summaryrefslogtreecommitdiff
path: root/Master/texmf-dist/source/latex/expl3/l3msg.dtx
blob: d3b33f44c552b04fd51063fdb832ba4d38c6636c (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
% \iffalse
%% File: l3msg.dtx Copyright (C) 2009 LaTeX3 project
%%
%% It may be distributed and/or modified under the conditions of the
%% LaTeX Project Public License (LPPL), either version 1.3c of this
%% license or (at your option) any later version.  The latest version
%% of this license is in the file
%%
%%    http://www.latex-project.org/lppl.txt
%%
%% This file is part of the ``expl3 bundle'' (The Work in LPPL)
%% and all files in that bundle must be distributed together.
%%
%% The released version of this bundle is available from CTAN.
%%
%% -----------------------------------------------------------------------
%%
%% The development version of the bundle can be found at
%%
%%    http://www.latex-project.org/svnroot/experimental/trunk/
%%
%% for those people who are interested.
%%
%%%%%%%%%%%
%% NOTE: %%
%%%%%%%%%%%
%%
%%   Snapshots taken from the repository represent work in progress and may
%%   not work or may contain conflicting material!  We therefore ask
%%   people _not_ to put them into distributions, archives, etc. without
%%   prior consultation with the LaTeX Project Team.
%%
%% -----------------------------------------------------------------------
%% 
%
%<*driver|package>
\RequirePackage{l3names}
%</driver|package>
%\fi
\GetIdInfo$Id: l3msg.dtx 1722 2009-11-06 13:22:12Z joseph $
  {L3 Experimental LaTeX Messages module}
%\iffalse
%<*driver>
%\fi
\ProvidesFile{\filename.\filenameext}
  [\filedate\space v\fileversion\space\filedescription]
%\iffalse
\documentclass[full]{l3doc}
\begin{document}
\DocInput{l3msg.dtx}
\end{document}
%</driver>
% \fi
%
% \title{The \textsf{l3msg} package\thanks{This file
%         has version number \fileversion, last
%         revised \filedate.}\\
% Communicating with the user}
% \author{\Team}
% \date{\filedate}
% \maketitle
%
% \begin{documentation}
% 
% Messages need to be passed to the user by modules, either when errors
% occur or to indicate how the code is proceeding. The \pkg{l3msg} 
% module provides a consistent method for doing this (as opposed to
% writing directly to the terminal or log).
% 
% The system used by \pkg{l3msg} to create messages divides the process
% into two distinct parts. Named messages are created in the first part
% of the process; at this stage, no decision is made about the type 
% output that the message will produce. The second part of the process
% is actually producing a message. At this stage a choice of message
% \emph{class} has to be made, for example \texttt{error}, 
% \texttt{warning} or \texttt{info}.
% 
% By separating out the creation and use of messages, several benefits
% are available. First, the messages can be altered later without 
% needing details of where they are used in the code. This makes it
% possible to alter the language used, the detail level and so on. 
% Secondly, the output which results from a given message can be 
% altered. This can be done on a message class, module or message name
% basis. In this way, message behaviour can be altered and messages can
% be entirely suppressed.
% 
% \section{Creating new messages}
% 
% All messages have to be created before they can be used. Inside the 
% message text, spaces are \emph{not} ignored. A space where \TeX\ 
% would normally gobble one can be created using |\ |, and a new line
% with |\\|. New lines may have ``continuation'' text added by the 
% output system.
% 
%\begin{function}{
%  \msg_new:nnnn|
%  \msg_new:nnn|
%  \msg_set:nnnn|
%  \msg_set:nnn
%}
%  \begin{syntax}
%    "\msg_new:nnnn" \marg{module} \marg{name} \marg{text} \marg{more text} 
%  \end{syntax}
%  Creates new message <name> for <module> to produce <text> initially
%  and <more text> if requested by the user. <text> and <more text> can 
%  use up to four macro parameters (|#1| to |#4|), which are supplied by
%  the message system. Inside <text> and <more text> spaces are not 
%  ignored.
