{Added command}
% \changes{babel~3.9a}{2012/09/08}{Added code for the starred variant
%    of \cs{shorthandoff}} 
%    The first level definition of these macros just passes the
%    argument on to |\bbl@switch@sh|, adding |\@nil| at the end to
%    denote the end of the list of characters.
%    \begin{macrocode}
\newcommand*\shorthandon[1]{\bbl@switch@sh\@ne#1\@nnil}
\DeclareRobustCommand*\shorthandoff{%
  \@ifstar{\bbl@shorthandoff\tw@}{\bbl@shorthandoff\z@}}
\def\bbl@shorthandoff#1#2{\bbl@switch@sh#1#2\@nnil}
%    \end{macrocode}
%
%  \begin{macro}{\bbl@switch@sh}
% \changes{babel~3.7a}{1998/06/07}{Added command}
% \changes{babel~3.9a}{2013/02/21}{Code revised}
%    The macro |\bbl@switch@sh| takes the list of characters apart one
%    by  one and subsequently switches the category code of the
%    shorthand character according to the first argument of
%    |\bbl@switch@sh|.
%
%    But before any of this switching takes place we make sure that
%    the character we are dealing with is known as a shorthand
%    character. If it is, a macro such as |\active@char"| should
%    exist.
%
%    Switching off and on is easy -- we just set the category
%    code to `other' (12) and |\active|. With the starred version, the
%    original catcode and the original definition, saved
%    in |@initiate@active@char|, are restored. 
%
%    \begin{macrocode}
\def\bbl@switch@sh#1#2{%
  \ifx#2\@nnil\else
    \@ifundefined{bbl@active@\string#2}%
      {\bbl@error
         {I cannot switch `\string#2' on or off--not a shorthand}%
         {This character is not a shorthand. Maybe you made\\%
          a typing mistake? I will ignore your instruction}}%
      {\ifcase#1%
         \catcode`#212\relax
       \or
         \catcode`#2\active
       \or
         \csname bbl@oricat@\string#2\endcsname
         \csname bbl@oridef@\string#2\endcsname
       \fi}%
    \bbl@afterfi\bbl@switch@sh#1%
  \fi}
%    \end{macrocode}
%  \end{macro}
%  \end{macro}
%  \end{macro}
%
% \changes{babel~3.9a}{2012/06/16}{Added code}
%
% Note the value is that at the expansion time, eg, in the preample
% shorhands are usually deactivated.
%    \begin{macrocode}
\def\babelshorthand{\active@prefix\babelshorthand\bbl@putsh}
\def\bbl@putsh#1{%
  \@ifundefined{bbl@active@\string#1}%
     {\bbl@putsh@i#1\@empty\@nnil}%
     {\csname bbl@active@\string#1\endcsname}}
\def\bbl@putsh@i#1#2\@nnil{%
  \csname\languagename @sh@\string#1@%
    \ifx\@empty#2\else\string#2@\fi\endcsname}
\ifx\bbl@opt@shorthands\@nnil\else
  \let\bbl@s@initiate@active@char\initiate@active@char
  \def\initiate@active@char#1{%
    \bbl@ifshorthand{#1}{\bbl@s@initiate@active@char{#1}}{}}
  \let\bbl@s@switch@sh\bbl@switch@sh
  \def\bbl@switch@sh#1#2{%
    \ifx#2\@nnil\else
      \bbl@afterfi
      \bbl@ifshorthand{#2}{\bbl@s@switch@sh#1{#2}}{\bbl@switch@sh#1}%
    \fi}
  \let\bbl@s@activate\bbl@activate
  \def\bbl@activate#1{%
    \bbl@ifshorthand{#1}{\bbl@s@activate{#1}}{}}
  \let\bbl@s@deactivate\bbl@deactivate
  \def\bbl@deactivate#1{%
    \bbl@ifshorthand{#1}{\bbl@s@deactivate{#1}}{}}
\fi
%    \end{macrocode}
%
% \changes{babel~3.9a}{2012/12/27}{Removed redundant system declarations}
%
%  \begin{macro}{\bbl@prim@s}
% \changes{babel~3.7f}{1999/12/01}{Need to redefine \cs{prim@s} as
%    well as plain \TeX's definition uses \cs{next}}
%  \begin{macro}{\bbl@pr@m@s}
% \changes{babel~3.5a}{1995/03/10}{Added macro}
% \changes{babel~3.9a}{2012/07/29}{\cs{bbl@pr@m@s} rewritten to
%    take into account catcodes for both the quote and the hat}
%    One of the internal macros that are involved in substituting
%    |\prime| for each right quote in mathmode is |\prim@s|. This
%    checks if the next character is a right quote. When the right
%    quote is active, the definition of this macro needs to be adapted
%    to look also for an active right quote; the hat could be active,
%    too.
%    \begin{macrocode}
\def\bbl@prim@s{%
  \prime\futurelet\@let@token\bbl@pr@m@s}
\def\bbl@if@primes#1#2{%
  \ifx#1\@let@token
    \expandafter\@firstoftwo
  \else\ifx#2\@let@token
    \bbl@afterelse\expandafter\@firstoftwo
  \else
    \bbl@afterfi\expandafter\@secondoftwo
  \fi\fi}
\begingroup
  \catcode`\^=7  \catcode`\*=\active  \lccode`\*=`\^
  \catcode`\'=12 \catcode`\"=\active  \lccode`\"=`\' 
  \lowercase{%
    \gdef\bbl@pr@m@s{%
      \bbl@if@primes"'%
        \pr@@@s
        {\bbl@if@primes*^\pr@@@t\egroup}}}
\endgroup
%    \end{macrocode}
%  \end{macro}
%  \end{macro}
%
%    Usually the |~| is active and expands to \verb*=\penalty\@M\ =.
%    When it is written to the \file{.aux} file it is written
%    expanded. To prevent that and to be able to use the character |~|
%    as a start character for a shorthand, it is redefined here as a
%    one character shorthand on system level. The system declaration
%    is in most cases redundant (when |~| is still a non-break space),
%    and in some cases is inconvenient (if |~| has been redefined);
%    however, for backward compatibility it is maintained (some
%    existing documents may rely on the \babel{} value).
% \changes{babel~3.9i}{2014/02/06}{Moved from above, after
%    \cs{bbl@usehook} has been defined}
% \changes{babel~3.9k}{2014/02/06}{Moved again at the original place}
%    \begin{macrocode}
\initiate@active@char{~}
\declare@shorthand{system}{~}{\leavevmode\nobreak\ }
\bbl@activate{~}
%    \end{macrocode}
%
%  \begin{macro}{\OT1dqpos}
%  \begin{macro}{\T1dqpos}
%    The position of the double quote character is different for the
%    OT1 and T1 encodings. It will later be selected using the
%    |\f@encoding| macro. Therefore we define two macros here to store
%    the position of the character in these encodings.
%    \begin{macrocode}
\expandafter\def\csname OT1dqpos\endcsname{127}
\expandafter\def\csname T1dqpos\endcsname{4}
%    \end{macrocode}
%    When the macro |\f@encoding| is undefined (as it is in plain
%    \TeX) we define it here to expand to \texttt{OT1}
%    \begin{macrocode}
\ifx\f@encoding\@undefined
  \def\f@encoding{OT1}
\fi
%    \end{macrocode}
%  \end{macro}
%  \end{macro}
%
%  \subsection{Language attributes}
%
%    Language attributes provide a means to give the user control over
%    which features of the language definition files he wants to
%    enable.
% \changes{babel~3.7c}{1998/07/02}{Added support for language
%    attributes}
%  \begin{macro}{\languageattribute}
% \changes{babel~3.9a}{2012/09/07}{Use \cs{@expandtwoargs} with \cs{in@}}
%    The macro |\languageattribute| checks whether its arguments are
%    valid and then activates the selected language attribute.
%    First check whether the language is known, and then process each
%    attribute in the list.
%    \begin{macrocode}
\newcommand\languageattribute[2]{%
  \def\bbl@tempc{#1}%
  \bbl@fixname\bbl@tempc
  \bbl@iflanguage\bbl@tempc{%
    \bbl@loopx\bbl@attr{#2}{%
%    \end{macrocode}
%    We want to make sure that each attribute is selected only once;
%    therefore we store the already selected attributes in
%    |\bbl@known@attribs|. When that control sequence is not yet
%    defined this attribute is certainly not selected before.
%    \begin{macrocode}
      \ifx\bbl@known@attribs\@undefined
        \in@false
      \else
%    \end{macrocode}
%    Now we need to see if the attribute occurs in the list of
%    already selected attributes.
%    \begin{macrocode}
        \@expandtwoargs\in@{,\bbl@tempc-\bbl@attr,}{,\bbl@known@attribs,}%
      \fi
%    \end{macrocode}
%    When the attribute was in the list we issue a warning; this might
%    not be the users intention.
%    \begin{macrocode}
      \ifin@
        \bbl@warning{%
          You have more than once selected the attribute '\bbl@attr'\\%
          for language #1}%
      \else
%    \end{macrocode}
%    When we end up here the attribute is not selected before. So, we
%    add it to the list of selected attributes and execute the
%    associated \TeX-code.
%    \begin{macrocode}
        \edef\bbl@tempa{%
          \noexpand\bbl@add@list
          \noexpand\bbl@known@attribs{\bbl@tempc-\bbl@attr}}%
        \bbl@tempa
        \edef\bbl@tempa{\bbl@tempc-\bbl@attr}%
        \expandafter\bbl@ifknown@ttrib\expandafter{\bbl@tempa}\bbl@attributes%
        {\csname\bbl@tempc @attr@\bbl@attr\endcsname}%
        {\@attrerr{\bbl@tempc}{\bbl@attr}}%
     \fi}}}
%    \end{macrocode}
%    This command should only be used in the preamble of a document.
%    \begin{macrocode}
\@onlypreamble\languageattribute
%    \end{macrocode}
%    The error text to be issued when an unknown attribute is
%    selected.
%    \begin{macrocode}
\newcommand*{\@attrerr}[2]{%
  \bbl@error
    {The attribute #2 is unknown for language #1.}%
    {Your command will be ignored, type <return> to proceed}}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\bbl@declare@ttribute}
%    This command adds the new language/attribute combination to the
%    list of known attributes.
%
%    Then it defines a control sequence to be executed when the
%    attribute is used in a document. The result of this should be
%    that the macro |\extras...| for the current language is extended,
%    otherwise the attribute will not work as its code is removed from
%    memory at |\begin{document}|.
%    \begin{macrocode}
\def\bbl@declare@ttribute#1#2#3{%
  \@expandtwoargs\in@{,#2,}{,\BabelModifiers,}%
  \ifin@
    \AfterBabelLanguage{#1}{\languageattribute{#1}{#2}}%
  \fi
  \bbl@add@list\bbl@attributes{#1-#2}%
  \expandafter\def\csname#1@attr@#2\endcsname{#3}}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\bbl@ifattributeset}
% \changes{babel~3.7f}{2000/02/12}{macro added}
%    This internal macro has 4 arguments. It can be used to interpret
%    \TeX\ code based on whether a certain attribute was set. This
%    command should appear inside the argument to |\AtBeginDocument|
%    because the attributes are set in the document preamble,
%    \emph{after} \babel\ is loaded.
%
%    The first argument is the language, the second argument the
%    attribute being checked, and the third and fourth arguments are
%    the true and false clauses.
%    \begin{macrocode}
\def\bbl@ifattributeset#1#2#3#4{%
%    \end{macrocode}
%    First we need to find out if any attributes were set; if not
%    we're done.
%    \begin{macrocode}
  \ifx\bbl@known@attribs\@undefined
    \in@false
  \else
%    \end{macrocode}
%    The we need to check the list of known attributes.
%    \begin{macrocode}
    \@expandtwoargs\in@{,#1-#2,}{,\bbl@known@attribs,}%
  \fi
%    \end{macrocode}
%    When we're this far |\ifin@| has a value indicating if the
%    attribute in question was set or not. Just to be safe the code to
%    be executed is `thrown over the |\fi|'.
%    \begin{macrocode}
  \ifin@
    \bbl@afterelse#3%
  \else
    \bbl@afterfi#4%
  \fi
  }
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\bbl@add@list}
%    This internal macro adds its second argument to a comma
%    separated list in its first argument. When the list is not
%    defined yet (or empty), it will be initiated
%    \begin{macrocode}
\def\bbl@add@list#1#2{%
  \ifx#1\@undefined
    \def#1{#2}%
  \else
    \ifx#1\@empty
      \def#1{#2}%
    \else
      \edef#1{#1,#2}%
    \fi
  \fi
  }
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\bbl@ifknown@ttrib}
%    An internal macro to check whether a given language/attribute is
%    known. The macro takes 4 arguments, the language/attribute, the
%    attribute list, the \TeX-code to be executed when the attribute
%    is known and the \TeX-code to be executed otherwise.
%    \begin{macrocode}
\def\bbl@ifknown@ttrib#1#2{%
%    \end{macrocode}
%    We first assume the attribute is unknown.
%    \begin{macrocode}
  \let\bbl@tempa\@secondoftwo
%    \end{macrocode}
%    Then we loop over the list of known attributes, trying to find a
%    match.
%    \begin{macrocode}
  \bbl@loopx\bbl@tempb{#2}{%
    \expandafter\in@\expandafter{\expandafter,\bbl@tempb,}{,#1,}%
    \ifin@
%    \end{macrocode}
%    When a match is found the definition of |\bbl@tempa| is changed.
%    \begin{macrocode}
      \let\bbl@tempa\@firstoftwo
    \else
    \fi}%
%    \end{macrocode}
%    Finally we execute |\bbl@tempa|.
%    \begin{macrocode}
  \bbl@tempa
}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\bbl@clear@ttribs}
%    This macro removes all the attribute code from \LaTeX's memory at
%    |\begin{document}| time (if any is present).
% \changes{babel~3.7e}{1999/09/24}{When \cs{bbl@attributes} is
%    undefined this should be a no-op} 
%    \begin{macrocode}
\def\bbl@clear@ttribs{%
  \ifx\bbl@attributes\@undefined\else
    \bbl@loopx\bbl@tempa{\bbl@attributes}{%
      \expandafter\bbl@clear@ttrib\bbl@tempa.
      }%
    \let\bbl@attributes\@undefined
  \fi
  }
\def\bbl@clear@ttrib#1-#2.{%
  \expandafter\let\csname#1@attr@#2\endcsname\@undefined}
\AtBeginDocument{\bbl@clear@ttribs}
%    \end{macrocode}
%  \end{macro}
%
%  \subsection{Support for saving macro definitions}
%
%  To save the meaning of control sequences using |\babel@save|, we
%  use temporary control sequences.  To save hash table entries for
%  these control sequences, we don't use the name of the control
%  sequence to be saved to construct the temporary name.  Instead we
%  simply use the value of a counter, which is reset to zero each time
%  we begin to save new values.  This works well because we release
%  the saved meanings before we begin to save a new set of control
%  sequence meanings (see |\selectlanguage| and |\originalTeX|). Note
%  undefined macros are not undefined any more when saved -- they are
%  |\relax|'ed.
%
%  \begin{macro}{\babel@savecnt}
% \changes{babel~3.2}{1991/11/10}{Added macro}
%  \begin{macro}{\babel@beginsave}
% \changes{babel~3.2}{1991/11/10}{Added macro}
%    The initialization of a new save cycle: reset the counter to
%    zero.
%    \begin{macrocode}
\def\babel@beginsave{\babel@savecnt\z@}
%    \end{macrocode}
%    Before it's forgotten, allocate the counter and initialize all.
%    \begin{macrocode}
\newcount\babel@savecnt
\babel@beginsave
%    \end{macrocode}
%  \end{macro}
%  \end{macro}
%
%  \begin{macro}{\babel@save}
% \changes{babel~3.2}{1991/11/10}{Added macro}
%    The macro |\babel@save|\meta{csname} saves the current meaning of
%    the control sequence \meta{csname} to
%    |\originalTeX|\footnote{\cs{originalTeX} has to be
%    expandable, i.\,e.\ you shouldn't let it to \cs{relax}.}.
%    To do this, we let the current meaning to a temporary control
%    sequence, the restore commands are appended to |\originalTeX| and
%    the counter is incremented.
% \changes{babel~3.2c}{1992/03/17}{missing backslash led to errors
%    when executing \cs{originalTeX}}
% \changes{babel~3.2d}{1992/07/02}{saving in \cs{babel@i} and
%    restoring from \cs{@babel@i} doesn't work very well...}
%    \begin{macrocode}
\def\babel@save#1{%
  \expandafter\let\csname babel@\number\babel@savecnt\endcsname#1\relax
  \begingroup
    \toks@\expandafter{\originalTeX\let#1=}%
    \edef\x{\endgroup
      \def\noexpand\originalTeX{\the\toks@ \expandafter\noexpand
         \csname babel@\number\babel@savecnt\endcsname\relax}}%
  \x
  \advance\babel@savecnt\@ne}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\babel@savevariable}
% \changes{babel~3.2}{1991/11/10}{Added macro}
%    The macro |\babel@savevariable|\meta{variable} saves the value of
%    the variable.  \meta{variable} can be anything allowed after the
%    |\the| primitive.
%    \begin{macrocode}
\def\babel@savevariable#1{\begingroup
    \toks@\expandafter{\originalTeX #1=}%
    \edef\x{\endgroup
      \def\noexpand\originalTeX{\the\toks@ \the#1\relax}}%
  \x}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\bbl@frenchspacing}
%  \begin{macro}{\bbl@nonfrenchspacing}
%    Some languages need to have |\frenchspacing| in effect. Others
%    don't want that. The command |\bbl@frenchspacing| switches it on
%    when it isn't already in effect and |\bbl@nonfrenchspacing|
%    switches it off if necessary.
%    \begin{macrocode}
\def\bbl@frenchspacing{%
  \ifnum\the\sfcode`\.=\@m
    \let\bbl@nonfrenchspacing\relax
  \else
    \frenchspacing
    \let\bbl@nonfrenchspacing\nonfrenchspacing
  \fi}
\let\bbl@nonfrenchspacing\nonfrenchspacing
%    \end{macrocode}
%  \end{macro}
%  \end{macro}
%
% \subsection{Short tags}
%
% \begin{macro}{\babeltags}
% This macro is straightforward. After zapping spaces, we
% loop over the list and define the macros |\text|\m{tag} and
% |\|\m{tag}. Definitions are first expanded so that they don't
% contain |\csname| but the actual macro. 
% \changes{babel~3.9i}{2014/02/21}{Macro \cs{babeltags} added}
%
%   \begin{macrocode}
\def\babeltags#1{%
  \edef\bbl@tempa{\zap@space#1 \@empty}%
  \def\bbl@tempb##1=##2\@@{%
    \edef\bbl@tempc{%
      \noexpand\newcommand
      \expandafter\noexpand\csname ##1\endcsname{%
        \noexpand\protect
        \expandafter\noexpand\csname otherlanguage*\endcsname{##2}}
      \noexpand\newcommand
      \expandafter\noexpand\csname text##1\endcsname{%
        \noexpand\foreignlanguage{##2}}}
    \bbl@tempc}%
  \bbl@for\bbl@tempa\bbl@tempa{%
    \expandafter\bbl@tempb\bbl@tempa\@@}}
%    \end{macrocode}
% \end{macro}
%
%   \subsection{Hyphens}
%
%  \begin{macro}{\babelhyphenation}
%
%     This macro saves hyphenation exceptions. Two macros are used to
%     store them: |\bbl@hyphenation@| for the global ones and
%     |\bbl@hyphenation<lang>| for language ones. See |\bbl@patterns|
%     above for further details. We make sure there is a space between
%     words when multiple commands are used.
%     \changes{babel~3.9a}{2012/08/28}{Macro added}
%
%    \begin{macrocode}
\@onlypreamble\babelhyphenation
\AtEndOfPackage{%
  \newcommand\babelhyphenation[2][\@empty]{%
    \ifx\bbl@hyphenation@\relax
      \let\bbl@hyphenation@\@empty
    \fi
    \ifx\bbl@hyphlist\@empty\else
      \bbl@warning{%
        You must not intermingle \string\selectlanguage\space and\\%
        \string\babelhyphenation\space or some exception will not\\%
        be taken into account. Reported}%
    \fi
    \ifx\@empty#1%
      \protected@edef\bbl@hyphenation@{\bbl@hyphenation@\space#2}%
    \else
      \edef\bbl@tempb{\zap@space#1 \@empty}%
      \bbl@for\bbl@tempa\bbl@tempb{%
        \bbl@fixname\bbl@tempa
        \bbl@iflanguage\bbl@tempa{%
          \bbl@csarg\protected@edef{hyphenation@\bbl@tempa}{%
            \@ifundefined{bbl@hyphenation@\bbl@tempa}%
              \@empty
              {\csname bbl@hyphenation@\bbl@tempa\endcsname\space}%
            #2}}}%
    \fi}}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\bbl@allowhyphens}
% \changes{babel~3.2b}{1992/02/16}{Moved macro from language
%    definition files}
% \changes{babel~3.7a}{1998/03/12}{Make \cs{allowhyphens} a no-op for
%    T1 fontencoding}
% \changes{babel-3.9a}{2012/07/28}{Replaced many \cs{allowhyphens} by
%    \cs{bbl@allowhyphen}. They were either no-op or executed always.}
% \changes{babel-3.9i}{2014/01/29}{\cs{bbl@allowhyphens} must be
%    ignored at the beginning of a paragraph or table cell.}
%    This macro makes hyphenation possible. Basically its definition
%    is nothing more than |\nobreak| |\hskip| \texttt{0pt plus
%    0pt}\footnote{\TeX\ begins and ends a word for hyphenation at a
%    glue node. The penalty prevents a linebreak at this glue node.}.
%    \begin{macrocode}
\def\bbl@allowhyphens{\ifvmode\else\nobreak\hskip\z@skip\fi}
\def\bbl@t@one{T1}
\def\allowhyphens{\ifx\cf@encoding\bbl@t@one\else\bbl@allowhyphens\fi}
%    \end{macrocode}
%  \end{macro}
%
% \changes{babel-3.9a}{2012/08/27}{Added \cs{babelhyphen} and related
%    macros}
% \begin{macro}{\babelhyphen}
%    Macros to insert common hyphens. Note the space before |@| in
%    |\babelhyphen|. Instead of protecting it with
%    |\DeclareRobustCommand|, which could insert a |\relax|, we use
%    the same procedure as shorthands.
%    \begin{macrocode}
\newcommand\babelnullhyphen{\char\hyphenchar\font}
\def\babelhyphen{\active@prefix\babelhyphen\bbl@hyphen}
\def\bbl@hyphen{%
  \@ifstar{\bbl@hyphen@i @}{\bbl@hyphen@i\@empty}}
\def\bbl@hyphen@i#1#2{%
  \@ifundefined{bbl@hy@#1#2\@empty}%
    {\csname bbl@#1usehyphen\endcsname{\discretionary{#2}{}{#2}}}%
    {\csname bbl@hy@#1#2\@empty\endcsname}}
%    \end{macrocode}
%    The following two commands are used to wrap the ``hyphen'' and
%    set the behaviour of the rest of the word -- the version with a
%    single |@| is used when further hyphenation is allowed, while
%    that with |@@| if no more hyphen are allowed. In both cases, if
%    the hyphen is preceded by a positive space, breaking after the
%    hyphen is disallowed.
%
%    There should not be a discretionaty after a hyphen at the
%    beginning of a word, so it is prevented if preceded by a
%    skip. Unfortunately, this does handle cases like ``(-suffix)''.
%    |\nobreak| is always preceded by |\leavevmode|, in case the
%    shorthand starts a paragraph.
%    \begin{macrocode}
\def\bbl@usehyphen#1{%
  \leavevmode
  \ifdim\lastskip>\z@\mbox{#1}\nobreak\else\nobreak#1\fi
  \hskip\z@skip}
\def\bbl@@usehyphen#1{%
  \leavevmode\ifdim\lastskip>\z@\mbox{#1}\else#1\fi}
%    \end{macrocode}
%    The following macro inserts the hyphen char.
%    \begin{macrocode}
\def\bbl@hyphenchar{%
  \ifnum\hyphenchar\font=\m@ne
    \babelnullhyphen
  \else
    \char\hyphenchar\font
  \fi}
%    \end{macrocode}
%    Finally, we define the hyphen ``types''. Their names will not
%    change, so you may use them in |ldf|'s.