%\end{function}
%
% \section{Message classes}
% 
% Creating message output requires the message to be given a class.
%
%\begin{function}{
%  \msg_class_new:nn|
%  \msg_class_set:nn
%}
%  \begin{syntax}
%    "\msg_class_new:nn" \marg{class} \marg{code}
%  \end{syntax}
%  Creates new <class> to output a message, using <code> to process
%  the message text.
%\end{function}
%
% The module defines several common message classes. The following 
% describes the standard behaviour of each class if no redirection of 
% the class or message is active.
%
%\begin{function}{
%  \msg_fatal:nnxxxx|
%  \msg_fatal:nnxxx|
%  \msg_fatal:nnxx|
%  \msg_fatal:nnx|
%  \msg_fatal:nn
%}
%  \begin{syntax}
%    "\msg_fatal:nnxxxx" \marg{module} \marg{name} \marg{arg one}
%     ~~~~\marg{arg two} \marg{arg three} \marg{arg four}
%  \end{syntax}
%  Issues <module> error message <name>, passing <arg one> to 
%  <arg four> to the text-creating functions. The \TeX\ run then halts.
%\end{function}
%
%\begin{function}{
%  \msg_error:nnxxxx|
%  \msg_error:nnxxx|
%  \msg_error:nnxx|
%  \msg_error:nnx|
%  \msg_error:nn
%}
%  \begin{syntax}
%    "\msg_error:nnxxxx" \marg{module} \marg{name} \marg{arg one}
%     ~~~~\marg{arg two} \marg{arg three} \marg{arg four}
%  \end{syntax}
%  Issues <module> error message <name>, passing <arg one> to 
%  <arg four> to the text-creating functions. 
%  \begin{texnote}
%    The standard output here is similar to \cs{PackageError}.
%  \end{texnote}
%\end{function}
%
%\begin{function}{
%  \msg_warning:nnxxxx|
%  \msg_warning:nnxxx|
%  \msg_warning:nnxx|
%  \msg_warning:nnx|
%  \msg_warning:nn
%}
%  \begin{syntax}
%    "\msg_warning:nnxxxx" \marg{module} \marg{name} \marg{arg one}
%     ~~~~\marg{arg two} \marg{arg three} \marg{arg four}
%  \end{syntax}
%  Prints <module> message <name> to the terminal, passing <arg one> to
%  <arg four> to the text-creating functions. 
%  \begin{texnote}
%    The standard output here is similar to \cs{PackageWarningNoLine}.
%  \end{texnote}
%\end{function}
%
%\begin{function}{
%  \msg_info:nnxxxx|
%  \msg_info:nnxxx|
%  \msg_info:nnxx|
%  \msg_info:nnx|
%  \msg_info:nn
%}
%  \begin{syntax}
%    "\msg_info:nnxxxx" \marg{module} \marg{name} \marg{arg one}
%     ~~~~\marg{arg two} \marg{arg three} \marg{arg four}
%  \end{syntax}
%  Prints <module> message <name> to the log, passing <arg one> to
%  <arg four> to the text-creating functions. 
%  \begin{texnote}
%    The standard output here is similar to \cs{PackageInfoNoLine}.
%  \end{texnote}
%\end{function}
%
%\begin{function}{
%  \msg_log:nnxxxx|
%  \msg_log:nnxxx|
%  \msg_log:nnxx|
%  \msg_log:nnx|
%  \msg_log:nn
%}
%  \begin{syntax}
%    "\msg_log:nnxxxx" \marg{module} \marg{name} \marg{arg one}
%     ~~~~\marg{arg two} \marg{arg three} \marg{arg four}
%  \end{syntax}
%  Prints <module> message <name> to the log, passing <arg one> to
%  <arg four> to the text-creating functions. No continuation text is
%  added.
%\end{function}
%
%\begin{function}{
%  \msg_trace:nnxxxx|
%  \msg_trace:nnxxx|
%  \msg_trace:nnxx|
%  \msg_trace:nnx|
%  \msg_trace:nn
%}
%  \begin{syntax}
%    "\msg_trace:nnxxxx" \marg{module} \marg{name} \marg{arg one}
%     ~~~~\marg{arg two} \marg{arg three} \marg{arg four}
%  \end{syntax}
%  Prints <module> message <name> to the log, passing <arg one> to
%  <arg four> to the text-creating functions. No continuation text is
%  added.
%\end{function}
%
%\begin{function}{
%  \msg_none:nnxxxx|
%  \msg_none:nnxxx|
%  \msg_none:nnxx|
%  \msg_none:nnx|
%  \msg_none:nn
%}
%  \begin{syntax}
%    "\msg_none:nnxxxx" \marg{module} \marg{name} \marg{arg one}
%      ~~~~\marg{arg two} \marg{arg three} \marg{arg four}
%  \end{syntax}
%  Does nothing: used for redirecting other message classes. Gobbles 
%  arguments given. 
%\end{function}
% 
% \section{Redirecting messages}
%
%\begin{function}{\msg_redirect_class:nn}
%  \begin{syntax}
%    "\msg_redirect_class:nn" \marg{class one} \marg{class two}
%  \end{syntax}
%  Redirect all messages of <class one> to appear as those of 
%  <class two>.
%\end{function}
%
%\begin{function}{\msg_redirect_module:nnn}
%  \begin{syntax}
%    "\msg_redirect_module:nnn" \marg{module} \marg{class one}
%      \marg{class two}
%  \end{syntax}
%  Redirect <module> messages of <class one> to appear in <class two>.
%  \begin{texnote}
%    This function can be used to make some messages ``silent'' by
%    default. For example, all of the \texttt{trace} messages of
%    <module> could be turned off with: 
%    \begin{verbatim}
%    \msg_redirect_module:nnn { module } { trace } { none }
%    \end{verbatim}
%  \end{texnote}
%\end{function}
%
%\begin{function}{\msg_redirect_name:nnn}
%  \begin{syntax}
%    "\msg_redirect_name:nnn" \marg{module} \marg{message} \marg{class}
%  \end{syntax}
%  Redirect <module> <message> to appear using <class>.
%\end{function}
%
% \section{Support functions for output}
% 
%\begin{function}{\msg_line_context:}
%  \begin{syntax}
%    "\msg_line_context:" 
%  \end{syntax}
%  Prints the current line number preceded by \cs{c_msg_on_line_tl}.
%\end{function}
% 
%\begin{function}{\msg_line_number:}
%  \begin{syntax}
%    "\msg_line_number:" 
%  \end{syntax}
%  Prints the current line number.
%\end{function}
% 
%\begin{function}{
%  \msg_newline:|
%  \msg_two_newlines:
%}
%  \begin{syntax}
%    "\msg_newline:" 
%  \end{syntax}
%  Print one or two newlines with no continuation information.  
%\end{function}
%
%\begin{function}{
%  \msg_space:|
%  \msg_two_spaces:|
%  \msg_four_spaces:
%}
%  \begin{syntax}
%    "\msg_space:" 
%  \end{syntax}
%  Print one, two or four spaces: needed where a literal space would
%  otherwise be gobbled by \TeX.  
%\end{function}
%
% \section{Low-level functions}
% 
% The low-level functions do not make assumptions about module names.
% The output functions here produce messages directly, and do not 
% respond to redirection.
% 
%\begin{function}{
%  \msg_generic_new:nnn|
%  \msg_generic_new:nn|
%  \msg_generic_set:nnn|
%  \msg_generic_set:nn
%}
%  \begin{syntax}
%    "\msg_generic_new:nnn"  \marg{name} \marg{text} \marg{more text} 
%  \end{syntax}
%  Creates new message <name> to produce <text> initially and 
%  <more text> if requested by the user. <text> and <more text>  can use
%  up to four macro parameters (|#1| to |#4|), which are supplied by the
%  message system. Inside <text> and <more text> spaces are not ignored.