%    \begin{macrocode}
\def\bbl@hy@soft{\bbl@usehyphen{\discretionary{\bbl@hyphenchar}{}{}}}
\def\bbl@hy@@soft{\bbl@@usehyphen{\discretionary{\bbl@hyphenchar}{}{}}}
\def\bbl@hy@hard{\bbl@usehyphen\bbl@hyphenchar}
\def\bbl@hy@@hard{\bbl@@usehyphen\bbl@hyphenchar}
\def\bbl@hy@nobreak{\bbl@usehyphen{\mbox{\bbl@hyphenchar}\nobreak}}
\def\bbl@hy@@nobreak{\mbox{\bbl@hyphenchar}}
\def\bbl@hy@repeat{%
  \bbl@usehyphen{%
    \discretionary{\bbl@hyphenchar}{\bbl@hyphenchar}{\bbl@hyphenchar}%
    \nobreak}}
\def\bbl@hy@@repeat{%
  \bbl@@usehyphen{%
    \discretionary{\bbl@hyphenchar}{\bbl@hyphenchar}{\bbl@hyphenchar}}}
\def\bbl@hy@empty{\hskip\z@skip}
\def\bbl@hy@@empty{\discretionary{}{}{}}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\bbl@disc}
% \changes{babel~3.5f}{1996/01/24}{Macro moved from language
%    definition files}
%    For some languages the macro |\bbl@disc| is used to ease the
%    insertion of discretionaries for letters that behave `abnormally'
%    at a breakpoint.
%    \begin{macrocode}
\def\bbl@disc#1#2{\nobreak\discretionary{#2-}{}{#1}\bbl@allowhyphens}
%    \end{macrocode}
%  \end{macro}
%  \subsection{Multiencoding strings}
%
% \changes{babel~3.9a}{2012/09/05}{Added tentative code for string
%  declarations}
% \changes{babel~3.9a}{2012/12/24}{Added hooks}
%
% The aim following commands is to provide a commom interface for
% strings in several encodings. They also contains several hooks which
% can be ued by \luatex{} and \xetex. The code is organized here with
% pseudo-guards, so we start with the basic commands.
%
%  \paragraph{Tools}
%
% But first, a couple of tools. The first one makes global a local
% variable. This is not the best solution, but it works.
%    \begin{macrocode}
\def\bbl@toglobal#1{\global\let#1#1}
\def\bbl@recatcode#1{%
  \@tempcnta="7F
  \def\bbl@tempa{%
    \ifnum\@tempcnta>"FF\else
      \catcode\@tempcnta=#1\relax
      \advance\@tempcnta\@ne
      \expandafter\bbl@tempa
    \fi}%
  \bbl@tempa}
%    \end{macrocode}
%
% The second one. We need to patch |\@uclclist|, but it is done once
% and only if |\SetCase| is used or if strings are encoded.  The code
% is far from satisfactory for several reasons, including the fact
% |\@uclclist| is not a list any more. Therefore a package option is
% added to ignore it. Instead of gobbling the macro
% getting the next two elements (usually |\reserved@a|), we pass it as
% argument to |\bbl@uclc|. The parser is restarted inside
% |\|\m{lang}|@bbl@uclc| because we do not know how many expansions
% are necessary (depends on whether strings are encoded). The last
% part is tricky -- when uppercasing, we have:
% \begin{verbatim}
% \let\bbl@tolower\@empty\bbl@toupper\@empty
% \end{verbatim}
% and starts over (and similarly when lowercasing).
%    \changes{babel~3.9l}{2014/07/29}{Now tries to catch the parsing
%    macro. Removed some redundant code. Option |nocase|.}
%    \begin{macrocode}
\@ifpackagewith{babel}{nocase}%
  {\let\bbl@patchuclc\relax}%
  {\def\bbl@patchuclc{%
    \global\let\bbl@patchuclc\relax
    \g@addto@macro\@uclclist{\reserved@b{\reserved@b\bbl@uclc}}%
    \gdef\bbl@uclc##1{%
      \let\bbl@encoded\bbl@encoded@uclc
      \@ifundefined{\languagename @bbl@uclc}% and resumes it
        {##1}%
        {\let\bbl@tempa##1\relax % Used by LANG@bbl@uclc
         \csname\languagename @bbl@uclc\endcsname}%
      {\bbl@tolower\@empty}{\bbl@toupper\@empty}}%
    \gdef\bbl@tolower{\csname\languagename @bbl@lc\endcsname}%
    \gdef\bbl@toupper{\csname\languagename @bbl@uc\endcsname}}}
%    \end{macrocode}
%
%    \begin{macrocode}
%<<*More package options>>
\DeclareOption{nocase}{}
%<</More package options>>
%    \end{macrocode}
%
% The following package options control the behaviour of |\SetString|.
%
%    \begin{macrocode}
%<<*More package options>>
\let\bbl@opt@strings\@nnil % accept strings=value
\DeclareOption{strings}{\def\bbl@opt@strings{\BabelStringsDefault}}
\DeclareOption{strings=encoded}{\let\bbl@opt@strings\relax}
\def\BabelStringsDefault{generic}
%<</More package options>>
%    \end{macrocode}
%
%    \paragraph{Main command} This is the main command.  With the
%    first use it is redefined to omit the basic setup in subsequent
%    blocks. We make sure strings contain actual letters in the range
%    128-255, not active characters.
%    \changes{babel~3.9g}{2013/07/29}{Added starred variant. A bit of
%    clean up. Removed \cs{UseString}, which didn't work.}
%    \changes{babel~3.9g}{2013/08/01}{Now several languages can be
%    processed with \cs{BabelLanguages}, if set in the ldf.}
%    \begin{macrocode}
\@onlypreamble\StartBabelCommands
\def\StartBabelCommands{%
  \begingroup   
  \bbl@recatcode{11}%
  <@Macros local to BabelCommands@>
  \def\bbl@provstring##1##2{%
    \providecommand##1{##2}%
    \bbl@toglobal##1}%
  \global\let\bbl@scafter\@empty
  \let\StartBabelCommands\bbl@startcmds
  \ifx\BabelLanguages\relax
     \let\BabelLanguages\CurrentOption
  \fi
  \begingroup
  \let\bbl@screset\@nnil % local flag - disable 1st stopcommands
  \StartBabelCommands}
\def\bbl@startcmds{%
  \ifx\bbl@screset\@nnil\else
    \bbl@usehooks{stopcommands}{}%
  \fi
  \endgroup
  \begingroup
  \@ifstar
    {\ifx\bbl@opt@strings\@nnil
       \let\bbl@opt@strings\BabelStringsDefault
     \fi
     \bbl@startcmds@i}%
    \bbl@startcmds@i}
\def\bbl@startcmds@i#1#2{%
  \edef\bbl@L{\zap@space#1 \@empty}%
  \edef\bbl@G{\zap@space#2 \@empty}%
  \bbl@startcmds@ii}
%    \end{macrocode}
%    Parse the encoding info to get the label, input, and font parts.
%
%    Select the behaviour of |\SetString|. Thre are two main cases,
%    depending of if there is an optional argument: without it and
%    |strings=encoded|, strings are defined
%    always; otherwise, they are set only if they are still undefined
%    (ie, fallback values). With labelled blocks and
%    |strings=encoded|, define the strings, but with another value,
%    define strings only if the current label or font encoding is the
%    value of |strings|; otherwise (ie, no |strings| or a block whose
%    label is not in |strings=|) do nothing.
%
%    We presume the current block is not loaded, and therefore set
%    (above) a couple of default values to gobble the arguments. Then,
%    these macros are redefined if necessary according to several
%    parameters.
% \changes{babel~3.9g}{2013/08/04}{Use \cs{ProvideTextCommand}, which
%   does with encoded strings what the manual says.}
% \changes{babel~3.9h}{2013/11/08}{Tidied up code related to
%  \cs{bbl@scswitch}}
% 
%    \begin{macrocode}
\newcommand\bbl@startcmds@ii[1][\@empty]{%
  \let\SetString\@gobbletwo
  \let\bbl@stringdef\@gobbletwo
  \let\AfterBabelCommands\@gobble
  \ifx\@empty#1%
    \def\bbl@sc@label{generic}%
    \def\bbl@encstring##1##2{%
      \ProvideTextCommandDefault##1{##2}%
      \bbl@toglobal##1%
      \expandafter\bbl@toglobal\csname\string?\string##1\endcsname}%
    \let\bbl@sctest\in@true
  \else
    \let\bbl@sc@charset\space % <- zapped below
    \let\bbl@sc@fontenc\space % <-   "      "
    \def\bbl@tempa##1=##2\@nil{%
      \bbl@csarg\edef{sc@\zap@space##1 \@empty}{##2 }}%
    \bbl@for\bbl@tempb{label=#1}{\expandafter\bbl@tempa\bbl@tempb\@nil}%
    \def\bbl@tempa##1 ##2{% space -> comma
      ##1%
      \ifx\@empty##2\else\ifx,##1,\else,\fi\bbl@afterfi\bbl@tempa##2\fi}%
    \edef\bbl@sc@fontenc{\expandafter\bbl@tempa\bbl@sc@fontenc\@empty}%
    \edef\bbl@sc@label{\expandafter\zap@space\bbl@sc@label\@empty}%
    \edef\bbl@sc@charset{\expandafter\zap@space\bbl@sc@charset\@empty}%
    \def\bbl@encstring##1##2{%
      \bbl@for\bbl@tempc\bbl@sc@fontenc{%
        \@ifundefined{T@\bbl@tempc}%
          {}%
          {\ProvideTextCommand##1\bbl@tempc{##2}%
           \bbl@toglobal##1%
           \expandafter
           \bbl@toglobal\csname\bbl@tempc\string##1\endcsname}}}%
    \def\bbl@sctest{%
      \@expandtwoargs
      \in@{,\bbl@opt@strings,}{,\bbl@sc@label,\bbl@sc@fontenc,}}%
  \fi
  \ifx\bbl@opt@strings\@nnil         % ie, no strings key -> defaults
  \else\ifx\bbl@opt@strings\relax    % ie, strings=encoded
    \let\AfterBabelCommands\bbl@aftercmds
    \let\SetString\bbl@setstring
    \let\bbl@stringdef\bbl@encstring
  \else       % ie, strings=value
  \bbl@sctest
  \ifin@
    \let\AfterBabelCommands\bbl@aftercmds
    \let\SetString\bbl@setstring
    \let\bbl@stringdef\bbl@provstring
  \fi\fi\fi
  \bbl@scswitch
  \ifx\bbl@G\@empty
    \def\SetString##1##2{%
      \bbl@error{Missing group for string \string##1}%
        {You must assign strings to some category, typically\\%
         captions or extras, but you set none}}%
  \fi
  \ifx\@empty#1%
    \@expandtwoargs
    \bbl@usehooks{defaultcommands}{}%
  \else
    \@expandtwoargs
    \bbl@usehooks{encodedcommands}{{\bbl@sc@charset}{\bbl@sc@fontenc}}%
  \fi}
%    \end{macrocode}
%
%    There are two versions of |\bbl@scswitch|. The first version is
%    used when |ldf|s are read, and it makes sure
%    |\|\m{group}\m{language} is reset, but only once (|\bbl@screset|
%    is used to keep track of this). The second version is used in the
%    preamble and packages loaded after \babel{} and does nothing. The
%    macro |\bbl@forlang| loops |\bbl@L| but its body is executed only
%    if the value is in |\BabelLanguages| (inside \babel) or
%    |\date|\m{language} is defined (after \babel{} has been loaded).
%    There are also two version of |\bbl@forlang|. The first one skips
%    the current iteration if the language is not in |\BabelLanguages|
%    (used in |ldf|s), and the second one skips undefined languages
%    (after \babel{} has been loaded) . 
%
%   \begin{macrocode}
\def\bbl@forlang#1#2{%
  \bbl@for#1\bbl@L{%
    \@expandtwoargs\in@{,#1,}{,\BabelLanguages,}%
    \ifin@#2\relax\fi}}
\def\bbl@scswitch{%
  \bbl@forlang\bbl@tempa{%
    \ifx\bbl@G\@empty\else
      \ifx\SetString\@gobbletwo\else
        \edef\bbl@GL{\bbl@G\bbl@tempa}%
        \@expandtwoargs\in@{,\bbl@GL,}{,\bbl@screset,}%
        \ifin@\else
          \global\expandafter\let\csname\bbl@GL\endcsname\@undefined
          \xdef\bbl@screset{\bbl@screset,\bbl@GL}%
        \fi
      \fi
    \fi}}
\AtEndOfPackage{%
  \def\bbl@forlang#1#2{\bbl@for#1\bbl@L{\@ifundefined{date#1}{}{#2}}}%
  \let\bbl@scswitch\relax}
\@onlypreamble\EndBabelCommands
\def\EndBabelCommands{%
  \bbl@usehooks{stopcommands}{}%
  \endgroup
  \endgroup
  \bbl@scafter}
%    \end{macrocode}
%    
%    Now we define commands to be used inside |\StartBabelCommands|.
%   
%    \paragraph{Strings} The following macro is the actual definition
%    of |\SetString| when it is ``active''
%
%    First save the ``switcher''. Create it if undefined. Strings are
%    defined only if undefined (ie, like |\providescommmand|). With
%    the event |stringprocess| you can preprocess the string by
%    manipulating the value of |\BabelString|. If there are several
%    hooks assigned to this event, preprocessing is done in the same
%    order as defined.  Finally, the string is set.
% \changes{babel~3.9g}{2013/07/29}{Added \cs{bbl@forlang} to ignore in
%   the preamble unknown languages, as described in the doc.}
% 
%    \begin{macrocode}
\def\bbl@setstring#1#2{%
  \bbl@forlang\bbl@tempa{%
    \edef\bbl@LC{\bbl@tempa\expandafter\@gobble\string#1}%
    \@ifundefined{\bbl@LC}% eg, \germanchaptername
      {\global\expandafter
       \bbl@add\csname\bbl@G\bbl@tempa\expandafter\endcsname\expandafter
         {\expandafter\bbl@scset\expandafter#1\csname\bbl@LC\endcsname}}%
      {}%
    \def\BabelString{#2}%
    \bbl@usehooks{stringprocess}{}%
    \expandafter\bbl@stringdef
      \csname\bbl@LC\expandafter\endcsname\expandafter{\BabelString}}}
%    \end{macrocode}
%
%     Now, some addtional stuff to be used when encoded strings are
%     used. Captions then include |\bbl@encoded| for string to be
%     expanded in case transformations. It is |\relax| by default, but
%     in |\MakeUppercase| and |\MakeLowercase| its value is a modified
%     expandable |\@changed@cmd|.
% 
% \changes{babel~3.9i}{2014/03/13}{Added code to expand captions in
%     case transformations.}
%
%    \begin{macrocode}
\ifx\bbl@opt@strings\relax
  \def\bbl@scset#1#2{\def#1{\bbl@encoded#2}}
  \bbl@patchuclc
  \let\bbl@encoded\relax    
  \def\bbl@encoded@uclc#1{%
    \@inmathwarn#1%
    \expandafter\ifx\csname\cf@encoding\string#1\endcsname\relax
      \expandafter\ifx\csname ?\string#1\endcsname\relax
        \TextSymbolUnavailable#1%
      \else
        \csname ?\string#1\endcsname
      \fi
    \else
      \csname\cf@encoding\string#1\endcsname
    \fi}
\else
  \def\bbl@scset#1#2{\def#1{#2}}
\fi
%    \end{macrocode}
%
%    Define |\SetStringLoop|, which is actually set inside
%    |\StartBabelCommands|. The current definition is
%    somewhat complicated because we need a count, but |\count@| is
%    not under our control (remember |\SetString| may call hooks).
%
% \changes{babel~3.9h}{2013/10/16}{Tidied up and bug fixed - first
%    element expanded prematurely.}
% 
%    \begin{macrocode}
%<<*Macros local to BabelCommands>>
\def\SetStringLoop##1##2{%
    \def\bbl@templ####1{\expandafter\noexpand\csname##1\endcsname}%
    \count@\z@
    \bbl@loop\bbl@tempa{##2}{%
      \advance\count@\@ne
      \toks@\expandafter{\bbl@tempa}%
      \edef\bbl@tempb{%
        \bbl@templ{\romannumeral\count@}{\the\toks@}%
        \count@=\the\count@\relax}%
      \expandafter\SetString\bbl@tempb}}%
%<</Macros local to BabelCommands>>
%    \end{macrocode}
%
%    \paragraph{Delaying code} Now the definition of
%    |\AfterBabelCommands| when it is activated.
%
%    \begin{macrocode}
\def\bbl@aftercmds#1{%
  \toks@\expandafter{\bbl@scafter#1}%
  \xdef\bbl@scafter{\the\toks@}}
%    \end{macrocode}
%
% \paragraph{Case mapping}
%
% The command |\SetCase| provides a way to change the behaviour of
% |\MakeUppercase| and |\MakeLowercase|. |\bbl@tempa| is set by the
% patched |\@uclclist| to the parsing command.
%
% \changes{babel~3.9h}{2013/11/08}{Use \cs{bbl@encstrings} - they
% should be defined always, even if no `strings'}
%    \begin{macrocode}
%<<*Macros local to BabelCommands>>
  \newcommand\SetCase[3][]{%
    \bbl@patchuclc
    \bbl@forlang\bbl@tempa{%
      \expandafter\bbl@encstring
        \csname\bbl@tempa @bbl@uclc\endcsname{\bbl@tempa##1}%
      \expandafter\bbl@encstring
        \csname\bbl@tempa @bbl@uc\endcsname{##2}% 
      \expandafter\bbl@encstring
        \csname\bbl@tempa @bbl@lc\endcsname{##3}}}%
%<</Macros local to BabelCommands>>
%    \end{macrocode}
%
% Macros to deal with case mapping for hyphenation. To decide if the
% document is monolingual or multilingual, we make a rough guess --
% just see if there is a comma in the languages list, built in the
% first pass of the package options. 
%
%    \begin{macrocode}
%<<*Macros local to BabelCommands>>
  \newcommand\SetHyphenMap[1]{%
    \bbl@forlang\bbl@tempa{%
      \expandafter\bbl@stringdef
        \csname\bbl@tempa @bbl@hyphenmap\endcsname{##1}}}
%<</Macros local to BabelCommands>>
%    \end{macrocode}
%
%   There are 3 helper macros which do most of the work for you.
%
%   \begin{macrocode}
\newcommand\BabelLower[2]{% one to one.
  \ifnum\lccode#1=#2\else
    \babel@savevariable{\lccode#1}%
    \lccode#1=#2\relax
  \fi}
\newcommand\BabelLowerMM[4]{% many-to-many
  \@tempcnta=#1\relax
  \@tempcntb=#4\relax
  \def\bbl@tempa{%
    \ifnum\@tempcnta>#2\else
      \@expandtwoargs\BabelLower{\the\@tempcnta}{\the\@tempcntb}%
      \advance\@tempcnta#3\relax
      \advance\@tempcntb#3\relax
      \expandafter\bbl@tempa
    \fi}%
  \bbl@tempa}
\newcommand\BabelLowerMO[4]{% many-to-one
  \@tempcnta=#1\relax
  \def\bbl@tempa{%
    \ifnum\@tempcnta>#2\else
      \@expandtwoargs\BabelLower{\the\@tempcnta}{#4}%
      \advance\@tempcnta#3
      \expandafter\bbl@tempa
    \fi}%
  \bbl@tempa}
%    \end{macrocode}
%
%    The following package options control the behaviour of
%    hyphenation mapping.
%
%    \begin{macrocode}
%<<*More package options>>    
\DeclareOption{hyphenmap=off}{\chardef\bbl@hymapopt\z@}
\DeclareOption{hyphenmap=first}{\chardef\bbl@hymapopt\@ne}
\DeclareOption{hyphenmap=select}{\chardef\bbl@hymapopt\tw@}      
\DeclareOption{hyphenmap=other}{\chardef\bbl@hymapopt\thr@@}
\DeclareOption{hyphenmap=other*}{\chardef\bbl@hymapopt4\relax}
%<</More package options>>    
%    \end{macrocode}
%
%    Initial setup to provide a default behaviour if |hypenmap|
%    is not set.
%
%    \begin{macrocode}
\AtEndOfPackage{%
  \ifx\bbl@hymapopt\@undefined
    \@expandtwoargs\in@{,}{\bbl@language@opts}%
    \chardef\bbl@hymapopt\ifin@4\else\@ne\fi
  \fi}
%    \end{macrocode}
%
% \subsection{Macros common to a number of languages}
%
%  \begin{macro}{\set@low@box}
% \changes{babel~3.2b}{1992/02/16}{Moved macro from language
%    definition files}
%    The following macro is used to lower quotes to the same level as
%    the comma.  It prepares its argument in box register~0.
%    \begin{macrocode}
\def\set@low@box#1{\setbox\tw@\hbox{,}\setbox\z@\hbox{#1}%
    \dimen\z@\ht\z@ \advance\dimen\z@ -\ht\tw@%
    \setbox\z@\hbox{\lower\dimen\z@ \box\z@}\ht\z@\ht\tw@ \dp\z@\dp\tw@}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\save@sf@q}
% \changes{babel~3.2b}{1992/02/16}{Moved macro from language
%    definition files}
%    The macro |\save@sf@q| is used to save and reset the current
%    space factor.
% \changes{babel~3.7f}{2000/09/19}{PR3119, don't start a paragraph in
%    a local group}
%    \begin{macrocode}
\def\save@sf@q#1{\leavevmode
  \begingroup 
    \edef\@SF{\spacefactor\the\spacefactor}#1\@SF
  \endgroup}
%    \end{macrocode}
%  \end{macro}
%
% \changes{babel~3.5c}{1995/06/14}{Repaired a typo (itlaic, PR1652)}
%
%  \subsection{Making glyphs available}
%
%    This section makes a number of glyphs available that either do not
%    exist in the \texttt{OT1} encoding and have to be `faked', or
%    that are not accessible through \file{T1enc.def}.
%
%  \subsubsection{Quotation marks}
%
%  \begin{macro}{\quotedblbase}
%    In the \texttt{T1} encoding the opening double quote at the
%    baseline is available as a separate character, accessible via
%    |\quotedblbase|. In the \texttt{OT1} encoding it is not
%    available, therefore we make it available by lowering the normal
%    open quote character to the baseline.
%    \begin{macrocode}
\ProvideTextCommand{\quotedblbase}{OT1}{%
  \save@sf@q{\set@low@box{\textquotedblright\/}%
    \box\z@\kern-.04em\bbl@allowhyphens}}
%    \end{macrocode}
%    Make sure that when an encoding other than \texttt{OT1} or
%    \texttt{T1} is used this glyph can still be typeset.
%    \begin{macrocode}
\ProvideTextCommandDefault{\quotedblbase}{%
  \UseTextSymbol{OT1}{\quotedblbase}}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\quotesinglbase}
%    We also need the single quote character at the baseline.
%    \begin{macrocode}
\ProvideTextCommand{\quotesinglbase}{OT1}{%
  \save@sf@q{\set@low@box{\textquoteright\/}%
    \box\z@\kern-.04em\bbl@allowhyphens}}
%    \end{macrocode}
%    Make sure that when an encoding other than \texttt{OT1} or
%    \texttt{T1} is used this glyph can still be typeset.
%    \begin{macrocode}
\ProvideTextCommandDefault{\quotesinglbase}{%
  \UseTextSymbol{OT1}{\quotesinglbase}}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\guillemotleft}
%  \begin{macro}{\guillemotright}
%    The guillemet characters are not available in \texttt{OT1}
%    encoding. They are faked.
%    \begin{macrocode}
\ProvideTextCommand{\guillemotleft}{OT1}{%
  \ifmmode
    \ll
  \else
    \save@sf@q{\nobreak
      \raise.2ex\hbox{$\scriptscriptstyle\ll$}\bbl@allowhyphens}%
  \fi}
\ProvideTextCommand{\guillemotright}{OT1}{%
  \ifmmode
    \gg
  \else
    \save@sf@q{\nobreak
      \raise.2ex\hbox{$\scriptscriptstyle\gg$}\bbl@allowhyphens}%
  \fi}
%    \end{macrocode}
%    Make sure that when an encoding other than \texttt{OT1} or
%    \texttt{T1} is used these glyphs can still be typeset.
%    \begin{macrocode}
\ProvideTextCommandDefault{\guillemotleft}{%
  \UseTextSymbol{OT1}{\guillemotleft}}
\ProvideTextCommandDefault{\guillemotright}{%
  \UseTextSymbol{OT1}{\guillemotright}}
%    \end{macrocode}
%  \end{macro}
%  \end{macro}
%
%  \begin{macro}{\guilsinglleft}
%  \begin{macro}{\guilsinglright}
%    The single guillemets are not available in \texttt{OT1}
%    encoding. They are faked.
%    \begin{macrocode}
\ProvideTextCommand{\guilsinglleft}{OT1}{%
  \ifmmode
    <%
  \else
    \save@sf@q{\nobreak
      \raise.2ex\hbox{$\scriptscriptstyle<$}\bbl@allowhyphens}%
  \fi}
\ProvideTextCommand{\guilsinglright}{OT1}{%
  \ifmmode
    >%
  \else
    \save@sf@q{\nobreak
      \raise.2ex\hbox{$\scriptscriptstyle>$}\bbl@allowhyphens}%
  \fi}
%    \end{macrocode}
%    Make sure that when an encoding other than \texttt{OT1} or
%    \texttt{T1} is used these glyphs can still be typeset.