%\end{function}
%
%\begin{function}{\msg_direct_interrupt:xxxx}
%  \begin{syntax}
%    "\msg_direct_interrupt:xxxxn"  \marg{first line} \marg{text} 
%    ~~~~\marg{continuation} \marg{more text}
%  \end{syntax}
%  Executes a \TeX\ error, interrupting compilation. The <first line> 
%  is displayed followed by <text> and the input prompt. <more text> is
%  displays if requested by the user. If <more text> is blank a default
%  is supplied. Each line of <text> (broken with |\\|) begins with 
%  <continuation>.
%\end{function}
%
%\begin{function}{
%  \msg_direct_log:xx|
%  \msg_direct_term:xx
%}
%  \begin{syntax}
%    "\msg_direct_log:xx"  \marg{text} \marg{continuation}
%  \end{syntax}
%  Prints <text> to either the log or terminal. New lines (broken 
%  with |\\|) start with <continuation>. 
%\end{function}
%
% \section{Kernel-specific functions}
% 
%\begin{function}{
%  \msg_kernel_new:nnnn|
%  \msg_kernel_new:nnn|
%  \msg_kernel_set:nnnn|
%  \msg_kernel_set:nnn
%}
%  \begin{syntax}
%    "\msg_kernel_new:nnnn" \marg{divsion} \marg{name} \marg{text} 
%     ~~~~\marg{more text}
%  \end{syntax}
%  Creates new kernel message <name> to produce <text> initially and 
%  <more text> if requested by the user. <text> and <more text> can use
%  up to four macro parameters (|#1| to |#4|), which are supplied by the 
%  message system. Kernel messages are divided into <divisions>, roughly
%  equivalent to the \LaTeXe\ package names used.
%\end{function}
%
%\begin{function}{
%  \msg_kernel_fatal:nnxxxx|
%  \msg_kernel_fatal:nnxxx|
%  \msg_kernel_fatal:nnxx|
%  \msg_kernel_fatal:nnx|
%  \msg_kernel_fatal:nn
%}
%  \begin{syntax}
%    "\msg_kernel_fatal:nnxx" \marg{division} \marg{name} \marg{arg one} 
%     ~~~~\marg{arg two} \marg{arg three} \marg{arg four}
%  \end{syntax}
%  Issues kernel error message <name> for <division>, passing <arg one>
%  to <arg four> to the text-creating functions. The \TeX\ run then 
%  halts.  Cannot be redirected.
%\end{function}
%
%\begin{function}{
%  \msg_kernel_error:nnxxxx|
%  \msg_kernel_error:nnxxx|
%  \msg_kernel_error:nnxx|
%  \msg_kernel_error:nnx|
%  \msg_kernel_error:nn
%}
%  \begin{syntax}
%    "\msg_kernel_error:nnxx" \marg{division} \marg{name} \marg{arg one} 
%     ~~~~\marg{arg two} \marg{arg three} \marg{arg four}
%  \end{syntax}
%  Issues kernel error message <name> for <division>, passing <arg one> 
%  to <arg four> to the text-creating functions. Cannot be redirected.
%\end{function}
%
%\begin{function}{
%  \msg_kernel_warning:nnxxxx|
%  \msg_kernel_warning:nnxxx|
%  \msg_kernel_warning:nnxx|
%  \msg_kernel_warning:nnx|
%  \msg_kernel_warning:nn
%}
%  \begin{syntax}
%    "\msg_kernel_warning:nnxx" \marg{division} \marg{name} \marg{arg one} 
%     ~~~~\marg{arg two} \marg{arg three} \marg{arg four}
%  \end{syntax}
%  Prints kernel message <name> for <division> to the terminal, passing 
%  <arg one> to <arg four> to the text-creating functions. 
%\end{function}
%
%\begin{function}{
%  \msg_kernel_info:nnxxxx|
%  \msg_kernel_info:nnxxx|
%  \msg_kernel_info:nnxx|
%  \msg_kernel_info:nnx|
%  \msg_kernel_info:nn
%}
%  \begin{syntax}
%    "\msg_kernel_info:nxx" \marg{division} \marg{name} \marg{arg one} 
%     ~~~~\marg{arg two} \marg{arg three} \marg{arg four}
%  \end{syntax}
%  Prints kernel message <name> for <division> to the log, passing 
%  <arg one> to <arg four> to the text-creating functions. 
%\end{function}
%
%\begin{function}{\msg_kernel_bug:x}
%  \begin{syntax}
%    "\msg_kernel_bug:x" \marg{text}
%  \end{syntax}
%  Short-cut for ``This is a LaTeX bug: check coding'' errors.
%\end{function}
% 
% \section{Variables and constants}
% 
%\begin{variable}{
%  \c_msg_fatal_tl|
%  \c_msg_error_tl|
%  \c_msg_warning_tl|
%  \c_msg_info_tl
%}
%  Simple headers for errors.
%\end{variable}
% 
%\begin{variable}{
%  \c_msg_fatal_text_tl|
%  \c_msg_help_text_tl|
%  \c_msg_kernel_bug_text_tl|
%  \c_msg_kernel_bug_more_text_tl|
%  \c_msg_no_info_text_tl|
%  \c_msg_return_text_tl
%}
%  Various pieces of text for use in messages, which are not changed by
%  the code here although they could be to alter the language.
%\end{variable}
%
%\begin{variable}{\c_msg_on_line_tl}
%  The ``on line'' phrase for line numbers.
%\end{variable}
%
%\begin{variable}{
%  \c_msg_text_prefix_tl|
%  \c_msg_more_text_prefix_tl|
%}
%  Header information for storing the ``paths'' to parts of a message.
%\end{variable}
%
%\begin{variable}{
%  \l_msg_class_tl|
%  \l_msg_current_class_tl
%}
%  Information about message method, used for filtering.
%\end{variable}
%
%\begin{variable}{\l_msg_names_clist}
%  List of all of the message names defined.
%\end{variable}
%
%\begin{variable}{
%  \l_msg_redirect_classes_prop|
%  \l_msg_redirect_names_prop
%}
%  Re-direction lists containing the class of message to convert an 
%  different one.
%\end{variable}
%
%\begin{variable}{\l_msg_redirect_classes_clist}
%  List so that filtering does not loop.
%\end{variable}
% 
% \end{documentation}
% 
% \begin{implementation}
%
% \section{\pkg{l3msg} implementation}
%
% The usual lead-off.
%    \begin{macrocode}
%<*package>
\ProvidesExplPackage
  {\filename}{\filedate}{\fileversion}{\filedescription}
\package_check_loaded_expl:
%</package>
%<*initex|package>
%    \end{macrocode}
%    
% \LaTeX\ is handling context, so the \TeX\ ``noise'' is turned down.
%    \begin{macrocode}
\int_set:Nn \tex_errorcontextlines:D { \c_minus_one }
%    \end{macrocode}
%    
% \subsection{Variables and constants}
%    
%\begin{macro}{\c_msg_fatal_tl}
%\begin{macro}{\c_msg_error_tl}
%\begin{macro}{\c_msg_warning_tl}
%\begin{macro}{\c_msg_info_tl}
% Header information.
%    \begin{macrocode}
\tl_new:Nn \c_msg_fatal_tl   { Fatal~Error }
\tl_new:Nn \c_msg_error_tl   { Error }
\tl_new:Nn \c_msg_warning_tl { Warning }
\tl_new:Nn \c_msg_info_tl    { Info }
%    \end{macrocode}
%\end{macro}    
%\end{macro} 
%\end{macro} 
%\end{macro} 
%    
%\begin{macro}{\c_msg_fatal_text_tl}
%\begin{macro}{\c_msg_help_text_tl}
%\begin{macro}{\c_msg_kernel_bug_text_tl}
%\begin{macro}{\c_msg_kernel_bug_more_text_tl}
%\begin{macro}{\c_msg_no_info_text_tl}
%\begin{macro}{\c_msg_return_text_tl}
% Simple pieces of text for messages.