%    \begin{macrocode}
\ProvideTextCommandDefault{\guilsinglleft}{%
  \UseTextSymbol{OT1}{\guilsinglleft}}
\ProvideTextCommandDefault{\guilsinglright}{%
  \UseTextSymbol{OT1}{\guilsinglright}}
%    \end{macrocode}
%  \end{macro}
%  \end{macro}
%
%
%  \subsubsection{Letters}
%
%  \begin{macro}{\ij}
%  \begin{macro}{\IJ}
%    The dutch language uses the letter `ij'. It is available in
%    \texttt{T1} encoded fonts, but not in the \texttt{OT1} encoded
%    fonts. Therefore we fake it for the \texttt{OT1} encoding.
% \changes{dutch-3.7a}{1995/02/04}{Changed the kerning in the faked ij
%    to match the dc-version of it}
% \changes{babel~3.9a}{2012/07/28}{Removed the first \cs{allowhyphens}.
%    Moved the second one just after the kern.}
%    \begin{macrocode}
\DeclareTextCommand{\ij}{OT1}{%
  i\kern-0.02em\bbl@allowhyphens j}
\DeclareTextCommand{\IJ}{OT1}{%
  I\kern-0.02em\bbl@allowhyphens J}
\DeclareTextCommand{\ij}{T1}{\char188}
\DeclareTextCommand{\IJ}{T1}{\char156}
%    \end{macrocode}
%    Make sure that when an encoding other than \texttt{OT1} or
%    \texttt{T1} is used these glyphs can still be typeset.
%    \begin{macrocode}
\ProvideTextCommandDefault{\ij}{%
  \UseTextSymbol{OT1}{\ij}}
\ProvideTextCommandDefault{\IJ}{%
  \UseTextSymbol{OT1}{\IJ}}
%    \end{macrocode}
%  \end{macro}
%  \end{macro}
%
%  \begin{macro}{\dj}
%  \begin{macro}{\DJ}
%    The croatian language needs the letters |\dj| and |\DJ|; they are
%    available in the \texttt{T1} encoding, but not in the
%    \texttt{OT1} encoding by default.
%
%    Some code to construct these glyphs for the \texttt{OT1} encoding
%    was made available to me by Stipcevic Mario,
%    (\texttt{stipcevic@olimp.irb.hr}).
% \changes{babel~3.5f}{1996/03/28}{New definition of \cs{dj}, see PR
%    2058}
%    \begin{macrocode}
\def\crrtic@{\hrule height0.1ex width0.3em}
\def\crttic@{\hrule height0.1ex width0.33em}
\def\ddj@{%
  \setbox0\hbox{d}\dimen@=\ht0
  \advance\dimen@1ex
  \dimen@.45\dimen@
  \dimen@ii\expandafter\rem@pt\the\fontdimen\@ne\font\dimen@
  \advance\dimen@ii.5ex
  \leavevmode\rlap{\raise\dimen@\hbox{\kern\dimen@ii\vbox{\crrtic@}}}}
\def\DDJ@{%
  \setbox0\hbox{D}\dimen@=.55\ht0
  \dimen@ii\expandafter\rem@pt\the\fontdimen\@ne\font\dimen@
  \advance\dimen@ii.15ex %            correction for the dash position
  \advance\dimen@ii-.15\fontdimen7\font %     correction for cmtt font
  \dimen\thr@@\expandafter\rem@pt\the\fontdimen7\font\dimen@
  \leavevmode\rlap{\raise\dimen@\hbox{\kern\dimen@ii\vbox{\crttic@}}}}
%
\DeclareTextCommand{\dj}{OT1}{\ddj@ d}
\DeclareTextCommand{\DJ}{OT1}{\DDJ@ D}
%    \end{macrocode}
%    Make sure that when an encoding other than \texttt{OT1} or
%    \texttt{T1} is used these glyphs can still be typeset.
%    \begin{macrocode}
\ProvideTextCommandDefault{\dj}{%
  \UseTextSymbol{OT1}{\dj}}
\ProvideTextCommandDefault{\DJ}{%
  \UseTextSymbol{OT1}{\DJ}}
%    \end{macrocode}
%  \end{macro}
%  \end{macro}
%
%  \begin{macro}{\SS}
%    For the \texttt{T1} encoding |\SS| is defined and selects a
%    specific glyph from the font, but for other encodings it is not
%    available. Therefore we make it available here.
%    \begin{macrocode}
\DeclareTextCommand{\SS}{OT1}{SS}
\ProvideTextCommandDefault{\SS}{\UseTextSymbol{OT1}{\SS}}
%    \end{macrocode}
%  \end{macro}
%
% \subsubsection{Shorthands for quotation marks}
%
%    Shorthands are provided for a number of different quotation
%    marks, which make them usable both outside and inside mathmode.
%
%  \begin{macro}{\glq}
%  \begin{macro}{\grq}
% \changes{babel~3.7a}{1997/04/25}{Make the definition of \cs{grq}
%    dependent on the font encoding}
% \changes{babel~3.8b}{2004/05/02}{Made \cs{glq} fontencoding
%    dependent as well} 
%    The `german' single quotes.
%    \begin{macrocode}
\ProvideTextCommand{\glq}{OT1}{%
  \textormath{\quotesinglbase}{\mbox{\quotesinglbase}}}
\ProvideTextCommand{\glq}{T1}{%
  \textormath{\quotesinglbase}{\mbox{\quotesinglbase}}}
\ProvideTextCommandDefault{\glq}{\UseTextSymbol{OT1}\glq}
%    \end{macrocode}
%    The definition of |\grq| depends on the fontencoding. With
%    \texttt{T1} encoding no extra kerning is needed.
%    \begin{macrocode}
\ProvideTextCommand{\grq}{T1}{%
  \textormath{\textquoteleft}{\mbox{\textquoteleft}}}
\ProvideTextCommand{\grq}{OT1}{%
  \save@sf@q{\kern-.0125em%
  \textormath{\textquoteleft}{\mbox{\textquoteleft}}%
  \kern.07em\relax}}
\ProvideTextCommandDefault{\grq}{\UseTextSymbol{OT1}\grq}
%    \end{macrocode}
%  \end{macro}
%  \end{macro}
%
%  \begin{macro}{\glqq}
%  \begin{macro}{\grqq}
% \changes{babel~3.7a}{1997/04/25}{Make the definition of \cs{grqq}
%    dependent on the font encoding}
% \changes{babel~3.8b}{2004/05/02}{Made \cs{grqq} fontencoding
%    dependent as well} 
%    The `german' double quotes.
%    \begin{macrocode}
\ProvideTextCommand{\glqq}{OT1}{%
  \textormath{\quotedblbase}{\mbox{\quotedblbase}}}
\ProvideTextCommand{\glqq}{T1}{%
  \textormath{\quotedblbase}{\mbox{\quotedblbase}}}
\ProvideTextCommandDefault{\glqq}{\UseTextSymbol{OT1}\glqq}
%    \end{macrocode}
%    The definition of |\grqq| depends on the % fontencoding. With
%    \texttt{T1} encoding no extra kerning is needed.
%    \begin{macrocode}
\ProvideTextCommand{\grqq}{T1}{%
  \textormath{\textquotedblleft}{\mbox{\textquotedblleft}}}
\ProvideTextCommand{\grqq}{OT1}{%
  \save@sf@q{\kern-.07em%
  \textormath{\textquotedblleft}{\mbox{\textquotedblleft}}%
  \kern.07em\relax}}
\ProvideTextCommandDefault{\grqq}{\UseTextSymbol{OT1}\grqq}
%    \end{macrocode}
%  \end{macro}
%  \end{macro}
%
%  \begin{macro}{\flq}
%  \begin{macro}{\frq}
% \changes{babel~3.5f}{1995/08/07}{corrected spelling of
%    \cs{quilsingl...}}
% \changes{babel~3.5f}{1995/09/05}{now use \cs{textormath} in these
%    definitions}
% \changes{babel~3.8b}{2004/05/02}{Made \cs{flq} and \cs{frq}
%    fontencoding dependent} 
%    The `french' single guillemets.
%    \begin{macrocode}
\ProvideTextCommand{\flq}{OT1}{%
  \textormath{\guilsinglleft}{\mbox{\guilsinglleft}}}
\ProvideTextCommand{\flq}{T1}{%
  \textormath{\guilsinglleft}{\mbox{\guilsinglleft}}}
\ProvideTextCommandDefault{\flq}{\UseTextSymbol{OT1}\flq}
%    \end{macrocode}
%    
%    \begin{macrocode}
\ProvideTextCommand{\frq}{OT1}{%
  \textormath{\guilsinglright}{\mbox{\guilsinglright}}}
\ProvideTextCommand{\frq}{T1}{%
  \textormath{\guilsinglright}{\mbox{\guilsinglright}}}
\ProvideTextCommandDefault{\frq}{\UseTextSymbol{OT1}\frq}
%    \end{macrocode}
%  \end{macro}
%  \end{macro}
%
%  \begin{macro}{\flqq}
%  \begin{macro}{\frqq}
% \changes{babel~3.5f}{1995/08/07}{corrected spelling of
%    \cs{quillemot...}}
% \changes{babel~3.5f}{1995/09/05}{now use \cs{textormath} in these
%    definitions}
% \changes{babel~3.8b}{2004/05/02}{Made \cs{flqq} and \cs{frqq}
%    fontencoding dependent} 
%    The `french' double guillemets.
%    \begin{macrocode}
\ProvideTextCommand{\flqq}{OT1}{%
  \textormath{\guillemotleft}{\mbox{\guillemotleft}}}
\ProvideTextCommand{\flqq}{T1}{%
  \textormath{\guillemotleft}{\mbox{\guillemotleft}}}
\ProvideTextCommandDefault{\flqq}{\UseTextSymbol{OT1}\flqq}
%    \end{macrocode}
%    
%    \begin{macrocode}
\ProvideTextCommand{\frqq}{OT1}{%
  \textormath{\guillemotright}{\mbox{\guillemotright}}}
\ProvideTextCommand{\frqq}{T1}{%
  \textormath{\guillemotright}{\mbox{\guillemotright}}}
\ProvideTextCommandDefault{\frqq}{\UseTextSymbol{OT1}\frqq}
%    \end{macrocode}
%  \end{macro}
%  \end{macro}
%
%  \subsubsection{Umlauts and tremas}
%
%    The command |\"| needs to have a different effect for different
%    languages. For German for instance, the `umlaut' should be
%    positioned lower than the default position for placing it over
%    the letters a, o, u, A, O and U. When placed over an e, i, E or I
%    it can retain its normal position. For Dutch the same glyph is
%    always placed in the lower position.
%
%  \begin{macro}{\umlauthigh}
% \changes{v3.8a}{2004/02/19}{Use \cs{leavevmode}\cs{bgroup} to
%    prevent problems when this command occurs in vertical mode.}
%  \begin{macro}{\umlautlow}
%    To be able to provide both positions of |\"| we provide two
%    commands to switch the positioning, the default will be
%    |\umlauthigh| (the normal positioning).
%    \begin{macrocode}
\def\umlauthigh{%
  \def\bbl@umlauta##1{\leavevmode\bgroup%
      \expandafter\accent\csname\f@encoding dqpos\endcsname
      ##1\bbl@allowhyphens\egroup}%
  \let\bbl@umlaute\bbl@umlauta}
\def\umlautlow{%
  \def\bbl@umlauta{\protect\lower@umlaut}}
\def\umlautelow{%
  \def\bbl@umlaute{\protect\lower@umlaut}}
\umlauthigh
%    \end{macrocode}
%  \end{macro}
%  \end{macro}
%
%  \begin{macro}{\lower@umlaut}
%    The command |\lower@umlaut| is used to position the |\"| closer
%    the the letter.
%
%    We want the umlaut character lowered, nearer to the letter. To do
%    this we need an extra \meta{dimen} register.
%    \begin{macrocode}
\expandafter\ifx\csname U@D\endcsname\relax
  \csname newdimen\endcsname\U@D
\fi
%    \end{macrocode}
%    The following code fools \TeX's \texttt{make\_accent} procedure
%    about the current x-height of the font to force another placement
%    of the umlaut character.
%    First we have to save the current x-height of the font, because
%    we'll change this font dimension and this is always done
%    globally.
% \changes{v3.8a}{2004/02/19}{Use \cs{leavevmode}\cs{bgroup} to
%    prevent problems when this command occurs in vertical mode.}
%
%    Then we compute the new x-height in such a way that the umlaut
%    character is lowered to the base character.  The value of
%    \texttt{.45ex} depends on the \MF\ parameters with which the
%    fonts were built.  (Just try out, which value will look best.)
%    If the new x-height is too low, it is not changed.
%    Finally we call the |\accent| primitive, reset the old x-height
%    and insert the base character in the argument.
% \changes{babel~3.5f}{1996/04/02}{Added a \cs{allowhyphens}}
% \changes{babel~3.5f}{1996/06/25}{removed \cs{allowhyphens}}
%    \begin{macrocode}
\def\lower@umlaut#1{%
  \leavevmode\bgroup
    \U@D 1ex%
    {\setbox\z@\hbox{%
      \expandafter\char\csname\f@encoding dqpos\endcsname}%
      \dimen@ -.45ex\advance\dimen@\ht\z@
      \ifdim 1ex<\dimen@ \fontdimen5\font\dimen@ \fi}%
    \expandafter\accent\csname\f@encoding dqpos\endcsname
    \fontdimen5\font\U@D #1%
  \egroup}
%    \end{macrocode}
%  \end{macro}
%
%    For all vowels we declare |\"| to be a composite command which
%    uses |\bbl@umlauta| or |\bbl@umlaute| to position the umlaut
%    character. We need to be sure that these definitions override the
%    ones that are provided when the package \pkg{fontenc} with
%    option \Lopt{OT1} is used. Therefore these declarations are
%    postponed until the beginning of the document. Note these
%    definitions only apply to some languages, but 
%    babel sets them for \textit{all} languages -- you may want to
%    redefine |\bbl@umlauta| and/or |\bbl@umlaute| for a language
%    in the corresponding |ldf| (using the babel switching mechanism,
%    of course).
%    \begin{macrocode}
\AtBeginDocument{%
  \DeclareTextCompositeCommand{\"}{OT1}{a}{\bbl@umlauta{a}}%
  \DeclareTextCompositeCommand{\"}{OT1}{e}{\bbl@umlaute{e}}%
  \DeclareTextCompositeCommand{\"}{OT1}{i}{\bbl@umlaute{\i}}%
  \DeclareTextCompositeCommand{\"}{OT1}{\i}{\bbl@umlaute{\i}}%
  \DeclareTextCompositeCommand{\"}{OT1}{o}{\bbl@umlauta{o}}%
  \DeclareTextCompositeCommand{\"}{OT1}{u}{\bbl@umlauta{u}}%
  \DeclareTextCompositeCommand{\"}{OT1}{A}{\bbl@umlauta{A}}%
  \DeclareTextCompositeCommand{\"}{OT1}{E}{\bbl@umlaute{E}}%
  \DeclareTextCompositeCommand{\"}{OT1}{I}{\bbl@umlaute{I}}%
  \DeclareTextCompositeCommand{\"}{OT1}{O}{\bbl@umlauta{O}}%
  \DeclareTextCompositeCommand{\"}{OT1}{U}{\bbl@umlauta{U}}%
}
%    \end{macrocode}
%
%    Finally, the default is to use English as the main language.
% \changes{babel~3.6c}{1997/01/05}{When \file{hyphen.cfg} is not
%    loaded in the format \cs{l@english} might not be defined; assume
%    english is language 0}
% \changes{babel~3.9a}{2012-05-17}{Languages are best assigned with
%    \cs{chardef}, not \cs{let}}
%    \begin{macrocode}
\ifx\l@english\@undefined
  \chardef\l@english\z@
\fi
\main@language{english}
%    \end{macrocode}
%
%    Now we load definition files for engines.
%
%    \begin{macrocode}
\ifcase\bbl@engine\or
  \input luababel.def
\or
  \input xebabel.def
\fi
%    \end{macrocode}
%
% \section{The kernel of Babel (only \LaTeX)}
%
% \subsection{The redefinition of the style commands}
%
%    The rest of the code in this file can only be processed by
%    \LaTeX, so we check the current format. If it is plain \TeX,
%    processing should stop here. But, because of the need to limit
%    the scope of the definition of |\format|, a macro that is used
%    locally in the following |\if|~statement, this comparison is done
%    inside a group. To prevent \TeX\ from complaining about an
%    unclosed group, the processing of the command |\endinput| is
%    deferred until after the group is closed. This is accomplished by
%    the command |\aftergroup|.
%    \begin{macrocode}
{\def\format{lplain}
\ifx\fmtname\format
\else
  \def\format{LaTeX2e}
  \ifx\fmtname\format
  \else
    \aftergroup\endinput
  \fi
\fi}
%    \end{macrocode}
%
% \subsection{Cross referencing macros}
%
%    The \LaTeX\ book states:
%  \begin{quote}
%    The \emph{key} argument is any sequence of letters, digits, and
%    punctuation symbols; upper- and lowercase letters are regarded as
%    different.
%  \end{quote}
%    When the above quote should still be true when a document is
%    typeset in a language that has active characters, special care
%    has to be taken of the category codes of these characters when
%    they appear in an argument of the cross referencing macros.
%
%    When a cross referencing command processes its argument, all
%    tokens in this argument should be character tokens with category
%    `letter' or `other'.
%
%    The only way to accomplish this in most cases is to use the trick
%    described in the \TeX book~\cite{DEK} (Appendix~D, page~382).
%    The primitive |\meaning| applied to a token expands to the
%    current meaning of this token.  For example, `|\meaning\A|' with
%    |\A| defined as `|\def\A#1{\B}|' expands to the characters
%    `|macro:#1->\B|' with all category codes set to `other' or
%    `space'.
%  \begin{macro}{\newlabel}
% \changes{babel~3.5f}{1995/11/15}{Now use \cs{bbl@redefine}}
%    The macro |\label| writes a line with a |\newlabel| command
%    into the |.aux| file to define labels.
%    \begin{macrocode}
%\bbl@redefine\newlabel#1#2{%
%  \@safe@activestrue\org@newlabel{#1}{#2}\@safe@activesfalse}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\@newl@bel}
% \changes{babel~3.6i}{1997/03/01}{Now redefine \cs{@newl@bel} instead
%    of \cs{@lbibitem} and \cs{newlabel}}
%    We need to change the definition of the \LaTeX-internal macro
%    |\@newl@bel|. This is needed because we need to make sure that
%    shorthand characters expand to their non-active version.
%
%    The following package options control which macros are to be
%    redefined.
%    \begin{macrocode}
%<<*More package options>>
\DeclareOption{safe=none}{\let\bbl@opt@safe\@empty}
\DeclareOption{safe=bib}{\def\bbl@opt@safe{B}}
\DeclareOption{safe=ref}{\def\bbl@opt@safe{R}}
%<</More package options>>
%    \end{macrocode}
%
%    First we open a new group to keep the changed setting of
%    |\protect| local and then we set the |@safe@actives| switch to
%    true to make sure that any shorthand that appears in any of the
%    arguments immediately expands to its non-active self.
% \changes{babel~3.7a}{1997/12/19}{Call \cs{@safe@activestrue}
%    directly}
%    \begin{macrocode}
\ifx\bbl@opt@safe\@empty\else
  \def\@newl@bel#1#2#3{%
   {\@safe@activestrue
    \@ifundefined{#1@#2}%
       \relax
       {\gdef\@multiplelabels{%
          \@latex@warning@no@line{There were multiply-defined labels}}%
        \@latex@warning@no@line{Label `#2' multiply defined}}%
    \global\@namedef{#1@#2}{#3}}}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\@testdef}
%    An internal \LaTeX\ macro used to test if the labels that have
%    been written on the |.aux| file have changed.  It is called by
%    the |\enddocument| macro. This macro needs to be completely
%    rewritten, using |\meaning|. The reason for this is that in some
%    cases the expansion of |\#1@#2| contains the same characters as
%    the |#3|; but the character codes differ. Therefore \LaTeX\ keeps
%    reporting that the labels may have changed.
% \changes{babel~3.4g}{1994/08/30}{Moved the \cs{def} inside the
%    macrocode environment}
% \changes{babel~3.5f}{1995/11/15}{Now use \cs{bbl@redefine}}
% \changes{babel~3.5f}{1996/01/09}{Complete rewrite of this macro as
%    the same character ended up with different category codes in the
%    labels that are being compared. Now use \cs{meaning}}
% \changes{babel~3.5f}{1996/01/16}{Use \cs{strip@prefix} only on
%    \cs{bbl@tempa} when it is not \cs{relax}}
% \changes{babel~3.6i}{1997/02/28}{Make sure that shorthands don't get
%    expanded at the wrong moment.}
% \changes{babel~3.6i}{1997/03/01}{\cs{@safe@activesfalse} is now
%    part of the label definition}
% \changes{babel~3.7a}{1998/03/13}{Removed \cs{@safe@activesfalse}
%    from the label definition}
%    \begin{macrocode}
  \CheckCommand*\@testdef[3]{%
    \def\reserved@a{#3}%
    \expandafter\ifx\csname#1@#2\endcsname\reserved@a
    \else
      \@tempswatrue
    \fi}
%    \end{macrocode}
%    Now that we made sure that |\@testdef| still has the same
%    definition we can rewrite it. First we make the shorthands
%    `safe'.
%    \begin{macrocode}
  \def\@testdef#1#2#3{%
    \@safe@activestrue
%    \end{macrocode}
%    Then we use |\bbl@tempa| as an `alias' for the macro that
%    contains the label which is being checked.
%    \begin{macrocode}
    \expandafter\let\expandafter\bbl@tempa\csname #1@#2\endcsname
%    \end{macrocode}
%    Then we define |\bbl@tempb| just as |\@newl@bel| does it.
%    \begin{macrocode}
    \def\bbl@tempb{#3}%
    \@safe@activesfalse
%    \end{macrocode}
%    When the label is defined we replace the definition of
%    |\bbl@tempa| by its meaning.
%    \begin{macrocode}
    \ifx\bbl@tempa\relax
    \else
      \edef\bbl@tempa{\expandafter\strip@prefix\meaning\bbl@tempa}%
    \fi
%    \end{macrocode}
%    We do the same for |\bbl@tempb|.
%    \begin{macrocode}
    \edef\bbl@tempb{\expandafter\strip@prefix\meaning\bbl@tempb}%
%    \end{macrocode}
%    If the label didn't change, |\bbl@tempa| and |\bbl@tempb| should
%    be identical macros.
%    \begin{macrocode}
    \ifx\bbl@tempa\bbl@tempb
    \else
      \@tempswatrue
    \fi}
\fi
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\ref}
%  \begin{macro}{\pageref}
%    The same holds for the macro |\ref| that references a label
%    and |\pageref| to reference a page. So we redefine |\ref| and
%    |\pageref|. While we change these macros, we make them robust as
%    well (if they weren't already) to prevent problems if they should
%    become expanded at the wrong moment.
% \changes{babel~3.5b}{1995/03/07}{Made \cs{ref} and \cs{pageref}
%    robust (PR1353)}
% \changes{babel~3.5d}{1995/07/04}{use a different control sequence
%    while making \cs{ref} and \cs{pageref} robust}
% \changes{babel~3.5f}{1995/11/06}{redefine \cs*{ref } if it exists
%    instead of \cs{ref}}
% \changes{babel~3.5f}{1995/11/15}{Now use \cs{bbl@redefinerobust}}
% \changes{babel~3.5f}{1996/01/19}{redefine \cs{\@setref} instead of
%    \cs{ref} and \cs{pageref} in \LaTeXe.}
% \changes{babel~3.5f}{1996/01/21}{Reverse the previous change as it
%    inhibits the use of active characters in labels}
%    \begin{macrocode}
\@expandtwoargs\in@{R}\bbl@opt@safe
\ifin@
  \bbl@redefinerobust\ref#1{%
    \@safe@activestrue\org@ref{#1}\@safe@activesfalse}
  \bbl@redefinerobust\pageref#1{%
    \@safe@activestrue\org@pageref{#1}\@safe@activesfalse}
\else
  \let\org@ref\ref
  \let\org@pageref\pageref
\fi
%    \end{macrocode}
%  \end{macro}
%  \end{macro}
%
%  \begin{macro}{\@citex}
% \changes{babel~3.5f}{1995/11/15}{Now use \cs{bbl@redefine}}
%    The macro used to cite from a bibliography, |\cite|, uses an
%    internal macro, |\@citex|.
%    It is this internal macro that picks up the argument(s),
%    so we redefine this internal macro and leave |\cite| alone. The
%    first argument is used for typesetting, so the shorthands need
%    only be deactivated in the second argument.
% \changes{babel~3.7g}{2000/10/01}{The shorthands need to be
%    deactivated for the second argument of \cs{@citex} only.}
%    \begin{macrocode}
\@expandtwoargs\in@{B}\bbl@opt@safe
\ifin@
  \bbl@redefine\@citex[#1]#2{%
    \@safe@activestrue\edef\@tempa{#2}\@safe@activesfalse
    \org@@citex[#1]{\@tempa}}
%    \end{macrocode}
%    Unfortunately, the packages \pkg{natbib} and \pkg{cite} need a
%    different definition of |\@citex|...
%    To begin with, \pkg{natbib} has a definition for |\@citex| with
%    \emph{three} arguments... We only know that a package is loaded
%    when |\begin{document}| is executed, so we need to postpone the
%    different redefinition.
%    \begin{macrocode}
  \AtBeginDocument{%
    \@ifpackageloaded{natbib}{%
%    \end{macrocode}
%    Notice that we use |\def| here instead of |\bbl@redefine| because
%    |\org@@citex| is already defined and we don't want to overwrite
%    that definition (it would result in parameter stack overflow
%    because of a circular definition).
%
%   (Recent versions of natbib change dynamically |\@citex|, so PR4087
%     doesn't seem fixable in a simple way. Just load natbib before.)
%    \begin{macrocode}
    \def\@citex[#1][#2]#3{%
      \@safe@activestrue\edef\@tempa{#3}\@safe@activesfalse
      \org@@citex[#1][#2]{\@tempa}}%
    }{}}
%    \end{macrocode}
%    The package \pkg{cite} has a definition of |\@citex| where the
%    shorthands need to be turned off in both arguments.
%    \begin{macrocode}
  \AtBeginDocument{%
    \@ifpackageloaded{cite}{%
      \def\@citex[#1]#2{%
        \@safe@activestrue\org@@citex[#1]{#2}\@safe@activesfalse}%
      }{}}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\nocite}
% \changes{babel~3.5f}{1995/11/15}{Now use \cs{bbl@redefine}}
%    The macro |\nocite| which is used to instruct BiB\TeX\ to
%    extract uncited references from the database.
%    \begin{macrocode}
  \bbl@redefine\nocite#1{%
    \@safe@activestrue\org@nocite{#1}\@safe@activesfalse}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\bibcite}
% \changes{babel~3.5f}{1995/11/15}{Now use \cs{bbl@redefine}}
%    The macro that is used in the |.aux| file to define citation
%    labels. When packages such as \pkg{natbib} or \pkg{cite} are not
%    loaded its second argument is used to typeset the citation
%    label. In that case, this second argument can contain active
%    characters but is used in an environment where
%    |\@safe@activestrue| is in effect. This switch needs to be reset
%    inside the |\hbox| which contains the citation label. In order to
%    determine during \file{.aux} file processing which definition of
%    |\bibcite| is needed we define |\bibcite| in such a way that it
%    redefines itself with the proper definition.
% \changes{babel~3.6s}{1999/04/13}{Need to determine `online' which
%    definition of \cs{bibcite} is needed}
% \changes{babel~3.6v}{1999/04/21}{Also check for \pkg{cite} it can't
%    handle \cs{@safe@activesfalse} in its second argument}
%    \begin{macrocode}
  \bbl@redefine\bibcite{%
%    \end{macrocode}
%    We call |\bbl@cite@choice| to select the proper definition for
%    |\bibcite|. This new definition is then activated.
%    \begin{macrocode}
    \bbl@cite@choice
    \bibcite}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\bbl@bibcite}
% \changes{babel~3.6v}{1999/04/21}{Macro \cs{bbl@bibcite} added}
%    The macro |\bbl@bibcite| holds the definition of |\bibcite|
%    needed when neither \pkg{natbib} nor \pkg{cite} is loaded.
%    \begin{macrocode}
  \def\bbl@bibcite#1#2{%
    \org@bibcite{#1}{\@safe@activesfalse#2}}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\bbl@cite@choice}
% \changes{babel~3.6v}{1999/04/21}{Macro \cs{bbl@cite@choice} added}
%    The macro |\bbl@cite@choice| determines which definition of
%    |\bibcite| is needed.
%    \begin{macrocode}
  \def\bbl@cite@choice{%
%    \end{macrocode}
%    First we give |\bibcite| its default definition.
%    \begin{macrocode}
    \global\let\bibcite\bbl@bibcite
%    \end{macrocode}
%    Then, when \pkg{natbib} is loaded we restore the original
%    definition of |\bibcite|.
%    \begin{macrocode}
    \@ifpackageloaded{natbib}{\global\let\bibcite\org@bibcite}{}%
%    \end{macrocode}
%    For \pkg{cite} we do the same.
%    \begin{macrocode}
    \@ifpackageloaded{cite}{\global\let\bibcite\org@bibcite}{}%
%    \end{macrocode}
%    Make sure this only happens once.
%    \begin{macrocode}
    \global\let\bbl@cite@choice\relax}
%    \end{macrocode}
%
%    When a document is run for the first time, no \file{.aux} file is
%    available, and |\bibcite| will not yet be properly defined. In
%    this case, this has to happen before the document starts.
%    \begin{macrocode}
  \AtBeginDocument{\bbl@cite@choice}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\@bibitem}
% \changes{babel~3.5f}{1995/11/15}{Now use \cs{bbl@redefine}}
%    One of the two internal \LaTeX\ macros called by |\bibitem|
%    that write the citation label on the |.aux| file.
%    \begin{macrocode}
  \bbl@redefine\@bibitem#1{%
    \@safe@activestrue\org@@bibitem{#1}\@safe@activesfalse}
\else
  \let\org@nocite\nocite
  \let\org@@citex\@citex
  \let\org@bibcite\bibcite
  \let\org@@bibitem\@bibitem
\fi
%    \end{macrocode}
%  \end{macro}
%
%  \subsection{Marks}
%
%  \begin{macro}{\markright}
% \changes{babel~3.6i}{1997/03/15}{Added redefinition of \cs{mark...}
%    commands}
%    Because the output routine is asynchronous, we must
%    pass the current language attribute to the head lines, together
%    with the text that is put into them. To achieve this we need to
%    adapt the definition of |\markright| and |\markboth| somewhat.
% \changes{babel~3.7c}{1999/04/08}{Removed the use of \cs{head@lang}
%    (PR 2990)}
% \changes{babel~3.7c}{1999/04/09}{Avoid expanding the arguments by
%    storing them in token registers}
% \changes{babel~3.7m}{2003/11/15}{added \cs{bbl@restore@actives} to
%    the mark}
% \changes{babel~3.8c}{2004/05/26}{No need to add \emph{anything} to
%    an empty mark; prevented this by checking the contents of the
%    argument}
% \changes{babel~3.8f}{2005/05/15}{Make the definition independent of
%    the original definition; expand \cs{languagename} before passing
%    it into the token registers} 
%    \begin{macrocode}
\bbl@redefine\markright#1{%
%    \end{macrocode}
%    First of all we temporarily store the language switching command,
%    using an expanded definition in order to get the current value of
%    |\languagename|. 
%    \begin{macrocode}
  \edef\bbl@tempb{\noexpand\protect
    \noexpand\foreignlanguage{\languagename}}%
%    \end{macrocode}
%    Then, we check whether the argument is empty; if it is, we
%    just make sure the scratch token register is empty.
%    \begin{macrocode}
  \def\bbl@arg{#1}%
  \ifx\bbl@arg\@empty
    \toks@{}%
  \else
%    \end{macrocode}
%    Next, we store the argument to |\markright| in the scratch token
%    register, together with the expansion of |\bbl@tempb| (containing
%    the language switching command) as defined before. This way
%    these commands will not be expanded by using |\edef| later
%    on, and we make sure that the text is typeset using the
%    correct language settings. While doing so, we make sure that
%    active characters that may end up in the mark are not disabled by
%    the output routine kicking in while \cs{@safe@activestrue} is in
%    effect.
%    \begin{macrocode}
    \expandafter\toks@\expandafter{%
             \bbl@tempb{\protect\bbl@restore@actives#1}}%
  \fi
%    \end{macrocode}
%    Then we define a temporary control sequence using |\edef|.
%    \begin{macrocode}
  \edef\bbl@tempa{%
%    \end{macrocode}
%     When |\bbl@tempa| is executed, only |\languagename| will be
%    expanded, because of the way the token register was filled.
%    \begin{macrocode}
    \noexpand\org@markright{\the\toks@}}%
  \bbl@tempa
}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\markboth}
%  \begin{macro}{\@mkboth}
%    The definition of |\markboth| is equivalent to that of
%    |\markright|, except that we need two token registers. The
%    documentclasses \cls{report} and \cls{book} define and set the
%    headings for the page. While doing so they also store a copy of
%    |\markboth| in |\@mkboth|. Therefore we need to check whether
%    |\@mkboth| has already been set. If so we neeed to do that again
%    with the new definition of |\makrboth|.
% \changes{babel~3.7m}{2003/11/15}{added \cs{bbl@restore@actives} to
%    the mark}
% \changes{babel~3.8c}{2004/05/26}{No need to add \emph{anything} to
%    an empty mark, prevented this by checking the contents of the
%    arguments} 
% \changes{babel~3.8f}{2005/05/15}{Make the definition independent of
%    the original definition; expand \cs{languagename} before passing
%    it into the token registers} 
% \changes{babel~3.8j}{2008/03/21}{Added setting of \cs{@mkboth} (PR
%    3826)} 
%    \begin{macrocode}
\ifx\@mkboth\markboth
  \def\bbl@tempc{\let\@mkboth\markboth}
\else
  \def\bbl@tempc{}
\fi
%    \end{macrocode}
%    Now we can start the new definition of |\markboth|
%    \begin{macrocode}
\bbl@redefine\markboth#1#2{%
  \edef\bbl@tempb{\noexpand\protect
    \noexpand\foreignlanguage{\languagename}}%
  \def\bbl@arg{#1}%
  \ifx\bbl@arg\@empty
    \toks@{}%
  \else
   \expandafter\toks@\expandafter{%
             \bbl@tempb{\protect\bbl@restore@actives#1}}%
  \fi
  \def\bbl@arg{#2}%
  \ifx\bbl@arg\@empty
    \toks8{}%
  \else
    \expandafter\toks8\expandafter{%
             \bbl@tempb{\protect\bbl@restore@actives#2}}%
  \fi
  \edef\bbl@tempa{%
    \noexpand\org@markboth{\the\toks@}{\the\toks8}}%
  \bbl@tempa
}
%    \end{macrocode}
%    and copy it to |\@mkboth| if necesary.
%    \begin{macrocode}
\bbl@tempc
%    \end{macrocode}
%  \end{macro}
%  \end{macro}
%
%  \subsection{Preventing clashes with other packages}
%
%  \subsubsection{\pkg{ifthen}}
%
%  \begin{macro}{\ifthenelse}
% \changes{babel~3.5g}{1996/08/11}{Redefinition of \cs{ifthenelse}
%    added to circumvent problems with \cs{pageref} in the argument of
%    \cs{isodd}}
% \changes{babel~3.9a}{2012/09/07}{Redefine only if `ref' is `safe'}%
% \changes{babel~3.9a}{2013/01/03}{Moved to babel.def}
%    Sometimes a document writer wants to create a special effect
%    depending on the page a certain fragment of text appears on. This
%    can be achieved by the following piece of code:
% \begin{verbatim}
%    \ifthenelse{\isodd{\pageref{some:label}}}
%               {code for odd pages}
%               {code for even pages}
%\end{verbatim}
%    In order for this to work the argument of |\isodd| needs to be
%    fully expandable. With the above redefinition of |\pageref| it is
%    not in the case of this example. To overcome that, we add some
%    code to the definition of |\ifthenelse| to make things work.
%
%    The first thing we need to do is check if the package
%    \pkg{ifthen} is loaded. This should be done at |\begin{document}|
%    time.
%    \begin{macrocode}
\@expandtwoargs\in@{R}\bbl@opt@safe
\ifin@
  \AtBeginDocument{%
    \@ifpackageloaded{ifthen}{%
%    \end{macrocode}
%    Then we can redefine |\ifthenelse|:
% \changes{babel~3.6f}{1997/01/14}{\cs{ifthenelse} needs to be long}
% \changes{babel~3.9a}{2012/06/22}{\cs{ref} is also taken into account}
%    \begin{macrocode}
      \bbl@redefine@long\ifthenelse#1#2#3{%
%    \end{macrocode}
%    We want to revert the definition of |\pageref| and |\ref| to
%    their original definition for the duration of |\ifthenelse|,
%    so we first need to store their current meanings.
%    \begin{macrocode}
        \let\bbl@tempa\pageref
        \let\pageref\org@pageref
        \let\bbl@tempb\ref
        \let\ref\org@ref
%    \end{macrocode}
%    Then we can set the |\@safe@actives| switch and call the original
%    |\ifthenelse|. In order to be able to use shorthands in the
%    second and third arguments of |\ifthenelse| the resetting of the
%    switch \emph{and} the definition of |\pageref| happens inside
%    those arguments.  When the package wasn't loaded we do nothing.
% \changes{babel~3.6i}{1997/02/25}{Now reset the @safe@actives switch
%    inside the 2nd and 3rd arguments of \cs{ifthenelse}}
% \changes{babel~3.7f}{2000/06/29}{\cs{pageref} needs to have its
%    babel definition reinstated in the second and third arguments}
%    \begin{macrocode}
        \@safe@activestrue
        \org@ifthenelse{#1}{%
          \let\pageref\bbl@tempa
          \let\ref\bbl@tempb
          \@safe@activesfalse
          #2}{%
          \let\pageref\bbl@tempa
          \let\ref\bbl@tempb
          \@safe@activesfalse
          #3}%
        }%
      }{}%
    }
%    \end{macrocode}
%  \end{macro}
%
%  \subsubsection{\pkg{varioref}}
%
%  \begin{macro}{\@@vpageref}
% \changes{babel~3.6a}{1996/10/29}{Redefinition of \cs{@@vpageref}
%    added to circumvent problems with active \texttt{:} in the
%    argument of \cs{vref} when \pkg{varioref} is used}
%  \begin{macro}{\vrefpagenum}
% \changes{babel~3.7o}{2003/11/18}{Added redefinition of
%    \cs{vrefpagenum} which deals with ranges of pages}
%  \begin{macro}{\Ref}
% \changes{babel~3.8g}{2005/05/21}{We also need to adapt \cs{Ref}
%    which needs to be able to uppercase the first letter of the
%    expansion of \cs{ref}} 
%    When the package varioref is in use we need to modify its
%    internal command |\@@vpageref| in order to prevent problems when
%    an active character ends up in the argument of |\vref|.
%    \begin{macrocode}
  \AtBeginDocument{%
    \@ifpackageloaded{varioref}{%
      \bbl@redefine\@@vpageref#1[#2]#3{%
        \@safe@activestrue
        \org@@@vpageref{#1}[#2]{#3}%
        \@safe@activesfalse}%
%    \end{macrocode}
%    The same needs to happen for |\vrefpagenum|.
%    \begin{macrocode}
      \bbl@redefine\vrefpagenum#1#2{%
        \@safe@activestrue
        \org@vrefpagenum{#1}{#2}%
        \@safe@activesfalse}%
%    \end{macrocode}
%    The package \pkg{varioref} defines |\Ref| to be a robust command
%    wich uppercases the first character of the reference text. In
%    order to be able to do that it needs to access the exandable form
%    of |\ref|. So we employ a little trick here. We redefine the
%    (internal) command \verb*|\Ref | to call |\org@ref| instead of
%    |\ref|. The disadvantgage of this solution is that whenever the
%    derfinition of |\Ref| changes, this definition needs to be updated
%    as well.
%    \begin{macrocode}
      \expandafter\def\csname Ref \endcsname#1{%
        \protected@edef\@tempa{\org@ref{#1}}\expandafter\MakeUppercase\@tempa}
      }{}%
    }
\fi
%    \end{macrocode}
%  \end{macro}
%  \end{macro}
%  \end{macro}
%
%  \subsubsection{\pkg{hhline}}
%
%  \begin{macro}{\hhline}
%    Delaying the activation of the shorthand characters has introduced
%    a problem with the \pkg{hhline} package. The reason is that it
%    uses the `:' character which is made active by the french support
%    in \babel. Therefore we need to \emph{reload} the package when
%    the `:' is an active character.
%
%    So at |\begin{document}| we check whether \pkg{hhline} is loaded.
%    \begin{macrocode}
\AtEndOfPackage{%
  \AtBeginDocument{%
    \@ifpackageloaded{hhline}%
%    \end{macrocode}
%    Then we check whether the expansion of |\normal@char:| is not
%    equal to |\relax|.
% \changes{babel~3.8b}{2004/04/19}{added \cs{string} to prevent
%    unwanted expansion of the colon}
%    \begin{macrocode}
      {\expandafter\ifx\csname normal@char\string:\endcsname\relax
       \else
%    \end{macrocode}
%    In that case we simply reload the package. Note that this happens
%    \emph{after} the category code of the @-sign has been changed to
%    other, so we need to temporarily change it to letter again.
%    \begin{macrocode}
         \makeatletter
         \def\@currname{hhline}\input{hhline.sty}\makeatother
       \fi}%
      {}}}
%    \end{macrocode}
%  \end{macro}
%
%  \subsubsection{\pkg{hyperref}}
%
%  \begin{macro}{\pdfstringdefDisableCommands}
% \changes{babel~3.8j}{2008/03/16}{Inform \pkg{hyperref} to use
%    shorthands at system level (PR4006)}
%
%    A number of interworking problems between \pkg{babel} and
%    \pkg{hyperref} are tackled by \pkg{hyperref} itself. The
%    following code was introduced to prevent some annoying warnings
%    but it broke bookmarks. This was quickly fixed in \pkg{hyperref},
%    which essentially made it no-op. However, it will not removed for
%    the moment because \pkg{hyperref} is expecting it.
%    
%    \begin{macrocode}
\AtBeginDocument{%
  \@ifundefined{pdfstringdefDisableCommands}%
    {}%
    {\pdfstringdefDisableCommands{%
       \languageshorthands{system}}%
    }%
}
%    \end{macrocode}
%  \end{macro}
%
%  \subsubsection{\pkg{fancyhdr}}
%
%  \begin{macro}{\FOREIGNLANGUAGE}
%    The package \pkg{fancyhdr} treats the running head and fout lines
%    somewhat differently as the standard classes. A symptom of this is
%    that the command |\foreignlanguage| which \babel\ adds to the
%    marks can end up inside the argument of |\MakeUppercase|. To
%    prevent unexpected results we need to define |\FOREIGNLANGUAGE|
%    here.
% \changes{babel~3.7j}{2003/05/23}{Define \cs{FOREIGNLANGUAGE}
%    unconditionally}
%    \begin{macrocode}
\DeclareRobustCommand{\FOREIGNLANGUAGE}[1]{%
  \lowercase{\foreignlanguage{#1}}}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\substitutefontfamily}
%    The command |\substitutefontfamily| creates an
%    \file{.fd} file on the fly. The first argument is an encoding
%    mnemonic, the second and third arguments are font family names.
%    \changes{babel~3.7j}{2003/06/15}{create file with lowercase name}
%    \begin{macrocode}
\def\substitutefontfamily#1#2#3{%
  \lowercase{\immediate\openout15=#1#2.fd\relax}%
  \immediate\write15{%
    \string\ProvidesFile{#1#2.fd}%
    [\the\year/\two@digits{\the\month}/\two@digits{\the\day}
     \space generated font description file]^^J
    \string\DeclareFontFamily{#1}{#2}{}^^J
    \string\DeclareFontShape{#1}{#2}{m}{n}{<->ssub * #3/m/n}{}^^J
    \string\DeclareFontShape{#1}{#2}{m}{it}{<->ssub * #3/m/it}{}^^J
    \string\DeclareFontShape{#1}{#2}{m}{sl}{<->ssub * #3/m/sl}{}^^J
    \string\DeclareFontShape{#1}{#2}{m}{sc}{<->ssub * #3/m/sc}{}^^J
    \string\DeclareFontShape{#1}{#2}{b}{n}{<->ssub * #3/bx/n}{}^^J
    \string\DeclareFontShape{#1}{#2}{b}{it}{<->ssub * #3/bx/it}{}^^J
    \string\DeclareFontShape{#1}{#2}{b}{sl}{<->ssub * #3/bx/sl}{}^^J
    \string\DeclareFontShape{#1}{#2}{b}{sc}{<->ssub * #3/bx/sc}{}^^J
    }%
  \closeout15
  }
%    \end{macrocode}
%    This command should only be used in the preamble of a document.
%    \begin{macrocode}
\@onlypreamble\substitutefontfamily
%    \end{macrocode}
%  \end{macro}
%
%  \subsection{Encoding issues}
%
%  Because documents may use non-ASCII font encodings, we make sure
%  that the logos of \TeX\ and \LaTeX\ always come out in the right
%  encoding. There is a list of non-ASCII encodings. Unfortunately,
%  \textsf{fontenc} deletes its package options, so we must guess
%  which encodings has been loaded by traversing |\@filelist| to
%  search for \m{enc}|enc.def|. If a non-ASCII has been loaded, we
%  define versions of |\TeX| and |\LaTeX| for them using
%  |\ensureascii|. The default ASCII encoding is set, too (in reverse
%  order): the ``main'' encoding (when the document begins), the last
%  loaded, or |OT1|.
%
%  \begin{macro}{\ensureascii}
% \changes{babel~3.9i}{2014/02/14}{Macro added, to replace
%    \cs{textlatin} and friends}
% \changes{babel~3.9j}{2014/03/17}{Moved mispaced code - it should be
%    executed only with LaTeX}
%    \begin{macrocode}
\newcommand\BabelNonASCII{LGR,X2,OT2,OT3,OT6,LHE,LWN,LMA,LMC,LMS,LMU,}
\let\org@TeX\TeX
\let\org@LaTeX\LaTeX
\let\ensureascii\@firstofone
\AtBeginDocument{%
  \in@false
  \bbl@loopx\bbl@tempa\BabelNonASCII{% is there a non-ascii enc?
    \ifin@\else
      \edef\bbl@tempb{{,\bbl@tempa enc.def,}{,\@filelist,}}%
      \lowercase\expandafter{\expandafter\in@\bbl@tempb}%
    \fi}
  \ifin@ % if a non-ascii has been loaded
    \def\ensureascii#1{{\fontencoding{OT1}\selectfont#1}}%
    \DeclareTextCommandDefault{\TeX}{\org@TeX}%
    \DeclareTextCommandDefault{\LaTeX}{\org@LaTeX}%
    \def\bbl@tempb#1\@@{\uppercase{\bbl@tempc#1}ENC.DEF\@empty\@@}%
    \def\bbl@tempc#1ENC.DEF#2\@@{%
      \ifx\@empty#2\else
        \@ifundefined{T@#1}% 
          {}%
          {\@expandtwoargs\in@{,#1,}{,\BabelNonASCII,}%
           \ifin@
             \DeclareTextCommand{\TeX}{#1}{\ensureascii{\org@TeX}}%
             \DeclareTextCommand{\LaTeX}{#1}{\ensureascii{\org@LaTeX}}%
           \else
             \def\ensureascii##1{{\fontencoding{#1}\selectfont##1}}%
           \fi}%
      \fi}%
    \bbl@loopx\bbl@tempa\@filelist{\expandafter\bbl@tempb\bbl@tempa\@@}%
    \@expandtwoargs\in@{,\cf@encoding,}{,\BabelNonASCII,}%
    \ifin@\else
      \edef\ensureascii#1{{%
        \noexpand\fontencoding{\cf@encoding}\noexpand\selectfont#1}}%
    \fi
  \fi}
%    \end{macrocode}
%  \end{macro}
%
%  Now comes the old deprecated stuff (with a little change in 3.9l,
%  for \textsf{fontspec}).  The first thing we need to do is to
%  determine, at |\begin{document}|, which latin fontencoding to use.
%
%  \begin{macro}{\latinencoding}
% \changes{babel~3.6i}{1997/03/15}{Macro added, moved from
%    \file{.ldf} files}
%    When text is being typeset in an encoding other than `latin'
%    (\texttt{OT1} or \texttt{T1}), it would be nice to still have
%    Roman numerals come out in the Latin encoding.
%    So we first assume that the current encoding at the end
%    of processing the package is the Latin encoding.
%    \begin{macrocode}
\AtEndOfPackage{\edef\latinencoding{\cf@encoding}}
%    \end{macrocode}
%    But this might be overruled with a later loading of the package
%    \pkg{fontenc}. Therefore we check at the execution of
%    |\begin{document}| whether it was loaded with the \Lopt{T1}
%    option. The normal way to do this (using |\@ifpackageloaded|) is
%    disabled for this package. Now we have to revert to parsing the
%    internal macro |\@filelist| which contains all the filenames
%    loaded.
% \changes{babel~3.6k}{1999/03/15}{Use T1 encoding when it is a known
%    encoding}
% \changes{babel~3.6m}{1999/04/06}{Can't use \cs{@ifpackageloaded}
%    need to parse \cs{@filelist}}
% \changes{babel~3.6n}{1999/04/07}{moved checking for fontenc right to
%    the top of \file{babel.sty}}
% \changes{babel~3.6n}{1999/04/07}{Added a check for `manual' selection
%    of \texttt{T1} encoding, without loading \pkg{fontenc}}
% \changes{babel~3.6q}{1999/04/12}{Better solution than parsing
%    \cs{@filelist}, use \cs{@ifl@aded}}
% \changes{babel~3.6u}{1999/04/20}{Moved this code to
%    \file{babel.def}}
% \changes{babel~3.9l}{2014/08/02}{fontspec used to set
%    \cs{latinencoding} to EUx, but now it doesn't. So,it's done here.}
%    \begin{macrocode}
\AtBeginDocument{%
  \@ifpackageloaded{fontspec}%
    {\xdef\latinencoding{EU\ifcase\bbl@engine\or2\or1\fi}}%
    {\gdef\latinencoding{OT1}%
     \ifx\cf@encoding\bbl@t@one
       \xdef\latinencoding{\bbl@t@one}%
     \else
       \@ifl@aded{def}{t1enc}{\xdef\latinencoding{\bbl@t@one}}{}%
     \fi}}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\latintext}
% \changes{babel~3.6i}{1997/03/15}{Macro added, moved from
%    \file{.ldf} files}
%    Then we can define the command |\latintext| which is a
%    declarative switch to a latin font-encoding. Usage of this macro
%    is deprecated.