%    \begin{macrocode}
\tl_new:Nn \c_msg_fatal_text_tl {
  This~is~a~fatal~error:~LaTeX~will~abort
}
\tl_new:Nn \c_msg_help_text_tl {
  For~immediate~help~type~H~<return>
}
\tl_new:Nn \c_msg_kernel_bug_text_tl {
  This~is~a~LaTeX~bug:~check~coding!
}
\tl_new:Nn \c_msg_kernel_bug_more_text_tl {
  There~is~a~coding~bug~somewhere~around~here.
  \msg_newline:
  This~probably~needs~examining~by~an~expert.
  \c_msg_return_text_tl
}
\tl_new:Nn \c_msg_no_info_text_tl {
  LaTeX~does~not~know~anything~more~about~this~error,~sorry.
  \c_msg_return_text_tl
}
\tl_new:Nn \c_msg_return_text_tl {
  \msg_two_newlines: 
  Try~typing~<return>~to~proceed.
  \msg_newline:
  If~that~doesn't~work,~type~X~<return>~to~quit
}
%    \end{macrocode}
%\end{macro}    
%\end{macro}
%\end{macro} 
%\end{macro} 
%\end{macro} 
%\end{macro} 
%
%\begin{macro}[aux]{\c_msg_hide_tl<spaces>}
% An empty variable with a number of (category code 11) spaces at the
% end of its name. This is used to push the \TeX\ part of an error
% message ``off the screen''.
%
% No indentation here as \verb*| | is a letter!
%    \begin{macrocode}
\group_begin:
\char_make_letter:N\ %
\tl_to_lowercase:n{%
\group_end:%
\tl_new:Nn%
\c_msg_hide_tl                                                         %
{}%
}%
%    \end{macrocode}
%\end{macro}
%
%\begin{macro}{\c_msg_on_line_tl}
% Text for ``on line''.
%    \begin{macrocode}
\tl_new:Nn \c_msg_on_line_tl { on~line }
%    \end{macrocode}
%\end{macro}
%
%\begin{macro}{\c_msg_text_prefix_tl}
%\begin{macro}{\c_msg_more_text_prefix_tl}
% Prefixes for storage areas.
%    \begin{macrocode}
\tl_new:Nn \c_msg_text_prefix_tl      { msg_text ~>~ }
\tl_new:Nn \c_msg_more_text_prefix_tl { msg_text_more ~>~ }
%    \end{macrocode}
%\end{macro}
%\end{macro}
%
%\begin{macro}{\l_msg_class_tl}
%\begin{macro}{\l_msg_current_class_tl}
% For holding the current message method and that for redirection.
%    \begin{macrocode}
\tl_new:N \l_msg_class_tl
\tl_new:N \l_msg_current_class_tl
%    \end{macrocode}
%\end{macro}
%\end{macro}
%
%\begin{macro}{\l_msg_names_clist}
% Lists used for filtering.
%    \begin{macrocode}
\clist_new:N \l_msg_names_clist
%    \end{macrocode}
%\end{macro}
%
%\begin{macro}{\l_msg_redirect_classes_prop}
%\begin{macro}{\l_msg_redirect_names_prop}
% For filtering messages, a list of all messages and of those which have
% to be modified is required.
%    \begin{macrocode}
\prop_new:N \l_msg_redirect_classes_prop
\prop_new:N \l_msg_redirect_names_prop
%    \end{macrocode}
%\end{macro}
%\end{macro}
%\begin{macro}{\l_msg_redirect_classes_clist}
% To prevent an infinite loop.
%    \begin{macrocode}
\clist_new:N \l_msg_redirect_classes_clist
%    \end{macrocode}
%\end{macro}
%
% \subsection{Output helper functions}
%
%\begin{macro}{\msg_line_number:}
%\begin{macro}{\msg_line_context:}
% For writing the line number