%    \begin{macrocode}
\DeclareRobustCommand{\latintext}{%
  \fontencoding{\latinencoding}\selectfont
  \def\encodingdefault{\latinencoding}}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\textlatin}
% \changes{babel~3.6i}{1997/03/15}{Macro added, moved from
%    \file{.ldf} files}
% \changes{babel~3.7j}{2003/03/19}{added \cs{leavevmode} to prevent a
%    paragraph starting \emph{inside} the group}
% \changes{babel~3.7k}{2003/10/12}{Use \cs{DeclareTextFontComand}}
%    This command takes an argument which is then typeset using the
%    requested font encoding. In order to avoid many encoding switches
%    it operates in a local scope.
%    \begin{macrocode}
\ifx\@undefined\DeclareTextFontCommand
  \DeclareRobustCommand{\textlatin}[1]{\leavevmode{\latintext #1}}
\else
  \DeclareTextFontCommand{\textlatin}{\latintext}
\fi
%    \end{macrocode}
% \end{macro}
%
% \subsection{Local Language Configuration}
%
%  \begin{macro}{\loadlocalcfg}
%    At some sites it may be necessary to add site-specific actions to
%    a language definition file. This can be done by creating a file
%    with the same name as the language definition file, but with the
%    extension \file{.cfg}. For instance the file \file{norsk.cfg}
%    will be loaded when the language definition file \file{norsk.ldf}
%    is loaded.
%
% \changes{babel~3.5d}{1995/06/22}{Added macro}
%    For plain-based formats we don't want to override the definition
%    of |\loadlocalcfg| from \file{plain.def}.
%    \begin{macrocode}
\ifx\loadlocalcfg\@undefined
  \@ifpackagewith{babel}{noconfigs}%
    {\let\loadlocalcfg\@gobble}%
    {\def\loadlocalcfg#1{%
      \InputIfFileExists{#1.cfg}%
        {\typeout{*************************************^^J%
                       * Local config file #1.cfg used^^J%
                       *}}%
        \@empty}}
\fi
%    \end{macrocode}
%    Just to be compatible with \LaTeX$\:$2.09 we add a few more lines
%    of code:
%    \begin{macrocode}
\ifx\@unexpandable@protect\@undefined
  \def\@unexpandable@protect{\noexpand\protect\noexpand}
  \long\def\protected@write#1#2#3{%
    \begingroup
      \let\thepage\relax
      #2%
      \let\protect\@unexpandable@protect
      \edef\reserved@a{\write#1{#3}}%
      \reserved@a
    \endgroup
    \if@nobreak\ifvmode\nobreak\fi\fi}
\fi
%</core>
%    \end{macrocode}%
%    \end{macro}
%
%    \section{Internationalizing \LaTeX{} 2.09}
%
%    Now that we're sure that the code is seen by \LaTeX\ only, we
%    have to find out what the main (primary) document style is
%    because we want to redefine some macros.  This is only necessary
%    for releases of \LaTeX\ dated before December~1991. Therefore
%    this part of the code can optionally be included in
%    \file{babel.def} by specifying the \texttt{docstrip} option
%    \texttt{names}.
%
%    The standard styles can be distinguished by checking whether some
%    macros are defined. In table~\ref{styles} an overview is given of
%    the macros that can be used for this purpose.
%  \begin{table}[htb]
%  \begin{center}
% \DeleteShortVerb{\|}
%  \begin{tabular}{|lcp{8cm}|}
%   \hline
%   article         & : & both the \verb+\chapter+ and \verb+\opening+
%                         macros are undefined\\
%   report and book & : & the \verb+\chapter+ macro is defined and
%                         the \verb+\opening+ is undefined\\
%   letter          & : & the \verb+\chapter+ macro is undefined and
%                         the \verb+\opening+ is defined\\
%   \hline
%  \end{tabular}
% \caption{How to determine the main document style}\label{styles}
% \MakeShortVerb{\|}
%  \end{center}
%  \end{table}
%
%    \noindent The macros that have to be redefined for the
%    \texttt{report} and \texttt{book} document styles happen to be
%    the same, so there is no need to distinguish between those two
%    styles.
%
%  \begin{macro}{\doc@style}
%    First a parameter |\doc@style| is defined to identify the current
%    document style. This parameter might have been defined by a
%    document style that already uses macros instead of hard-wired
%    texts, such as \file{artikel1.sty}~\cite{BEP}, so the existence of
%    |\doc@style| is checked. If this macro is undefined, i.\,e., if
%    the document style is unknown and could therefore contain
%    hard-wired texts, |\doc@style| is defined to the default
%    value~`0'.
% \changes{babel~3.0d}{1991/10/29}{Removed use of \cs{@ifundefined}}
%    \begin{macrocode}
%<*names>
\ifx\@undefined\doc@style
  \def\doc@style{0}%
%    \end{macrocode}
%    This parameter is defined in the following \texttt{if}
%    construction (see table~\ref{styles}):
%
%    \begin{macrocode}
  \ifx\@undefined\opening
    \ifx\@undefined\chapter
      \def\doc@style{1}%
    \else
      \def\doc@style{2}%
    \fi
  \else
    \def\doc@style{3}%
  \fi%
\fi%
%    \end{macrocode}
%  \end{macro}
%
% \changes{babel~3.1}{1991/11/05}{Removed definition of
%    \cs{if@restonecol}}
%
%    Now here comes the real work: we start to redefine things and
%    replace hard-wired texts by macros. These redefinitions should be
%    carried out conditionally, in case it has already been done.
%
%    For the \texttt{figure} and \texttt{table} environments we have
%    in all styles:
%    \begin{macrocode}
\@ifundefined{figurename}{\def\fnum@figure{\figurename{} \thefigure}}{}
\@ifundefined{tablename}{\def\fnum@table{\tablename{} \thetable}}{}
%    \end{macrocode}
%
%    The rest of the macros have to be treated differently for each
%    style.  When |\doc@style| still has its default value nothing
%    needs to be done.
%    \begin{macrocode}
\ifcase \doc@style\relax
\or
%    \end{macrocode}
%
%    This means that \file{babel.def} is read after the
%    \texttt{article} style, where no |\chapter| and |\opening|
%    commands are defined\footnote{A fact that was pointed out to me
%    by Nico Poppelier and was already used in Piet van Oostrum's
%    document style option~\texttt{nl}.}.
%
%    First we have the |\tableofcontents|,
%    |\listoffigures| and |\listoftables|:
%    \begin{macrocode}
\@ifundefined{contentsname}%
    {\def\tableofcontents{\section*{\contentsname\@mkboth
          {\uppercase{\contentsname}}{\uppercase{\contentsname}}}%
      \@starttoc{toc}}}{}
\@ifundefined{listfigurename}%
    {\def\listoffigures{\section*{\listfigurename\@mkboth
          {\uppercase{\listfigurename}}{\uppercase{\listfigurename}}}%
     \@starttoc{lof}}}{}
\@ifundefined{listtablename}%
    {\def\listoftables{\section*{\listtablename\@mkboth
          {\uppercase{\listtablename}}{\uppercase{\listtablename}}}%
      \@starttoc{lot}}}{}
%    \end{macrocode}
%
% Then the |\thebibliography| and |\theindex| environments.
%
%    \begin{macrocode}
\@ifundefined{refname}%
    {\def\thebibliography#1{\section*{\refname
      \@mkboth{\uppercase{\refname}}{\uppercase{\refname}}}%
      \list{[\arabic{enumi}]}{\settowidth\labelwidth{[#1]}%
        \leftmargin\labelwidth
        \advance\leftmargin\labelsep
        \usecounter{enumi}}%
        \def\newblock{\hskip.11em plus.33em minus.07em}%
        \sloppy\clubpenalty4000\widowpenalty\clubpenalty
        \sfcode`\.=1000\relax}}{}
\@ifundefined{indexname}%
    {\def\theindex{\@restonecoltrue\if@twocolumn\@restonecolfalse\fi
     \columnseprule \z@
     \columnsep 35pt\twocolumn[\section*{\indexname}]%
       \@mkboth{\uppercase{\indexname}}{\uppercase{\indexname}}%
       \thispagestyle{plain}%
       \parskip\z@ plus.3pt\parindent\z@\let\item\@idxitem}}{}
%    \end{macrocode}
%
% The |abstract| environment:
%
%    \begin{macrocode}
\@ifundefined{abstractname}%
    {\def\abstract{\if@twocolumn
    \section*{\abstractname}%
    \else \small
    \begin{center}%
    {\bf \abstractname\vspace{-.5em}\vspace{\z@}}%
    \end{center}%
    \quotation
    \fi}}{}
%    \end{macrocode}
%
% And last but not least, the macro |\part|:
%
%    \begin{macrocode}
\@ifundefined{partname}%
{\def\@part[#1]#2{\ifnum \c@secnumdepth >\m@ne
        \refstepcounter{part}%
        \addcontentsline{toc}{part}{\thepart
        \hspace{1em}#1}\else
      \addcontentsline{toc}{part}{#1}\fi
   {\parindent\z@ \raggedright
    \ifnum \c@secnumdepth >\m@ne
      \Large \bf \partname{} \thepart
      \par \nobreak
    \fi
    \huge \bf
    #2\markboth{}{}\par}%
    \nobreak
    \vskip 3ex\@afterheading}%
}{}
%    \end{macrocode}
%
%    This is all that needs to be done for the \texttt{article} style.
%
%    \begin{macrocode}
\or
%    \end{macrocode}
%
%    The next case is formed by the two styles \texttt{book} and
%    \texttt{report}.  Basically we have to do the same as for the
%    \texttt{article} style, except now we must also change the
%    |\chapter| command.
%
%    The tables of contents, figures and tables:
%    \begin{macrocode}
\@ifundefined{contentsname}%
    {\def\tableofcontents{\@restonecolfalse
      \if@twocolumn\@restonecoltrue\onecolumn
      \fi\chapter*{\contentsname\@mkboth
          {\uppercase{\contentsname}}{\uppercase{\contentsname}}}%
      \@starttoc{toc}%
      \csname if@restonecol\endcsname\twocolumn
      \csname fi\endcsname}}{}
\@ifundefined{listfigurename}%
    {\def\listoffigures{\@restonecolfalse
      \if@twocolumn\@restonecoltrue\onecolumn
      \fi\chapter*{\listfigurename\@mkboth
          {\uppercase{\listfigurename}}{\uppercase{\listfigurename}}}%
      \@starttoc{lof}%
      \csname if@restonecol\endcsname\twocolumn
      \csname fi\endcsname}}{}
\@ifundefined{listtablename}%
    {\def\listoftables{\@restonecolfalse
      \if@twocolumn\@restonecoltrue\onecolumn
      \fi\chapter*{\listtablename\@mkboth
          {\uppercase{\listtablename}}{\uppercase{\listtablename}}}%
      \@starttoc{lot}%
      \csname if@restonecol\endcsname\twocolumn
      \csname fi\endcsname}}{}
%    \end{macrocode}
%
%    Again, the |bibliography| and |index| environments; notice that
%    in this case we use |\bibname| instead of |\refname| as in the
%    definitions for the \texttt{article} style.  The reason for this
%    is that in the \texttt{article} document style the term
%    `References' is used in the definition of |\thebibliography|. In
%    the \texttt{report} and \texttt{book} document styles the term
%    `Bibliography' is used.
%    \begin{macrocode}
\@ifundefined{bibname}%
    {\def\thebibliography#1{\chapter*{\bibname
     \@mkboth{\uppercase{\bibname}}{\uppercase{\bibname}}}%
     \list{[\arabic{enumi}]}{\settowidth\labelwidth{[#1]}%
     \leftmargin\labelwidth \advance\leftmargin\labelsep
     \usecounter{enumi}}%
     \def\newblock{\hskip.11em plus.33em minus.07em}%
     \sloppy\clubpenalty4000\widowpenalty\clubpenalty
     \sfcode`\.=1000\relax}}{}
\@ifundefined{indexname}%
    {\def\theindex{\@restonecoltrue\if@twocolumn\@restonecolfalse\fi
    \columnseprule \z@
    \columnsep 35pt\twocolumn[\@makeschapterhead{\indexname}]%
      \@mkboth{\uppercase{\indexname}}{\uppercase{\indexname}}%
    \thispagestyle{plain}%
    \parskip\z@ plus.3pt\parindent\z@ \let\item\@idxitem}}{}
%    \end{macrocode}
%
% Here is the |abstract| environment:
%    \begin{macrocode}
\@ifundefined{abstractname}%
    {\def\abstract{\titlepage
    \null\vfil
    \begin{center}%
    {\bf \abstractname}%
    \end{center}}}{}
%    \end{macrocode}
%
%     And last but not least the |\chapter|, |\appendix| and
%    |\part| macros.
%    \begin{macrocode}
\@ifundefined{chaptername}{\def\@chapapp{\chaptername}}{}
%
\@ifundefined{appendixname}%
    {\def\appendix{\par
      \setcounter{chapter}{0}%
      \setcounter{section}{0}%
      \def\@chapapp{\appendixname}%
      \def\thechapter{\Alph{chapter}}}}{}
%
\@ifundefined{partname}%
    {\def\@part[#1]#2{\ifnum \c@secnumdepth >-2\relax
            \refstepcounter{part}%
            \addcontentsline{toc}{part}{\thepart
            \hspace{1em}#1}\else
            \addcontentsline{toc}{part}{#1}\fi
       \markboth{}{}%
       {\centering
        \ifnum \c@secnumdepth >-2\relax
          \huge\bf \partname{} \thepart
        \par
        \vskip 20pt \fi
        \Huge \bf
        #1\par}\@endpart}}{}%
%    \end{macrocode}
%
%    \begin{macrocode}
\or
%    \end{macrocode}
%
%    Now we address the case where \file{babel.def} is read after the
%    \texttt{letter} style. The \texttt{letter} document style
%    defines the macro |\opening| and some other macros that are
%    specific to \texttt{letter}. This means that we have to redefine
%    other macros, compared to the previous two cases.
%
%    First two macros for the material at the end of a letter, the
%    |\cc| and |\encl| macros.
%    \begin{macrocode}
\@ifundefined{ccname}%
    {\def\cc#1{\par\noindent
     \parbox[t]{\textwidth}%
     {\@hangfrom{\rm \ccname : }\ignorespaces #1\strut}\par}}{}
\@ifundefined{enclname}%
    {\def\encl#1{\par\noindent
     \parbox[t]{\textwidth}%
     {\@hangfrom{\rm \enclname : }\ignorespaces #1\strut}\par}}{}
%    \end{macrocode}
%
%    The last thing we have to do here is to redefine the
%    \texttt{headings} pagestyle:
% \changes{babel~3.3}{1993/07/11}{\cs{headpagename} should be
%    \cs{pagename}}
%    \begin{macrocode}
\@ifundefined{headtoname}%
  {\def\ps@headings{%
     \def\@oddhead{\sl \headtoname{} \ignorespaces\toname \hfil
                      \@date \hfil \pagename{} \thepage}%
     \def\@oddfoot{}}}{}
%    \end{macrocode}
%
%    This was the last of the four standard document styles, so if
%    |\doc@style| has another value we do nothing and just close the
%    \texttt{if} construction.
%    \begin{macrocode}
\fi
%</names>
%    \end{macrocode}
%    Here ends the code that can be optionally included when a version
%    of \LaTeX\ is in use that is dated \emph{before} December~1991.
%
%
%    We also need to redefine a number of commands to ensure that the
%    right font encoding is used, but this can't be done before
%    \file{babel.def} is loaded.
% \changes{babel~3.6o}{1999/04/07}{Moved the rest of the font encoding
%    related definitions to their original place}
%
% \section{Multiple languages}
%
%    Plain \TeX\ version~3.0 provides the primitive |\language| that
%    is used to store the current language. When used with a pre-3.0
%    version this function has to be implemented by allocating a
%    counter.
%    \begin{macrocode}
%<*kernel>
<@Make sure ProvidesFile is defined@>
\ProvidesFile{switch.def}[<@date@> <@version@> Babel switching mechanism]
<@Load macros for plain if not LaTeX@>
<@Define core switching macros@>
%    \end{macrocode}
%
%  \begin{macro}{\adddialect}
%    The macro |\adddialect| can be used to add the name of a dialect
%    or variant language, for which an already defined hyphenation
%    table can be used.
% \changes{babel~3.2}{1991/11/11}{Added \cs{relax}}
%    \begin{macrocode}
\def\bbl@version{<@version@>}
\def\bbl@date{<@date@>}
\def\adddialect#1#2{%
  \global\chardef#1#2\relax
  \bbl@usehooks{adddialect}{{#1}{#2}}%
  \wlog{\string#1 = a dialect from \string\language#2}}
%    \end{macrocode}
%  \end{macro}
% \changes{babel~3.9a}{2012/09/07}{Added macro}
% \changes{babel~3.9a}{2013/01/23}{New macro to normalize 
%    a macro (eg, \cs{languagename}) to lowercase if necessary}
%
%    |\bbl@iflanguage| executes code only of the language
%    exists. Otherwise raises and error.
%
%    The argument of |\bbl@fixname| has to be a macro name, as it may get
%    ``fixed'' if casing (lc/uc) is wrong. It's intented to fix a
%    long-standing bug when |\foreignlanguage| and the like appear in
%    a |\MakeXXXcase|. However, a lowercase form is not imposed to
%    improve backward compatibility (perhaps you defined a language
%    named |MYLANG|, but unfortunately mixed case names cannot be
%    trapped).
%    \begin{macrocode}
\def\bbl@fixname#1{%
  \begingroup
    \def\bbl@tempe{l@}%
    \edef\bbl@tempd{\noexpand\@ifundefined{\noexpand\bbl@tempe#1}}%
    \bbl@tempd
      {\lowercase\expandafter{\bbl@tempd}%
         {\uppercase\expandafter{\bbl@tempd}%
           \@empty
           {\edef\bbl@tempd{\def\noexpand#1{#1}}%
            \uppercase\expandafter{\bbl@tempd}}}%
         {\edef\bbl@tempd{\def\noexpand#1{#1}}%
          \lowercase\expandafter{\bbl@tempd}}}%
      \@empty
    \edef\bbl@tempd{\endgroup\def\noexpand#1{#1}}%
  \bbl@tempd}
\def\bbl@iflanguage#1{%
  \@ifundefined{l@#1}{\@nolanerr{#1}\@gobble}\@firstofone}
%    \end{macrocode}
%
%  \begin{macro}{\iflanguage}
%    Users might want to test (in a private package for instance)
%    which language is currently active. For this we provide a test
%    macro, |\iflanguage|, that has three arguments.  It checks
%    whether the first argument is a known language. If so, it
%    compares the first argument with the value of |\language|. Then,
%    depending on the result of the comparison, it executes either the
%    second or the third argument.
% \changes{babel~3.2}{1991/11/11}{Rephrased \cs{ifnum} test}
% \changes{babel~3.7a}{1998/06/10}{Now evaluate the \cs{ifnum} test
%    \emph{after} the \cs{fi} from the \cs{ifx} test and use
%    \cs{@firstoftwo} and \cs{@secondoftwo}}
%    \begin{macrocode}
\def\iflanguage#1{%
  \bbl@iflanguage{#1}{%
    \ifnum\csname l@#1\endcsname=\language
      \expandafter\@firstoftwo
    \else
      \expandafter\@secondoftwo
    \fi}}
%    \end{macrocode}
%  \end{macro}
%
%   \subsection{Selecting the language}
%
%  \begin{macro}{\selectlanguage}
%    The macro |\selectlanguage| checks whether the language is
%    already defined before it performs its actual task, which is to
%    update |\language| and activate language-specific definitions.
%
%    To allow the call of |\selectlanguage| either with a control
%    sequence name or with a simple string as argument, we have to use
%    a trick to delete the optional escape character.
%
%    To convert a control sequence to a string, we use the |\string|
%    primitive.  Next we have to look at the first character of this
%    string and compare it with the escape character.  Because this
%    escape character can be changed by setting the internal integer
%    |\escapechar| to a character number, we have to compare this
%    number with the character of the string.  To do this we have to
%    use \TeX's backquote notation to specify the character as a
%    number.
%
%    If the first character of the |\string|'ed argument is the
%    current escape character, the comparison has stripped this
%    character and the rest in the `then' part consists of the rest of
%    the control sequence name.  Otherwise we know that either the
%    argument is not a control sequence or |\escapechar| is set to a
%    value outside of the character range~$0$--$255$.
%
%    If the user gives an empty argument, we provide a default
%    argument for |\string|.  This argument should expand to nothing.
%
% \changes{babel~3.0c}{1991/06/06}{Made \cs{selectlanguage}
%    robust}
% \changes{babel~3.2}{1991/11/11}{Modified to allow arguments that
%    start with an escape character}
% \changes{babel~3.2a}{1991/11/17}{Simplified the modification to
%    allow the use in a \cs{write} command}
% \changes{babel~3.5b}{1995/05/13}{Store the name of the current
%    language in a control sequence instead of passing the whole macro
%    construct to strip the escape character in the argument of
%    \cs{selectlanguage }.}
% \changes{babel~3.5f}{1995/11/16}{Moved check for escape character
%    one level down in the expansion}
% \changes{babel~3.9a}{2012/11/16}{\cs{bbl@select@type} keep tracks of
%    the selection method: 0 is select, 1 is foreign}
%    \begin{macrocode}
\let\bbl@select@type\z@
\edef\selectlanguage{%
  \noexpand\protect
  \expandafter\noexpand\csname selectlanguage \endcsname}
%    \end{macrocode}
%    Because the command |\selectlanguage| could be used in a moving
%    argument it expands to \verb*=\protect\selectlanguage =.
%    Therefore, we have to make sure that a macro |\protect| exists.
%    If it doesn't it is |\let| to |\relax|.
%    \begin{macrocode}
\ifx\@undefined\protect\let\protect\relax\fi
%    \end{macrocode}
%    As \LaTeX$\:$2.09 writes to files \textit{expanded} whereas
%    \LaTeXe\ takes care \textit{not} to expand the arguments of
%    |\write| statements we need to be a bit clever about the way we
%    add information to \file{.aux} files. Therefore we introduce the
%    macro |\xstring| which should expand to the right amount of
%    |\string|'s.
%    \begin{macrocode}
\ifx\documentclass\@undefined
  \def\xstring{\string\string\string}
\else
  \let\xstring\string
\fi
%    \end{macrocode}
% \end{macro}
%
% \changes{babel~3.5b}{1995/03/04}{Changed the name of the internal
%    macro to \cs{selectlanguage }.}
% \changes{babel~3.5b}{1995/03/05}{Added an extra level of expansion to
%    separate the switching mechanism from writing to aux files}
% \changes{babel~3.7f}{2000/09/25}{Use \cs{aftergroup} to keep the
%    language grouping correct in auxiliary files {PR3091}}
%    Since version 3.5 \babel\ writes entries to the auxiliary files in
%    order to typeset table of contents etc. in the correct language
%    environment.
%  \begin{macro}{\bbl@pop@language}
%    \emph{But} when the language change happens \emph{inside} a group
%    the end of the group doesn't write anything to the auxiliary
%    files. Therefore we need \TeX's |aftergroup| mechanism to help
%    us. The command |\aftergroup| stores the token immediately
%    following it to be executed when the current group is closed. So
%    we define a temporary control sequence |\bbl@pop@language| to be
%    executed at the end of the group. It calls |\bbl@set@language|
%    with the name of the current language as its argument.
%
% \changes{babel~3.7j}{2003/03/18}{Introduce the language stack
%    mechanism}
%  \begin{macro}{\bbl@language@stack}
%    The previous solution works for one level of nesting groups, but
%    as soon as more levels are used it is no longer adequate. For
%    that case we need to keep track of the nested languages using a
%    stack mechanism. This stack is called |\bbl@language@stack| and
%    initially empty.
%    \begin{macrocode}
\def\bbl@language@stack{}
%    \end{macrocode}
%    When using a stack we need a mechanism to push an element on the
%    stack and to retrieve the information afterwards.
%  \begin{macro}{\bbl@push@language}
%  \begin{macro}{\bbl@pop@language}
%    The stack is simply a list of languagenames, separated with a `+'
%    sign; the push function can be simple:
%    \begin{macrocode}
\def\bbl@push@language{%
  \xdef\bbl@language@stack{\languagename+\bbl@language@stack}}
%    \end{macrocode}
%    Retrieving information from the stack is a little bit less simple,
%    as we need to remove the element from the stack while storing it
%    in the macro |\languagename|. For this we first define a helper function.
%  \begin{macro}{\bbl@pop@lang}
%    This macro stores its first element (which is delimited by the
%    `+'-sign) in |\languagename| and stores the rest of the string
%    (delimited by `-') in its third argument.
%    \begin{macrocode}
\def\bbl@pop@lang#1+#2-#3{%
  \edef\languagename{#1}\xdef#3{#2}}
%    \end{macrocode}
%  \end{macro}
%    The reason for the somewhat weird arrangement of arguments to the
%    helper function is the fact it is called in the following way.
%    This means that before |\bbl@pop@lang| is executed \TeX\ first
%    \emph{expands} the stack, stored in |\bbl@language@stack|. The
%    result of that is that the argument string of |\bbl@pop@lang|
%    contains one or more language names, each followed by a `+'-sign
%    (zero language names won't occur as this macro will only be
%    called after something has been pushed on the stack) followed by
%    the `-'-sign and finally the reference to the stack.
%    \begin{macrocode}
\def\bbl@pop@language{%
  \expandafter\bbl@pop@lang\bbl@language@stack-\bbl@language@stack
  \expandafter\bbl@set@language\expandafter{\languagename}}
%    \end{macrocode}
%    Once the name of the previous language is retrieved from the stack,
%    it is fed to |\bbl@set@language| to do the actual work of
%    switching everything that needs switching.
%  \end{macro}
%  \end{macro}
%  \end{macro}
%
% \changes{babel~3.7j}{2003/03/18}{Now use the language stack mechanism}
%    \begin{macrocode}
\expandafter\def\csname selectlanguage \endcsname#1{%
  \ifnum\bbl@hymapsel=\@cclv\let\bbl@hymapsel\tw@\fi
  \bbl@push@language
  \aftergroup\bbl@pop@language
  \bbl@set@language{#1}}
%    \end{macrocode}
% \changes{babel~3.7m}{2003/11/12}{Removed the superfluous empty
%    definition of \cs{bbl@pop@language}}
%  \end{macro}
%
%  \begin{macro}{\bbl@set@language}
%    \changes{babel~3.7f}{2000/09/25}{Macro \cs{bbl@set@language}
%    introduced}
% 
%    The macro |\bbl@set@language| takes care of switching the
%    language environment \emph{and} of writing entries on the
%    auxiliary files.  For historial reasons, language names can be
%    either |language| of |\language|. To catch either form a trick is
%    used, but unfortunately as a side effect the catcodes of letters
%    in |\languagename| are not well defined. The list of auxiliary
%    files can be extended by redefining |\BabelContentsFiles|, but
%    make sure they are loaded inside a group (as |aux|, |toc|,
%    |lof|, and |lot| do) or the last language of the document will
%    remain active afterwards.
%
%    We also write a command to change the current language in the
%    auxiliary files.
% \changes{babel~3.5a}{1995/02/17}{Write the language change to the
%    auxiliary files}
% \changes{babel~3.9a}{2012/09/09}{Added hook}
% \changes{babel~3.9a}{2012/11/07}{Use a loop for contents files, with
%    the help of \cs{BabelContentsFiles}}
% \changes{babel~3.9a}{2013/03/08}{Don't write to aux if language is
%    unknown}
% \changes{babel~3.9h}{2013/11/20}{Error with a more helpful text }
%    \begin{macrocode}
\def\BabelContentsFiles{toc,lof,lot}
\def\bbl@set@language#1{%
  \edef\languagename{%
    \ifnum\escapechar=\expandafter`\string#1\@empty
    \else\string#1\@empty\fi}%
  \select@language{\languagename}%
  \expandafter\ifx\csname date\languagename\endcsname\relax\else
    \if@filesw
      \protected@write\@auxout{}{\string\select@language{\languagename}}%
      \bbl@for\bbl@tempa\BabelContentsFiles{%
        \addtocontents{\bbl@tempa}{\xstring\select@language{\languagename}}}%
      \bbl@usehooks{write}{}%
    \fi
  \fi}
\def\select@language#1{%
  \ifnum\bbl@hymapsel=\@cclv\chardef\bbl@hymapsel4\relax\fi
  \edef\languagename{#1}%
  \bbl@fixname\languagename
  \bbl@iflanguage\languagename{%
    \expandafter\ifx\csname date\languagename\endcsname\relax
      \bbl@error
        {Unknown language `#1'. Either you have\\%
         misspelled its name, it has not been installed,\\%
         or you requested it in a previous run. Fix its name,\\%
         install it or just rerun the file, respectively}%
        {You may proceed, but expect unexpected results}%
    \else
      \let\bbl@select@type\z@
      \expandafter\bbl@switch\expandafter{\languagename}%
    \fi}}
% A bit of optimization:
\def\select@language@x#1{%
  \ifcase\bbl@select@type
    \bbl@ifsamestring\languagename{#1}{}{\select@language{#1}}%
  \else
    \select@language{#1}%
  \fi}
%    \end{macrocode}
%  \end{macro}
%
%    First, check if the user asks for a known language. If so,
%    update the value of |\language| and call |\originalTeX|
%    to bring \TeX\ in a certain pre-defined state.
% \changes{babel~3.0a}{1991/05/29}{Added \cs{@bsphack} and
%    \cs{@esphack}}
% \changes{babel~3.0d}{1991/08/08}{Removed superfluous
%    \cs{expandafter}}
% \changes{babel~3.0d}{1991/10/07}{Removed space hacks and use of
%    \cs{@ifundefined}}
% \changes{babel~3.2a}{1991/11/17}{Added \cs{relax} as first command
%    to stop an expansion if \cs{protect} is empty}
% \changes{babel~3.6a}{1996/11/07}{Check for the existence of
%    \cs{date...} instead of \cs{l@...}}
% \changes{babel~3.7m}{2003/11/16}{Check for the existence of both
%    \cs{l@...} and \cs{date...}}
% \changes{babel~3.8l}{2008/07/06}{Use \cs{bbl@patterns}}
% \changes{babel~3.9a}{2012/07/27}{Moved \cs{bbl@patterns} to the
%    correct place, after setting the extras for the current
%    language}
% \changes{babel~3.9a}{2012/08/01}{Created \cs{bbl@swith} with code
%    shared by \cs{select@language} and \cs{foreing@language}}
%    \begin{macrocode}
%    \end{macrocode}
%    The name of the language is stored in the control sequence
%    |\languagename|.
%
%    Then we have to \emph{re}define |\originalTeX| to compensate for
%    the things that have been activated.  To save memory space for
%    the macro definition of |\originalTeX|, we construct the control
%    sequence name for the |\noextras|\langvar\ command at definition
%    time by expanding the |\csname| primitive.
%
%    Now activate the language-specific definitions. This is done by
%    constructing the names of three macros by concatenating three
%    words with the argument of |\selectlanguage|, and calling these
%    macros. \nb{What if \cs{hyphenation} was used in |extras|? Patch
%    temply set@hyphenmins and hyphenation. It can be done in hooks if
%    necessary.}
% \changes{babel~3.5b}{1995/05/13}{Separated the setting of the
%    hyphenmin values}%
% \changes{babel~3.9c}{2013/04/08}{Removed an extra empty line}
%
%    The switching of the values of |\lefthyphenmin| and
%    |\righthyphenmin| is somewhat different. First we save their
%    current values, then we check if |\|\langvar|hyphenmins| is
%    defined. If it is not, we set default values (2 and 3), otherwise
%    the values in |\|\langvar|hyphenmins| will be used.
% \changes{babel~3.5b}{1995/06/05}{Addedd default setting of hyphenmin
%    parameters}
% \changes{babel~3.9a}{2012/08/01}{Adddd \cs{bbl@iflanguagename} and
%   \cs{select@language@x}, which is no-op if the language is the same}
% \changes{babel~3.9a}{2013/01/23}{\cs{select@language} sets 
%   \textsc{languagename} so that it has the correct value in the aux
%   file (eg, shorthand expansion was wrong)}
% \changes{babel~3.0a}{1991/06/06}{Replaced \cs{gdef} with \cs{def}}
% \changes{babel~3.1}{1991/10/31}{\cs{originalTeX} should only be
%    executed once}
% \changes{babel~3.2a}{1991/11/17}{Added three \cs{expandafter}s
%    to save macro space for \cs{originalTeX}}
% \changes{babel~3.2a}{1991/11/20}{Moved definition of
%    \cs{originalTeX} before \cs{extras\langvar}}
% \changes{babel~3.2a}{1991/11/24}{Set \cs{originalTeX} to
%    \cs{empty}, because it should be expandable.}
% \changes{babel~3.6d}{1997/01/07}{set the language shorthands to
%    `none' before switching on the extras}
% \changes{babel~3.9a}{2012/08/14}{Make sure the save counter is reset
%    even if \cs{originalTeX} is used in other contexts}
% \changes{babel~3.9h}{2013/11/29}{Use \cs{def} instead of
%    \cs{renewcommand} for \cs{BabelLower}}
% \changes{babel~3.9i}{2014/03/04}{Added `afterreset' hook}
%    \begin{macrocode}
\def\bbl@switch#1{%
  \originalTeX
  \expandafter\def\expandafter\originalTeX\expandafter{%
    \csname noextras#1\endcsname
    \let\originalTeX\@empty
    \babel@beginsave}%
  \bbl@usehooks{afterreset}{}%
  \languageshorthands{none}%
  \ifcase\bbl@select@type
    \csname captions#1\endcsname
    \csname date#1\endcsname
  \fi
  \bbl@usehooks{beforeextras}{}%
  \csname extras#1\endcsname\relax
  \bbl@usehooks{afterextras}{}%
  \ifcase\bbl@hymapopt\or
    \def\BabelLower##1##2{\lccode##1=##2\relax}%
    \ifnum\bbl@hymapsel>4\else
      \csname\languagename @bbl@hyphenmap\endcsname
    \fi
    \chardef\bbl@hymapopt\z@
  \else
    \ifnum\bbl@hymapsel>\bbl@hymapopt\else
      \csname\languagename @bbl@hyphenmap\endcsname
    \fi
  \fi
  \global\let\bbl@hymapsel\@cclv
  \bbl@patterns{#1}%
  \babel@savevariable\lefthyphenmin
  \babel@savevariable\righthyphenmin
  \expandafter\ifx\csname #1hyphenmins\endcsname\relax
    \set@hyphenmins\tw@\thr@@\relax
  \else
    \expandafter\expandafter\expandafter\set@hyphenmins
      \csname #1hyphenmins\endcsname\relax
  \fi}
%    \end{macrocode}
%    \begin{macrocode}
\def\bbl@ifsamestring#1#2{%
  \protected@edef\bbl@tempb{#1}%
  \edef\bbl@tempb{\expandafter\strip@prefix\meaning\bbl@tempb}%
  \protected@edef\bbl@tempc{#2}%
  \edef\bbl@tempc{\expandafter\strip@prefix\meaning\bbl@tempc}%
  \ifx\bbl@tempb\bbl@tempc
    \expandafter\@firstoftwo
  \else
    \expandafter\@secondoftwo
  \fi}
%    \end{macrocode}
%
%  \begin{environment}{otherlanguage}
%    The \Lenv{otherlanguage} environment can be used as an
%    alternative to using the |\selectlanguage| declarative
%    command. When you are typesetting a document which mixes
%    left-to-right and right-to-left typesetting you have to use this
%    environment in order to let things work as you expect them to.
%
%    The first thing this environment does is store the name of the
%    language in |\languagename|; it then calls
%    \verb*=\selectlanguage = to switch on everything that is needed for
%    this language The |\ignorespaces| command is necessary to hide
%    the environment when it is entered in horizontal mode.
% \changes{babel~3.5d}{1995/06/22}{environment added}
% \changes{babel~3.5e}{1995/07/07}{changed name}
% \changes{babel~3.7j}{2003/03/18}{rely on \cs{selectlanguage } to
%    keep track of the nesting}
% \changes{babel~3.9a}{2012/07/31}{Removed \cs{originalTeX}}
%    \begin{macrocode}
\long\def\otherlanguage#1{%
  \ifnum\bbl@hymapsel=\@cclv\let\bbl@hymapsel\thr@@\fi
  \csname selectlanguage \endcsname{#1}%
  \ignorespaces}
%    \end{macrocode}
%    The |\endotherlanguage| part of the environment tries to hide
%    itself when it is called in horizontal mode.
%    \begin{macrocode}
\long\def\endotherlanguage{%
  \global\@ignoretrue\ignorespaces}
%    \end{macrocode}
%  \end{environment}
%
%  \begin{environment}{otherlanguage*}
%    The \Lenv{otherlanguage} environment is meant to be used when a
%    large part of text from a different language needs to be typeset,
%    but without changing the translation of words such as `figure'.
%    This environment makes use of |\foreign@language|.
% \changes{babel~3.5f}{1996/05/29}{environment added}
% \changes{babel~3.6d}{1997/01/07}{Introduced \cs{foreign@language}}
%    \begin{macrocode}
\expandafter\def\csname otherlanguage*\endcsname#1{%
  \ifnum\bbl@hymapsel=\@cclv\chardef\bbl@hymapsel4\relax\fi
  \foreign@language{#1}}
%    \end{macrocode}
%    At the end of the environment we need to switch off the extra
%    definitions. The grouping mechanism of the environment will take
%    care of resetting the correct hyphenation rules and ``extras''.
%    \begin{macrocode} 
\expandafter\let\csname endotherlanguage*\endcsname\relax
%    \end{macrocode}
%  \end{environment}
%
%  \begin{macro}{\foreignlanguage}
%    The |\foreignlanguage| command is another substitute for the
%    |\selectlanguage| command. This command takes two arguments, the
%    first argument is the name of the language to use for typesetting
%    the text specified in the second argument.
%
%    Unlike |\selectlanguage| this command doesn't switch
%    \emph{everything}, it only switches the hyphenation rules and the
%    extra definitions for the language specified. It does this within
%    a group and assumes the |\extras|\langvar\ command doesn't make
%    any |\global| changes. The coding is very similar to part of
%    |\selectlanguage|.
% \changes{babel~3.5d}{1995/06/22}{Macro added}
% \changes{babel~3.6d}{1997/01/07}{Introduced \cs{foreign@language}}
% \changes{babel~3.7a}{1998/03/12}{Added executing \cs{originalTeX}}
% \changes{babel~3.9a}{2012/07/30}{Removed unnecesary \cs{noextras}
%    just before closing the group}
% \changes{babel~3.9a}{2012/07/31}{Moved \cs{originalTeX} to
%    \cs{foreing@language} so that it's also used in
%    \texttt{otherlanguage*}}
% \changes{babel~3.9a}{2012/12/24}{\cs{foreignlanguage} defined
%    similarly to \cs{selectlanguage}, protecting the whole macro}
%    \begin{macrocode}
\edef\foreignlanguage{%
  \noexpand\protect
  \expandafter\noexpand\csname foreignlanguage \endcsname}
\expandafter\def\csname foreignlanguage \endcsname#1#2{%
  \begingroup
    \foreign@language{#1}%
    #2%
  \endgroup}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\foreign@language}
% \changes{babel~3.6d}{1997/01/07}{New macro} This macro does the
%    work for |\foreignlanguage| and the \Lenv{otherlanguage*}
%    environment. First we need to store the name of the language and
%    check that it is a known language. Then it just calls
%    |bbl@switch|.
% \changes{babel~3.9h}{2013/11/29}{The warning shows the language
%    actually selected (with fixed case)}
%    \begin{macrocode}
\def\foreign@language#1{%
  \edef\languagename{#1}%
  \bbl@fixname\languagename
  \bbl@iflanguage\languagename{%
    \expandafter\ifx\csname date\languagename\endcsname\relax
      \bbl@warning
        {You haven't loaded the language \languagename\space yet\\%
         I'll proceed, but expect unexpected results.\\%
         Reported}%
    \fi
    \let\bbl@select@type\@ne
    \expandafter\bbl@switch\expandafter{\languagename}}}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\bbl@patterns}
% \changes{babel~3.8l}{2008/07/06}{Macro added}
% \changes{babel~3.9a}{2012/08/28}{Extended to set hyphenation
%    exceptions as defined with \cs{babelhyphenation}}
%    This macro selects the hyphenation patterns by changing the
%    \cs{language} register.  If special hyphenation patterns
%    are available specifically for the current font encoding,
%    use them instead of the default.
%
%    It also sets hyphenation exceptions, but only once, because they
%    are global (here language |\lccode|'s has been set,
%    too). |\bbl@hyphenation@| is set to relax until the very first
%    |\babelhyphenation|, so do nothing with this value. If the
%    exceptions for a language (by its number, not its name, so that
%    |:ENC| is taken into account) has been set, then use
%    |\hyphenation| with both global and language exceptions and empty
%    the latter to mark they must not be set again.
%    \begin{macrocode}
\let\bbl@hyphlist\@empty
\let\bbl@hyphenation@\relax
\let\bbl@hymapsel=\@cclv
\def\bbl@patterns#1{%
  \language=\expandafter\ifx\csname l@#1:\f@encoding\endcsname\relax
      \csname l@#1\endcsname
      \edef\bbl@tempa{#1}%
    \else
      \csname l@#1:\f@encoding\endcsname
      \edef\bbl@tempa{#1:\f@encoding}%
    \fi\relax
  \@expandtwoargs\bbl@usehooks{patterns}{{#1}{\bbl@tempa}}%
  \@ifundefined{bbl@hyphenation@}{}{%
    \begingroup
      \@expandtwoargs\in@{,\number\language,}{,\bbl@hyphlist}%
      \ifin@\else
        \@expandtwoargs\bbl@usehooks{hyphenation}{{#1}{\bbl@tempa}}%
        \hyphenation{%
          \bbl@hyphenation@
          \@ifundefined{bbl@hyphenation@#1}%
            \@empty
            {\space\csname bbl@hyphenation@#1\endcsname}}%
        \xdef\bbl@hyphlist{\bbl@hyphlist\number\language,}%
      \fi
    \endgroup}}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{environment}{hyphenrules}
% \changes{babel~3.7e}{2000/01/28}{Added environment hyphenrules}
%    The environment \Lenv{hyphenrules} can be used to select
%    \emph{just} the hyphenation rules. This environment does
%    \emph{not} change |\languagename| and when the hyphenation rules
%    specified were not loaded it has no effect. Note however,
%    |\lccode|'s and font encodings are not set at all, so in most
%    cases you should use |otherlanguage*|.
% \changes{babel~3.8j}{2008/03/16}{Also set the hyphenmin parameters to
%    the correct value (PR3997)} 
% \changes{babel~3.8l}{2008/07/06}{Use \cs{bbl@patterns}}
%    \begin{macrocode}
\def\hyphenrules#1{%
  \edef\languagename{#1}%
  \bbl@fixname\languagename
  \bbl@iflanguage\languagename{%
    \expandafter\bbl@patterns\expandafter{\languagename}%
    \languageshorthands{none}%
    \expandafter\ifx\csname\languagename hyphenmins\endcsname\relax
      \set@hyphenmins\tw@\thr@@\relax
    \else
      \expandafter\expandafter\expandafter\set@hyphenmins
      \csname\languagename hyphenmins\endcsname\relax
    \fi}}
\let\endhyphenrules\@empty
%    \end{macrocode}
%  \end{environment}
%
%  \begin{macro}{\providehyphenmins}
% \changes{babel~3.7f}{2000/02/18}{added macro}
%    The macro |\providehyphenmins| should be used in the language
%    definition files to provide a \emph{default} setting for the
%    hyphenation parameters |\lefthyphenmin| and |\righthyphenmin|. If
%    the macro |\|\langvar|hyphenmins| is already defined this command
%    has no effect.
%    \begin{macrocode}
\def\providehyphenmins#1#2{%
  \expandafter\ifx\csname #1hyphenmins\endcsname\relax
    \@namedef{#1hyphenmins}{#2}%
  \fi}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\set@hyphenmins}
%    This macro sets the values of |\lefthyphenmin| and
%    |\righthyphenmin|. It expects two values as its argument.
%    \begin{macrocode}
\def\set@hyphenmins#1#2{\lefthyphenmin#1\relax\righthyphenmin#2\relax}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\ProvidesLanguage}
% \changes{babel~3.7a}{1997/03/18}{Added macro to prevent problems
%    with unexpected \cs{ProvidesFile} in plain formats because of
%    \babel.}
%    The identification code for each file is something that was
%    introduced in \LaTeXe. When the command |\ProvidesFile| does not
%    exist, a dummy definition is provided temporarily. For use in the
%    language definition file the command |\ProvidesLanguage| is
%    defined by \babel.
%
%    Depending on the format, ie, on if the former is defined, we use
%    a similar definition or not.
%    \changes{babel~3.4e}{1994/06/24}{Redid the identification code,
%    provided dummy definition of \cs{ProvidesFile} for plain \TeX}
%    \changes{babel~3.5f}{1995/07/26}{Store version in
%    \cs{fileversion}} \changes{babel~3.5f}{1995/12/18}{Need to
%    temporarily change the definition of \cs{ProvidesFile} for
%    December 1995 release} \changes{babel~3.5g}{1996/07/09}{Save a
%    few csnames; use \cs{bbl@tempa} instead of \cs{\@ProvidesFile}
%    and store message in \cs{toks8}}
%    \changes{babel~3.9a}{2012/12/09}{Save info about the babel
%    version in the format (switch.def) so that it can be checked
%    later if necessary}
%    \begin{macrocode}
\ifx\ProvidesFile\@undefined
  \def\ProvidesLanguage#1[#2 #3 #4]{%
    \wlog{Language: #1 #4 #3 <#2>}%
    }
\else
  \def\ProvidesLanguage#1{%
    \begingroup
      \catcode`\ 10 %
      \@makeother\/%
      \@ifnextchar[%]
        {\@provideslanguage{#1}}{\@provideslanguage{#1}[]}}
  \def\@provideslanguage#1[#2]{%
    \wlog{Language: #1 #2}%
    \expandafter\xdef\csname ver@#1.ldf\endcsname{#2}%
    \endgroup}
\fi
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\LdfInit}
% \changes{babel~3.6a}{1996/10/16}{Macro added}
%    This macro is defined in two versions. The first version is to be
%    part of the `kernel' of \babel, ie. the part that is loaded in
%    the format; the second version is defined in \file{babel.def}.
%    The version in the format just checks the category code of the
%    ampersand and then loads \file{babel.def}.
%
%    The category code of the ampersand is restored and the macro
%    calls itself again with the new definition from
%    \file{babel.def}
%    \begin{macrocode}
\def\LdfInit{%
  \chardef\atcatcode=\catcode`\@
  \catcode`\@=11\relax
  \input babel.def\relax
  \catcode`\@=\atcatcode \let\atcatcode\relax
  \LdfInit}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\originalTeX}
%    The macro|\originalTeX| should be known to \TeX\ at this moment.
%    As it has to be expandable we |\let| it to |\@empty| instead of
%    |\relax|.
% \changes{babel~3.2a}{1991/11/24}{Set \cs{originalTeX} to
%    \cs{empty}, because it should be expandable.}
%    \begin{macrocode}
\ifx\originalTeX\@undefined\let\originalTeX\@empty\fi
%    \end{macrocode}
%    Because this part of the code can be included in a format, we
%    make sure that the macro which initialises the save mechanism,
%    |\babel@beginsave|, is not considered to be undefined.
%    \begin{macrocode}
\ifx\babel@beginsave\@undefined\let\babel@beginsave\relax\fi
%    \end{macrocode}
%  \end{macro}
%
%    \subsection{Errors}
%
%  \begin{macro}{\@nolanerr}
% \changes{babel~3.4e}{1994/06/25}{Use \cs{PackageError} in \LaTeXe\
%    mode}
%  \begin{macro}{\@nopatterns}
% \changes{babel~3.4e}{1994/06/25}{Macro added}
%    The \babel\ package will signal an error when a documents tries
%    to select a language that hasn't been defined earlier. When a
%    user selects a language for which no hyphenation patterns were
%    loaded into the format he will be given a warning about that
%    fact. We revert to the patterns for |\language|=0 in that case.
%    In most formats that will be (US)english, but it might also be
%    empty.
%  \begin{macro}{\@noopterr}
% \changes{babel~3.7m}{2003/11/16}{Macro added}
%    When the package was loaded without options not everything will
%    work as expected. An error message is issued in that case.
%
%    When the format knows about |\PackageError| it must be \LaTeXe,
%    so we can safely use its error handling interface. Otherwise
%    we'll have to `keep it simple'.
% \changes{babel~3.0d}{1991/10/07}{Added a percent sign to remove
%    unwanted white space}
% \changes{babel~3.5a}{1995/02/15}{Added \cs{@activated} to log active
%    characters}
% \changes{babel~3.5c}{1995/06/19}{Added missing closing brace}
% \changes{babel~3.9a}{2012/07/30}{\cs{newcommand}s replaced by
%    \cs{def}'s, so that the file can be loaded twice}
% \changes{babel~3.9a}{2013/01/26}{Define generic variants instead of
%    duplicating each predefined message}    
%    \begin{macrocode}
\edef\bbl@nulllanguage{\string\language=0}
\ifx\PackageError\@undefined
  \def\bbl@error#1#2{%
    \begingroup
      \newlinechar=`\^^J
      \def\\{^^J(babel) }%
      \errhelp{#2}\errmessage{\\#1}%
    \endgroup}
  \def\bbl@warning#1{%
    \begingroup
      \newlinechar=`\^^J
      \def\\{^^J(babel) }%
      \message{\\#1}%
    \endgroup}
  \def\bbl@info#1{%
    \begingroup
      \newlinechar=`\^^J
      \def\\{^^J}%
      \wlog{#1}%
    \endgroup}
\else
  \def\bbl@error#1#2{%
    \begingroup
      \def\\{\MessageBreak}%
      \PackageError{babel}{#1}{#2}%
    \endgroup}
  \def\bbl@warning#1{%
    \begingroup
      \def\\{\MessageBreak}%
      \PackageWarning{babel}{#1}%
    \endgroup}
  \def\bbl@info#1{%
    \begingroup
      \def\\{\MessageBreak}%
      \PackageInfo{babel}{#1}%
    \endgroup}
\fi
\@ifpackagewith{babel}{silent}
  {\let\bbl@info\@gobble
   \let\bbl@warning\@gobble}
  {}
\def\@nolanerr#1{%
  \bbl@error
    {You haven't defined the language #1\space yet}%
    {Your command will be ignored, type <return> to proceed}}
\def\@nopatterns#1{%
  \bbl@warning
    {No hyphenation patterns were preloaded for\\%
     the language `#1' into the format.\\%
     Please, configure your TeX system to add them and\\%
     rebuild the format. Now I will use the patterns\\%
     preloaded for \bbl@nulllanguage\space instead}}
\let\bbl@usehooks\@gobbletwo
%</kernel>
%    \end{macrocode}
%  \end{macro}
%  \end{macro}
%  \end{macro}
%
%    \section{Loading hyphenation patterns}
%
%  The following code is meant to be read by ini\TeX\ because it
%  should instruct \TeX\ to read hyphenation patterns. To this end the
%  \texttt{docstrip} option \texttt{patterns} can be used to include
%  this code in the file \file{hyphen.cfg}. Code is written with lower
%  level macros.
%
%    |toks8| stores info to be shown when the program is run.
%
% \changes{babel~3.9g}{2013/05/30}{Code moved from plain.def}
% \changes{bbplain-1.0c}{1995/11/08}{Moved the \cs{dump} code here from
%    \file{babel.dtx}}
% \changes{bbplain-0.1}{1991/10/31}{Added redefinition of \cs{dump} to
%    add a message to \cs{everyjob}}
%    We want to add a message to the message \LaTeX$\:$2.09 puts in
%    the |\everyjob| register. This could be done by the following
%    code: 
%    \begin{verbatim}
%    \let\orgeveryjob\everyjob
%    \def\everyjob#1{%
%      \orgeveryjob{#1}%
%      \orgeveryjob\expandafter{\the\orgeveryjob\immediate\write16{%
%          hyphenation patterns for \the\loaded@patterns loaded.}}%
%      \let\everyjob\orgeveryjob\let\orgeveryjob\@undefined}
%    \end{verbatim}
%    The code above redefines the control sequence \cs{everyjob}
%    in order to be able to add something to the current contents of
%    the register. This is necessary because the processing of
%    hyphenation patterns happens long before \LaTeX\ fills the
%    register.
%
%    There are some problems with this approach though.
%  \begin{itemize}
%    \item When someone wants to use several hyphenation patterns with
%    \SliTeX\ the above scheme won't work. The reason is that \SliTeX\
%    overwrites the contents of the |\everyjob| register with its own
%    message.
%    \item Plain \TeX\ does not use the |\everyjob| register so the
%    message would not be displayed.
%  \end{itemize}
%    To circumvent this a `dirty trick' can be used. As this code is
%    only processed when creating a new format file there is one
%    command that is sure to be used, |\dump|. Therefore the original
%    |\dump| is saved in |\org@dump| and a new definition is supplied.
%
%    To make sure that \LaTeX$\:$2.09 executes the
%    |\@begindocumenthook| we would want to alter |\begin{document}|,
%    but as this done too often already, we add the new code at the
%    front of |\@preamblecmds|. But we can only do that after it has
%    been defined, so we add this piece of code to |\dump|.
% \changes{bbplain-1.0c}{1995/11/19}{Add execution of
%    \cs{@begindocumenthook} to \cs{@preamblecmds}} 
% \changes{bbplain-1.0i}{1997/01/02}{\cs{document} is not a
%    \LaTeX2.09-only command; AMS\TeX defines it too; now use
%    \cs{@ztryfc} to detect \LaTeX2.09} 
% \changes{bbplain-1.0j}{1997/01/07}{Add the definition of
%    \cs{@begindocumenthook} to the \LaTeX2.09 format} 
%
%    This new definition starts by adding an instruction to write a
%    message on the terminal and in the transcript file to inform the
%    user of the preloaded hyphenation patterns.
% \changes{bbplain-1.0f}{1996/07/09}{Use \cs{toks8} instead of
%    \cs{patterns@loaded}} 
%
%    Then everything is restored to the old situation and the format
%    is dumped.
%   
%    \begin{macrocode}
%<*patterns>
<@Make sure ProvidesFile is defined@>
\ProvidesFile{hyphen.cfg}[<@date@> <@version@> Babel hyphens]
\xdef\bbl@format{\jobname}
\ifx\AtBeginDocument\@undefined
  \def\@empty{}
  \let\orig@dump\dump
  \def\dump{%
    \ifx\@ztryfc\@undefined
    \else
      \toks0=\expandafter{\@preamblecmds}%
      \edef\@preamblecmds{\noexpand\@begindocumenthook\the\toks0}%
      \def\@begindocumenthook{}%
    \fi
    \let\dump\orig@dump\let\orig@dump\@undefined\dump}
\fi
<@Define core switching macros@>
\toks8{Babel <<@version@>> and hyphenation patterns for }%
%    \end{macrocode}
%
% \changes{babel~3.5g}{1996/07/09}{Removed the use of
%    \cs{patterns@loaded} altogether}
%
%  \begin{macro}{\process@line}
% \changes{babel~3.5b}{1995/04/28}{added macro}
%    Each line in the file \file{language.dat} is processed by
%    |\process@line| after it is read. The first thing this macro does
%    is to check whether the line starts with \texttt{=}.
%    When the first token of a line is an \texttt{=}, the macro
%    |\process@synonym| is called; otherwise the macro
%    |\process@language| will continue.
% \changes{babel~3.5g}{1996/07/09}{Simplified code, removing
%    \cs{bbl@eq@}}
% \changes{babel~3.9a}{2012/12/12}{Use spaces as delimiters, to avoid
%    extra spaces. Once parsed, pass them in the traditional way}
%    \begin{macrocode}   
\def\process@line#1#2 #3 #4 {%
  \ifx=#1%
    \process@synonym{#2}%
  \else
    \process@language{#1#2}{#3}{#4}%
  \fi
  \ignorespaces}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\process@synonym}
% \changes{babel~3.5b}{1995/04/28}{added macro}
% \changes{babel~3.7c}{1999/04/27}{Use a token register to temporarily
%    store a command to set hyphenmin parameters for the synonym which
%    is defined \emph{before} the first pattern file is processed}
%
%    This macro takes care of the lines which start with an
%    \texttt{=}. It needs an empty token register to begin with.
%    |\bbl@languages| is also set to empty. 
%    \begin{macrocode}
\toks@{}
\def\bbl@languages{}
%    \end{macrocode}
%    When no languages have been loaded yet, the name following the
%    \texttt{=} will be a synonym for hyphenation register 0. So, it is stored
%    in a token register and executed when the first pattern file has
%    been processed. (The |\relax| just helps to the |\if| below
%    catching synonyms without a language.)
%
%    Otherwise the name will be a synonym for the language loaded last.
%
%    We also need to copy the hyphenmin parameters for the synonym.
% \changes{babel~3.7c}{1999/04/22}{Now also store hyphenmin parameters
%    for language synonyms}
% \changes{babel~3.9a}{2012/06/25}{Added \cs{bbl@languages}}
%    \begin{macrocode}
\def\process@synonym#1{%
  \ifnum\last@language=\m@ne
    \toks@\expandafter{\the\toks@\relax\process@synonym{#1}}%
  \else
    \expandafter\chardef\csname l@#1\endcsname\last@language
    \wlog{\string\l@#1=\string\language\the\last@language}%
    \expandafter\let\csname #1hyphenmins\expandafter\endcsname
      \csname\languagename hyphenmins\endcsname
    \let\bbl@elt\relax
    \edef\bbl@languages{\bbl@languages\bbl@elt{#1}{\the\last@language}{}{}}%
  \fi}
%    \end{macrocode}
%  \end{macro}
%
%  \begin{macro}{\process@language}
%    The macro |\process@language| is used to process a non-empty line
%    from the `configuration file'. It has three arguments, each
%    delimited by white space. The first argument is the `name' of a
%    language; the second is the name of the file that contains the
%    patterns. The optional third argument is the name of a file
%    containing hyphenation exceptions.
%
%    The first thing to do is call |\addlanguage| to allocate a
%    pattern register and to make that register `active'.
% \changes{babel~3.0d}{1991/08/08}{Removed superfluous
%    \cs{expandafter}}
% \changes{babel~3.0d}{1991/08/21}{Reinserted \cs{expandafter}}
% \changes{babel~3.0d}{1991/10/27}{Added the collection of pattern
%    names.}
% \changes{babel~3.7c}{1999/04/22}{Also store \cs{languagename} for
%    possible later use in \cs{process@synonym}}
%    Then the `name' of the language that will be loaded now is
%    added to the token register |\toks8|. and finally
%    the pattern file is read.
% \changes{babel~3.7f}{2000/02/18}{Allow for the encoding to be used
%    as part of the language name} 
% \changes{babel~3.9a}{2012/12/10}{Removed \cs{selectfont} (I presume
%    it was intended to catch wrong encoding codes, but I don't think
%    this is necessary and as a side effect it might preload fonts)}
%
%    For some hyphenation patterns it is needed to load them with a
%    specific font encoding selected. This can be specified in the
%    file \file{language.dat} by adding for instance `\texttt{:T1}' to
%    the name of the language. The macro |\bbl@get@enc| extracts the
%    font encoding from the language name and stores it in
%    |\bbl@hyph@enc|. The latter can be used in hyphenation files if
%    you need to set a behaviour depending on the given encoding (it
%    is set to empty if no encoding is given).
%
% \changes{babel~3.4e}{1994/06/24}{Added code to detect assignments to
%    left- and righthyphenmin in the patternfile.}
% \changes{babel~3.7a}{1998/03/27}{Read pattern files in a group}
% \changes{babel~3.7c}{1999/04/05}{need to set hyphenmin values
%    globally}
% \changes{babel~3.7c}{1999/04/22}{Set \cs{lefthyphenmin} to \cs{m@ne}
%    \emph{inside} the group; explicitly set the hyphenmin parameters
%    for language 0}
% \changes{babel~3.7c}{1999/04/25}{Only set hyphenmin values when the
%    pattern file changed them}
%    Pattern files may contain assignments to |\lefthyphenmin| and
%    |\righthyphenmin|. \TeX\ does not keep track of these
%    assignments. Therefore we try to detect such assignments and
%    store them in the |\|\langvar|hyphenmins| macro. When no
%    assignments were made we provide a default setting.
%
%    Some pattern files contain changes to the |\lccode| en |\uccode|
%    arrays. Such changes should remain local to the language;
%    therefore we process the pattern file in a group; the |\patterns|
%    command acts globally so its effect will be remembered.
%
%    Then we globally store the settings of |\lefthyphenmin| and
%    |\righthyphenmin| and close the group.
%
%    When the hyphenation patterns have been processed we need to see
%    if a file with hyphenation exceptions needs to be read. This is
%    the case when the third argument is not empty and when it does
%    not contain a space token. (Note however there is no need to save
%    hyphenation exceptions into the format.)
% \changes{babel~3.5b}{1995/04/28}{Added optional reading of file with
%    hyphenation exceptions}
% \changes{babel~3.5f}{1995/07/25}{Use \cs{empty} instead of
%    \cs{@empty} as the latter is unknown in plain}
%
% \changes{babel~3.9a}{2012/06/25}{Added \cs{bbl@languages}}
% \changes{babel~3.9f}{2013/05/16}{Restored code to set default
%    hyphenmins, which was deleted mistakenly} 
%    \cs{bbl@languages} saves a snapshot of the loaded languagues in the
%    form  \cs{bbl@elt}\marg{language-name}\marg{number}%
%    \marg{patterns-file}\marg{exceptions-file}. Note the last 2
%    arguments are empty in `dialects' defined in |language.dat| with
%    |=|. Note also the language name can have encoding info.
%
% \changes{babel~3.7c}{1999/04/27}{Added the execution of the contents
%    of \cs{toks@}}
%    Finally, if the counter |\language| is equal to zero we execute the
%    synonyms stored.
%    \begin{macrocode}
\def\process@language#1#2#3{%
  \expandafter\addlanguage\csname l@#1\endcsname
  \expandafter\language\csname l@#1\endcsname
  \edef\languagename{#1}%
  \bbl@hook@everylanguage{#1}%
  \bbl@get@enc#1::\@@@
  \begingroup
    \lefthyphenmin\m@ne
    \bbl@hook@loadpatterns{#2}%
    \ifnum\lefthyphenmin=\m@ne
    \else
      \expandafter\xdef\csname #1hyphenmins\endcsname{%
        \the\lefthyphenmin\the\righthyphenmin}%
    \fi
  \endgroup
  \def\bbl@tempa{#3}%
  \ifx\bbl@tempa\@empty\else
    \bbl@hook@loadexceptions{#3}%
  \fi
  \let\bbl@elt\relax
  \edef\bbl@languages{%
    \bbl@languages\bbl@elt{#1}{\the\language}{#2}{\bbl@tempa}}%
  \ifnum\the\language=\z@
    \expandafter\ifx\csname #1hyphenmins\endcsname\relax
      \set@hyphenmins\tw@\thr@@\relax
    \else
      \expandafter\expandafter\expandafter\set@hyphenmins
        \csname #1hyphenmins\endcsname
    \fi
    \the\toks@
    \toks@{}%
  \fi}
%    \end{macrocode}
%
%  \begin{macro}{\bbl@get@enc}
% \changes{babel~3.7f}{2000/02/18}{Added macro}
% \changes{babel~3.9a}{2012/12/11}{Code much simplified}
%  \begin{macro}{\bbl@hyph@enc}
%    The macro |\bbl@get@enc| extracts the font encoding from the
%    language name and stores it in |\bbl@hyph@enc|. It uses delimited
%    arguments to achieve this.
%    \begin{macrocode}
\def\bbl@get@enc#1:#2:#3\@@@{\def\bbl@hyph@enc{#2}}
%    \end{macrocode}
%  \end{macro}
%  \end{macro}
%  \end{macro}
%
%    Now, hooks are defined. For efficiency reasons, they are dealt
%    here in a special way. Besides \luatex, format specific
%    configuration files are taken into account.
% \changes{babel~3.9b}{2013/03/25}{Fixed an idiot slip: \cs{def}
%   intead of \cs{let}}
%    \begin{macrocode}
\def\bbl@hook@everylanguage#1{}
\def\bbl@hook@loadpatterns#1{\input #1\relax}
\let\bbl@hook@loadexceptions\bbl@hook@loadpatterns
\let\bbl@hook@loadkernel\bbl@hook@loadpatterns
\begingroup
  \def\AddBabelHook#1#2{%
    \expandafter\ifx\csname bbl@hook@#2\endcsname\relax
      \def\next{\toks1}%
    \else
      \def\next{\expandafter\gdef\csname bbl@hook@#2\endcsname####1}%
    \fi
    \next}
  \ifx\directlua\@undefined
    \ifx\XeTeXinputencoding\@undefined\else
      \input xebabel.def
    \fi
  \else
    \input luababel.def
  \fi
  \openin1 = babel-\bbl@format.cfg
  \ifeof1
  \else
    \input babel-\bbl@format.cfg\relax
  \fi
  \closein1
\endgroup
\bbl@hook@loadkernel{switch.def}
%    \end{macrocode}
%  \begin{macro}{\readconfigfile}
%    The configuration file can now be opened for reading.
%    \begin{macrocode}
\openin1 = language.dat
%    \end{macrocode}
%
%    See if the file exists, if not, use the default hyphenation file
%    \file{hyphen.tex}. The user will be informed about this.
%
%    \begin{macrocode}
\def\languagename{english}%
\ifeof1
  \message{I couldn't find the file language.dat,\space
           I will try the file hyphen.tex}
  \input hyphen.tex\relax
  \chardef\l@english\z@
\else
%    \end{macrocode}
%
%    Pattern registers are allocated using count register
%    |\last@language|. Its initial value is~0. The definition of the
%    macro |\newlanguage| is such that it first increments the count
%    register and then defines the language. In order to have the
%    first patterns loaded in pattern register number~0 we initialize
%    |\last@language| with the value~$-1$.
%
% \changes{babel~3.1}{1991/05/21}{Removed use of \cs{toks0}}
%    \begin{macrocode}
  \last@language\m@ne
%    \end{macrocode}
%
%    We now read lines from the file until the end is found
%
%    \begin{macrocode}
  \loop
%    \end{macrocode}
%
%    While reading from the input, it is useful to switch off
%    recognition of the end-of-line character. This saves us stripping
%    off spaces from the contents of the control sequence.
%
%    \begin{macrocode}
    \endlinechar\m@ne
    \read1 to \bbl@line
    \endlinechar`\^^M
%    \end{macrocode}
%
% \changes{babel~3.9a}{2012/12/14}{Test simplified and moved}
% \changes{babel~3.9a}{2012/12/12}{Use only spaces as delimiters and
%    not /, as previouly done} 
%
%    If the file has reached its end, exit from the loop here. If not,
%    empty lines are skipped. Add 3 space characters to the end of
%    |\bbl@line|. This is needed to be able to recognize the arguments
%    of |\process@line| later on. The default language should be the
%    very first one.
%
%    \begin{macrocode}
    \if T\ifeof1F\fi T\relax
      \ifx\bbl@line\@empty\else
        \edef\bbl@line{\bbl@line\space\space\space}%
        \expandafter\process@line\bbl@line\relax
      \fi
  \repeat
%    \end{macrocode}
%
%    Check for the end of the file. We must reverse the test for
%    |\ifeof| without |\else|. Then reactivate the default patterns,
% \changes{babel~3.8m}{2008/07/08}{Also restore the name of the
%    language in \cs{languagename} (PR 4039)} 
%    \begin{macrocode}
  \begingroup
    \def\bbl@elt#1#2#3#4{%
      \global\language=#2\relax
      \gdef\languagename{#1}%
      \def\bbl@elt##1##2##3##4{}}%
    \bbl@languages
  \endgroup
\fi
%    \end{macrocode}
%    and close the configuration file.
% \changes{babel~3.2a}{1991/11/20}{Free macro space for
%    \cs{process@language}}
%    \begin{macrocode}
\closein1
%    \end{macrocode}
%
% \changes{babel~3.5f}{1995/11/08}{Moved the fiddling with \cs{dump}
%     to \file{bbplain.dtx} as it is no longer needed for \LaTeX}
%    We add a message about the fact that babel is loaded in the
%    format and with which language patterns to the \cs{everyjob}
%    register.
% \changes{babel~3.6h}{1997/01/23}{Added a couple of \cs{expandafter}s
%    to copy the contents of \cs{toks8} into \cs{everyjob} instead of
%    the reference}
% \changes{babel~3.9a}{2012/09/25}{The list of languages is not
%    printed every job any more (it is saved in \cs{bbl@languages}).} 
% \changes{babel~3.9g}{2013/07/28}{In non-LaTeX formats the number of
%    languages were not printed. Moved from \cs{dump} and cleaned up:
%    now \cs{toks}8 is expanded here.} 
%    \begin{macrocode}
\if/\the\toks@/\else
  \errhelp{language.dat loads no language, only synonyms}
  \errmessage{Orphan language synonym}
\fi
\edef\bbl@tempa{%
  \everyjob{%
    \the\everyjob
    \ifx\typeout\@undefined
      \immediate\write16%
    \else
      \noexpand\typeout
    \fi
    {\the\toks8 \the\last@language\space languages loaded.}}}
\bbl@tempa
%    \end{macrocode}
%    Also remove some macros from memory and raise an error
%    if |\toks@| is not empty. Finally load \file{switch.def}, but the
%    letter is not required and the line inputting it may be commented out.
% \changes{babel~3.9a}{2012/12/11}{Raise error if there are synonyms
%    without languages}
%    \begin{macrocode}
\let\bbl@line\@undefined
\let\process@line\@undefined
\let\process@synonym\@undefined
\let\process@language\@undefined
\let\bbl@get@enc\@undefined
\let\bbl@hyph@enc\@undefined
\let\bbl@tempa\@undefined
\let\bbl@hook@loadkernel\@undefined
\let\bbl@hook@everylanguage\@undefined
\let\bbl@hook@loadpatterns\@undefined
\let\bbl@hook@loadexceptions\@undefined
%</patterns>
%    \end{macrocode}
%    Here the code for ini\TeX\ ends.
%  \end{macro}
%
%    \section{The `nil' language}
%
%    This `language' does nothing, except setting the hyphenation patterns to
%    nohyphenation.
%
%    For this language currently no special definitions are needed or
%    available.
%
%    The macro |\LdfInit| takes care of preventing that this file is
%    loaded more than once, checking the category code of the
%    \texttt{@} sign, etc.
%    \begin{macrocode}
%<*nil>
\ProvidesLanguage{nil}[<@date@> <@version@> Nil language]
\LdfInit{nil}{datenil}
%    \end{macrocode}
%
%    When this file is read as an option, i.e. by the |\usepackage|
%    command, \texttt{nil} could be an `unknown' language in which
%    case we have to make it known. 
%    \begin{macrocode}
\ifx\l@nohyphenation\@undefined
   \@nopatterns{nil}
   \adddialect\l@nil0
\else
   \let\l@nil\l@nohyphenation
\fi
%    \end{macrocode}
%    This macro is used to store the values of the hyphenation
%    parameters |\lefthyphenmin| and |\righthyphenmin|.
%    \begin{macrocode}
\providehyphenmins{\CurrentOption}{\m@ne\m@ne}
%    \end{macrocode}
%
%    The next step consists of defining commands to switch to (and
%    from) the `nil' language.
% \begin{macro}{\captionnil}
% \begin{macro}{\datenil}
%    \begin{macrocode}
\let\captionsnil\@empty
\let\datenil\@empty
%    \end{macrocode}
% \end{macro}
% \end{macro}
%  
%    The macro |\ldf@finish| takes care of looking for a
%    configuration file, setting the main language to be switched on
%    at |\begin{document}| and resetting the category code of
%    \texttt{@} to its original value.
%    \begin{macrocode}
\ldf@finish{nil}
%</nil>
%    \end{macrocode}
%
% \changes{bbplain-1.0n}{1998/06/08}{Added the source for the format
%    wrapper files} 
%
%  \section{Support for Plain \TeX}
%
%  \subsection{Not renaming \file{hyphen.tex}}
%    As Don Knuth has declared that the filename \file{hyphen.tex} may
%    only be used to designate \emph{his} version of the american
%    English hyphenation patterns, a new solution has to be found in
%    order to be able to load hyphenation patterns for other languages
%    in a plain-based \TeX-format. 
%    When asked he responded:
%    \begin{quote}
%      That file name is ``sacred'', and if anybody changes it they will
%      cause severe upward/downward compatibility headaches.
%
%      People can have a file localhyphen.tex or whatever they like,
%      but they mustn't diddle with hyphen.tex (or plain.tex except to
%      preload additional fonts). 
%    \end{quote}
%
%    The files \file{bplain.tex} and \file{blplain.tex} can be used as
%    replacement wrappers around \file{plain.tex} and
%    \file{lplain.tex} to acheive the desired effect, based on the
%    \pkg{babel} package. If you load each of them with ini\TeX, you
%    will get a file called either \file{bplain.fmt} or
%    \file{blplain.fmt}, which you can use as replacements for
%    \file{plain.fmt} and \file{lplain.fmt}.
%
%    As these files are going to be read as the first thing ini\TeX\
%    sees, we need to set some category codes just to be able to
%    change the definition of |\input|
%    \begin{macrocode}
%<*bplain|blplain>
\catcode`\{=1 % left brace is begin-group character
\catcode`\}=2 % right brace is end-group character
\catcode`\#=6 % hash mark is macro parameter character
%    \end{macrocode}
%    Now let's see if a file called \file{hyphen.cfg} can be found
%    somewhere on \TeX's input path by trying to open it for
%    reading... 
%    \begin{macrocode}
\openin 0 hyphen.cfg
%    \end{macrocode}
%    If the file wasn't found the following test turns out true.
%    \begin{macrocode}
\ifeof0
\else
%    \end{macrocode}
%    When \file{hyphen.cfg} could be opened we make sure that
%    \emph{it} will be read instead of the file \file{hyphen.tex}
%    which should (according to Don Knuth's ruling) contain the
%    american English hyphenation patterns and nothing else.
%
%    We do this by first saving the original meaning of |\input| (and
%    I use a one letter control sequence for that so as not to waste
%    multi-letter control sequence on this in the format).
%    \begin{macrocode}
  \let\a\input
%    \end{macrocode}
%    Then |\input| is defined to forget about its argument and load
%    \file{hyphen.cfg} instead.
%    \begin{macrocode}
  \def\input #1 {%
    \let\input\a
    \a hyphen.cfg
%    \end{macrocode}
%    Once that's done the original meaning of |\input| can be restored
%    and the definition of |\a| can be forgotten.
%    \begin{macrocode}
    \let\a\undefined
  }
\fi
%</bplain|blplain>
%    \end{macrocode}
%    Now that we have made sure that \file{hyphen.cfg} will be loaded
%    at the right moment it is time to load \file{plain.tex}.
%    \begin{macrocode}
%<bplain>\a plain.tex
%<blplain>\a lplain.tex
%    \end{macrocode}
%    Finally we change the contents of |\fmtname| to indicate that
%    this is \emph{not} the plain format, but a format based on plain
%    with the \pkg{babel} package preloaded.
%    \begin{macrocode}
%<bplain>\def\fmtname{babel-plain}
%<blplain>\def\fmtname{babel-lplain}
%    \end{macrocode}
%
%    When you are using a different format, based on plain.tex you can
%    make a copy of blplain.tex, rename it and replace \file{plain.tex}
%    with the name of your format file.
%
%  \subsection{Emulating some \LaTeX{} features}
%
%    The following code duplicates or emulates parts of \LaTeXe\ that
%    are needed for \babel.
%
% \changes{bbplain-1.0f}{1996/07/09}{Consistently use \cs{@undefined}
%    instead of \cs{undefined}} 
% \changes{bbplain-1.0f}{1996/07/09}{added \cs{@empty}}
% \changes{bbplain-1.0h}{1996/10/07}{Only load the necessary parts
%    into the format, let this file be read agian by babel.def} 
% \changes{bbplain-1.0h}{2012/12/21}{Use \cs{orig@dump} as flag to
%    decide if we are building the format, defined in hyphen.cfg} 
%
%    We need to define |\loadlocalcfg| for plain users as the
%    \LaTeX\ definition uses |\InputIfFileExists|. We have to execute
%    \cs{@endofldf} in this case.
% \changes{bbplain-1.0c}{1995/07/26}{Added definition of
%    \cs{loadlocalcfg}}
% \changes{bbplain-1.0d}{1996/01/08}{Also reset category codes after
%    loading the configuration file as \cs{AtEndOfPackage} is
%    undefined in this case} 
% \changes{bbplain-1.0s}{2012/12/21}{\cs{loadlocalcfg} not loaded in
%    the format} 
%    \begin{macrocode}
%<*plain>
\def\@empty{}
\def\loadlocalcfg#1{%
  \openin0#1.cfg
  \ifeof0
    \closein0
  \else
    \closein0
    {\immediate\write16{*************************************}%
     \immediate\write16{* Local config file #1.cfg used}%
     \immediate\write16{*}%
     }
    \input #1.cfg\relax
  \fi
  \@endofldf}
%    \end{macrocode}
%
% \subsection{General tools}
%
%    A number of \LaTeX\ macro's that are needed later on.
% \changes{bbplain-1.0n}{1998/06/10}{Added \cs{@secondoftwo}}
% \changes{bbplain-1.0q}{1999/09/16}{Added \cs{@ifundefined}}
% \changes{bbplain-1.0t}{2013/04/10}{Added \cs{@expandtwoargs}}
% \changes{babel~3.9h}{2013/12/02}{Added \cs{zap@space}}
% \changes{babel~3.9k}{2014/03/22}{Added \cs{@nnil}}
% \changes{babel~3.9k}{2014/03/22}{Added \cs{@gobbletwo}}
% \changes{babel~3.9k}{2014/03/22}{Added \cs{protected@edef}}
%    \begin{macrocode}
\long\def\@firstofone#1{#1}
\long\def\@firstoftwo#1#2{#1}
\long\def\@secondoftwo#1#2{#2}
\def\@nnil{\@nil}
\def\@gobbletwo#1#2{}
\def\@ifstar#1{\@ifnextchar *{\@firstoftwo{#1}}}
\def\@star@or@long#1{%
  \@ifstar
  {\let\l@ngrel@x\relax#1}%
  {\let\l@ngrel@x\long#1}}
\let\l@ngrel@x\relax
\def\@car#1#2\@nil{#1}
\def\@cdr#1#2\@nil{#2}
\let\@typeset@protect\relax
\let\protected@edef\edef
\long\def\@gobble#1{}
\edef\@backslashchar{\expandafter\@gobble\string\\}
\def\strip@prefix#1>{}
\def\g@addto@macro#1#2{{%
    \toks@\expandafter{#1#2}%
    \xdef#1{\the\toks@}}}
\def\@namedef#1{\expandafter\def\csname #1\endcsname}
\def\@nameuse#1{\csname #1\endcsname}
\def\@ifundefined#1{%
  \expandafter\ifx\csname#1\endcsname\relax
    \expandafter\@firstoftwo
  \else
    \expandafter\@secondoftwo
  \fi}
\def\@expandtwoargs#1#2#3{%
  \edef\reserved@a{\noexpand#1{#2}{#3}}\reserved@a}
\def\zap@space#1 #2{%
  #1%
  \ifx#2\@empty\else\expandafter\zap@space\fi
  #2}
%    \end{macrocode}
%    \LaTeXe\ has the command |\@onlypreamble| which adds commands to
%    a list of commands that are no longer needed after
%    |\begin{document}|.
%    \begin{macrocode}
\ifx\@preamblecmds\@undefined
  \def\@preamblecmds{}
\fi
\def\@onlypreamble#1{%
  \expandafter\gdef\expandafter\@preamblecmds\expandafter{%
    \@preamblecmds\do#1}}
\@onlypreamble\@onlypreamble
%    \end{macrocode}
%    Mimick \LaTeX's |\AtBeginDocument|; for this to work the user
%    needs to add |\begindocument| to his file.
%    \begin{macrocode}
\def\begindocument{%
  \@begindocumenthook
  \global\let\@begindocumenthook\@undefined
  \def\do##1{\global\let##1\@undefined}%
  \@preamblecmds
  \global\let\do\noexpand}
%    \end{macrocode}
%    
% \changes{bbplain-1.0j}{1997/01/07}{\cs{@begindocumenthook} might
%    already be defined} 
% \changes{bbplain-1.0k}{1997/01/14}{missing \cs{@undefined} added}
%    \begin{macrocode}
\ifx\@begindocumenthook\@undefined
  \def\@begindocumenthook{}
\fi
\@onlypreamble\@begindocumenthook
\def\AtBeginDocument{\g@addto@macro\@begindocumenthook}
%    \end{macrocode}
%    We also have to mimick \LaTeX's |\AtEndOfPackage|. Our
%    replacement macro is much simpler; it stores its argument in
%    |\@endofldf|.
%  \changes{babel~3.9h}{2013/11/28}{Set \cs{bbl@hymapopt} to 0 - we
%     presume hyphenmap=off in plain}
%    \begin{macrocode}
\def\AtEndOfPackage#1{\g@addto@macro\@endofldf{#1}}
\@onlypreamble\AtEndOfPackage
\def\@endofldf{}
\@onlypreamble\@endofldf
\let\bbl@afterlang\@empty
\chardef\bbl@hymapopt\z@
%    \end{macrocode}
%    \LaTeX\ needs to be able to switch off writing to its auxiliary
%    files; plain doesn't have them by default.
%  \changes{bbplain-1.0m}{1997/04/28}{Set \cs{if@filesw} to 
%    \cs{iffalse} only for plain \TeX}
% \changes{bbplain-1.0n}{1997/09/11}{Repaired typo and added missing
%    \cs{endcsname}}
%    \begin{macrocode}
\ifx\if@filesw\@undefined
  \expandafter\let\csname if@filesw\expandafter\endcsname
    \csname iffalse\endcsname
\fi
%    \end{macrocode}
%    Mimick \LaTeX's commands to define control sequences.
% \changes{bbplain-1.0e}{1996/02/22}{Provide a more complete emulation
%    of \cs{DeclareRobustCommand} and \cs{newcommand}} 
%    \begin{macrocode}
\def\newcommand{\@star@or@long\new@command}
\def\new@command#1{%
  \@testopt{\@newcommand#1}0}
\def\@newcommand#1[#2]{%
  \@ifnextchar [{\@xargdef#1[#2]}%
                {\@argdef#1[#2]}}
\long\def\@argdef#1[#2]#3{%
  \@yargdef#1\@ne{#2}{#3}}
\long\def\@xargdef#1[#2][#3]#4{%
  \expandafter\def\expandafter#1\expandafter{%
    \expandafter\@protected@testopt\expandafter #1%
    \csname\string#1\expandafter\endcsname{#3}}%
  \expandafter\@yargdef \csname\string#1\endcsname
  \tw@{#2}{#4}}
\long\def\@yargdef#1#2#3{%
  \@tempcnta#3\relax
  \advance \@tempcnta \@ne
  \let\@hash@\relax
  \edef\reserved@a{\ifx#2\tw@ [\@hash@1]\fi}%
  \@tempcntb #2%
  \@whilenum\@tempcntb <\@tempcnta
  \do{%
    \edef\reserved@a{\reserved@a\@hash@\the\@tempcntb}%
    \advance\@tempcntb \@ne}%
  \let\@hash@##%
  \l@ngrel@x\expandafter\def\expandafter#1\reserved@a}
\def\providecommand{\@star@or@long\provide@command}
\def\provide@command#1{%
  \begingroup
    \escapechar\m@ne\xdef\@gtempa{{\string#1}}%
  \endgroup
  \expandafter\@ifundefined\@gtempa
    {\def\reserved@a{\new@command#1}}%
    {\let\reserved@a\relax
     \def\reserved@a{\new@command\reserved@a}}%
   \reserved@a}%
%    \end{macrocode}
%    
%    \begin{macrocode}
\def\DeclareRobustCommand{\@star@or@long\declare@robustcommand}
\def\declare@robustcommand#1{%
   \edef\reserved@a{\string#1}%
   \def\reserved@b{#1}%
   \edef\reserved@b{\expandafter\strip@prefix\meaning\reserved@b}%
   \edef#1{%
      \ifx\reserved@a\reserved@b
         \noexpand\x@protect
         \noexpand#1%
      \fi
      \noexpand\protect
      \expandafter\noexpand\csname
         \expandafter\@gobble\string#1 \endcsname
   }%
   \expandafter\new@command\csname
      \expandafter\@gobble\string#1 \endcsname
}
\def\x@protect#1{%
   \ifx\protect\@typeset@protect\else
      \@x@protect#1%
   \fi
}
\def\@x@protect#1\fi#2#3{%
   \fi\protect#1%
}
%    \end{macrocode}
%
%    The following little macro |\in@| is taken from \file{latex.ltx};
%    it checks whether its first argument is part of its second
%    argument. It uses the boolean |\in@|; allocating a new boolean
%    inside conditionally executed code is not possible, hence the
%    construct with the temporary definition of |\bbl@tempa|.
% \changes{bbplain-1.0o}{1998/07/02}{Added definition of \cs{in@}}
% \changes{bbplain-1.0s}{2013/01/15}{Use \cs{bbl@tempa} as
%    documented}
%    \begin{macrocode}
\def\bbl@tempa{\csname newif\endcsname\ifin@}
\ifx\in@\@undefined
  \def\in@#1#2{%
    \def\in@@##1#1##2##3\in@@{%
      \ifx\in@##2\in@false\else\in@true\fi}%
    \in@@#2#1\in@\in@@}
\else
  \let\bbl@tempa\@empty
\fi
\bbl@tempa
%    \end{macrocode}
%
%    \LaTeX\ has a macro to check whether a certain package was loaded
%    with specific options. The command has two extra arguments which
%    are code to be executed in either the true or false case.
%    This is used to detect whether the document needs one of the
%    accents to be activated (\Lopt{activegrave} and
%    \Lopt{activeacute}). For plain \TeX\ we assume that the user
%    wants them to be active by default. Therefore the only thing we
%    do is execute the third argument (the code for the true case).
% 
%    \begin{macrocode}
\def\@ifpackagewith#1#2#3#4{#3}
%    \end{macrocode}
%    The \LaTeX\ macro |\@ifl@aded| checks whether a file was
%    loaded. This functionality is not needed for plain \TeX\ but we
%    need the macro to be defined as a no-op.
% \changes{bbplain-1.0p}{1999/04/27}{Added \cs{@ifl@aded} as a no-op}
%    \begin{macrocode}
\def\@ifl@aded#1#2#3#4{}
%    \end{macrocode}
%
% \changes{bbplain-1.0e}{1996/01/15}{Added the \cs{newcommand} code}
%    For the following code we need to make sure that the commands
%    |\newcommand| and |\providecommand| exist with some sensible
%    definition. They are not fully equivalent to their \LaTeXe\
%    versions; just enough to make things work in plain~\TeX
%    environments.
%
% \changes{bbplain-1.0k}{1997/01/14}{\cs{newcount} is an \cs{outer}
%    command, can't use it inside an \cs{if} construct} 
% \changes{bbplain-1.0l}{1997/01/19}{Mixed up the definition of 
%    \cs{@tempcntb}}
%    \begin{macrocode}
\ifx\@tempcnta\@undefined
  \csname newcount\endcsname\@tempcnta\relax
\fi
\ifx\@tempcntb\@undefined
  \csname newcount\endcsname\@tempcntb\relax
\fi
%    \end{macrocode}
%    To prevent wasting two counters in \LaTeX$\:$2.09 (because
%    counters with the same name are allocated later by it) we reset
%    the counter that holds the next free counter (|\count10|).
%    \begin{macrocode}
\ifx\bye\@undefined
  \advance\count10 by -2\relax
\fi
\ifx\@ifnextchar\@undefined
  \def\@ifnextchar#1#2#3{%
    \let\reserved@d=#1%
    \def\reserved@a{#2}\def\reserved@b{#3}%
    \futurelet\@let@token\@ifnch}
  \def\@ifnch{%
    \ifx\@let@token\@sptoken
      \let\reserved@c\@xifnch
    \else
      \ifx\@let@token\reserved@d
        \let\reserved@c\reserved@a
      \else
        \let\reserved@c\reserved@b
      \fi
    \fi
    \reserved@c}
  \def\:{\let\@sptoken= } \:  % this makes \@sptoken a space token
  \def\:{\@xifnch} \expandafter\def\: {\futurelet\@let@token\@ifnch}
\fi
\def\@testopt#1#2{%
  \@ifnextchar[{#1}{#1[#2]}}
\def\@protected@testopt#1{%%
  \ifx\protect\@typeset@protect
    \expandafter\@testopt
  \else
    \@x@protect#1%
  \fi}
\long\def\@whilenum#1\do #2{\ifnum #1\relax #2\relax\@iwhilenum{#1\relax
     #2\relax}\fi}
\long\def\@iwhilenum#1{\ifnum #1\expandafter\@iwhilenum
         \else\expandafter\@gobble\fi{#1}}
%    \end{macrocode}
%
%  \subsection{Encoding related macros}
%
%    Code from \file{ltoutenc.dtx}, adapted for use in the plain \TeX\
%    environment. 
%    \begin{macrocode}
\def\DeclareTextCommand{%
   \@dec@text@cmd\providecommand
}
\def\ProvideTextCommand{%
   \@dec@text@cmd\providecommand
}
\def\DeclareTextSymbol#1#2#3{%
   \@dec@text@cmd\chardef#1{#2}#3\relax
}
\def\@dec@text@cmd#1#2#3{%
   \expandafter\def\expandafter#2%
      \expandafter{%
         \csname#3-cmd\expandafter\endcsname
         \expandafter#2%
         \csname#3\string#2\endcsname
      }%
%   \let\@ifdefinable\@rc@ifdefinable
   \expandafter#1\csname#3\string#2\endcsname
}
\def\@current@cmd#1{%
  \ifx\protect\@typeset@protect\else
      \noexpand#1\expandafter\@gobble
  \fi
}
\def\@changed@cmd#1#2{%
   \ifx\protect\@typeset@protect
      \expandafter\ifx\csname\cf@encoding\string#1\endcsname\relax
         \expandafter\ifx\csname ?\string#1\endcsname\relax
            \expandafter\def\csname ?\string#1\endcsname{%
               \@changed@x@err{#1}%
            }%
         \fi
         \global\expandafter\let
           \csname\cf@encoding \string#1\expandafter\endcsname
           \csname ?\string#1\endcsname
      \fi
      \csname\cf@encoding\string#1%
        \expandafter\endcsname
   \else
      \noexpand#1%
   \fi
}
\def\@changed@x@err#1{%
    \errhelp{Your command will be ignored, type <return> to proceed}%
    \errmessage{Command \protect#1 undefined in encoding \cf@encoding}}
\def\DeclareTextCommandDefault#1{%
   \DeclareTextCommand#1?%
}
\def\ProvideTextCommandDefault#1{%
   \ProvideTextCommand#1?%
}
\expandafter\let\csname OT1-cmd\endcsname\@current@cmd
\expandafter\let\csname?-cmd\endcsname\@changed@cmd
\def\DeclareTextAccent#1#2#3{%
  \DeclareTextCommand#1{#2}[1]{\accent#3 ##1}
}
\def\DeclareTextCompositeCommand#1#2#3#4{%
   \expandafter\let\expandafter\reserved@a\csname#2\string#1\endcsname
   \edef\reserved@b{\string##1}%
   \edef\reserved@c{%
     \expandafter\@strip@args\meaning\reserved@a:-\@strip@args}%
   \ifx\reserved@b\reserved@c
      \expandafter\expandafter\expandafter\ifx
         \expandafter\@car\reserved@a\relax\relax\@nil
         \@text@composite
      \else
         \edef\reserved@b##1{%
            \def\expandafter\noexpand
               \csname#2\string#1\endcsname####1{%
               \noexpand\@text@composite
                  \expandafter\noexpand\csname#2\string#1\endcsname
                  ####1\noexpand\@empty\noexpand\@text@composite
                  {##1}%
            }%
         }%
         \expandafter\reserved@b\expandafter{\reserved@a{##1}}%
      \fi
      \expandafter\def\csname\expandafter\string\csname
         #2\endcsname\string#1-\string#3\endcsname{#4}
   \else
     \errhelp{Your command will be ignored, type <return> to proceed}%
     \errmessage{\string\DeclareTextCompositeCommand\space used on
         inappropriate command \protect#1}
   \fi
}
\def\@text@composite#1#2#3\@text@composite{%
   \expandafter\@text@composite@x
      \csname\string#1-\string#2\endcsname
}
\def\@text@composite@x#1#2{%
   \ifx#1\relax
      #2%
   \else
      #1%
   \fi
}
%
\def\@strip@args#1:#2-#3\@strip@args{#2}
\def\DeclareTextComposite#1#2#3#4{%
   \def\reserved@a{\DeclareTextCompositeCommand#1{#2}{#3}}%
   \bgroup
      \lccode`\@=#4%
      \lowercase{%
   \egroup
      \reserved@a @%
   }%
}
%
\def\UseTextSymbol#1#2{%
%   \let\@curr@enc\cf@encoding
%   \@use@text@encoding{#1}%
   #2%
%   \@use@text@encoding\@curr@enc
}
\def\UseTextAccent#1#2#3{%
%   \let\@curr@enc\cf@encoding
%   \@use@text@encoding{#1}%
%   #2{\@use@text@encoding\@curr@enc\selectfont#3}%
%   \@use@text@encoding\@curr@enc
}
\def\@use@text@encoding#1{%
%   \edef\f@encoding{#1}%
%   \xdef\font@name{%
%      \csname\curr@fontshape/\f@size\endcsname
%   }%
%   \pickup@font
%   \font@name
%   \@@enc@update
}
\def\DeclareTextSymbolDefault#1#2{%
   \DeclareTextCommandDefault#1{\UseTextSymbol{#2}#1}%
}
\def\DeclareTextAccentDefault#1#2{%
   \DeclareTextCommandDefault#1{\UseTextAccent{#2}#1}%
}
\def\cf@encoding{OT1}
%    \end{macrocode}
%    Currently we only use the \LaTeXe\ method for accents for those
%    that are known to be made active in \emph{some} language
%    definition file.
%    \begin{macrocode}
\DeclareTextAccent{\"}{OT1}{127}
\DeclareTextAccent{\'}{OT1}{19}
\DeclareTextAccent{\^}{OT1}{94}
\DeclareTextAccent{\`}{OT1}{18}
\DeclareTextAccent{\~}{OT1}{126}
%    \end{macrocode}
%    The following control sequences are used in \file{babel.def}
%    but are not defined for \textsc{plain} \TeX.
% \changes{bbplain-1.0f}{1996/07/10}{Added \cs{textquotedblright} and
%    \cs{textquoteright}} 
% \changes{bbplain-1.0g}{1996/08/15}{Added \cs{ss} and \cs{i}}
% \changes{bbplain-1.0r}{2000/10/02}{Added \cs{textquotedblleft} and
%    \cs{textquoteleft}} 
%    \begin{macrocode}
\DeclareTextSymbol{\textquotedblleft}{OT1}{92}
\DeclareTextSymbol{\textquotedblright}{OT1}{`\"}
\DeclareTextSymbol{\textquoteleft}{OT1}{`\`}
\DeclareTextSymbol{\textquoteright}{OT1}{`\'}
\DeclareTextSymbol{\i}{OT1}{16}
\DeclareTextSymbol{\ss}{OT1}{25}
%    \end{macrocode}
%    For a couple of languages we need the \LaTeX-control sequence
%    |\scriptsize| to be available. Because plain \TeX\ doesn't have
%    such a sofisticated font mechanism as \LaTeX\ has, we just |\let|
%    it to |\sevenrm|.
% \changes{bbplain-1.0f}{1996/07/10}{Added definition of
%    \cs{scriptsize}} 
%    \begin{macrocode}
\ifx\scriptsize\@undefined
  \let\scriptsize\sevenrm
\fi
%    \end{macrocode}
%
%  \subsection{Babel options}
% 
% \changes{babel~3.9k}{2014/03/22}{Moved code from babel.def, and add
%    some new tools (not yet documented)} 
%
% The file |babel.def| expects some definitions made in the \LaTeX{}
% style file. So we must provide them at least some predefined values as
% well some tools to set them (even if not all options are
% available). There in no package options, and therefore and alternative
% mechanism is provided. For the moment, only |\babeloptionstrings| and
% |\babeloptionmath| are provided, which can be defined before loading
% \babel. |\BabelModifiers| can be set too (but not sure it works).
%
% \begin{macrocode}
\let\bbl@opt@shorthands\@nnil
\def\bbl@ifshorthand#1#2#3{#2}%
\ifx\babeloptionstrings\@undefined
  \let\bbl@opt@strings\@nnil
\else
  \let\bbl@opt@strings\babeloptionstrings
\fi
\def\bbl@tempa{normal}
\ifx\babeloptionmath\bbl@tempa
  \def\bbl@mathnormal{\noexpand\textormath}
\fi
\def\BabelStringsDefault{generic}
\ifx\BabelModifiers\@undefined\let\BabelModifiers\relax\fi
\let\bbl@afterlang\relax
\let\bbl@language@opts\@empty
\ifx\@uclclist\@undefined\let\@uclclist\@empty\fi
\def\AfterBabelLanguage#1#2{}
%</plain>
%    \end{macrocode}
%
% \Finale
%
%%
%% \CharacterTable
%%  {Upper-case    \A\B\C\D\E\F\G\H\I\J\K\L\M\N\O\P\Q\R\S\T\U\V\W\X\Y\Z
%%   Lower-case    \a\b\c\d\e\f\g\h\i\j\k\l\m\n\o\p\q\r\s\t\u\v\w\x\y\z
%%   Digits        \0\1\2\3\4\5\6\7\8\9
%%   Exclamation   \!     Double quote  \"     Hash (number) \#
%%   Dollar        \$     Percent       \%     Ampersand     \&
%%   Acute accent  \'     Left paren    \(     Right paren   \)
%%   Asterisk      \*     Plus          \+     Comma         \,
%%   Minus         \-     Point         \.     Solidus       \/
%%   Colon         \:     Semicolon     \;     Less than     \<
%%   Equals        \=     Greater than  \>     Question mark \?
%%   Commercial at \@     Left bracket  \[     Backslash     \\
%%   Right bracket \]     Circumflex    \^     Underscore    \_
%%   Grave accent  \`     Left brace    \{     Vertical bar  \|
%%   Right brace   \}     Tilde         \~}
\endinput
%
% Local Variables: 
% mode: doctex
% End: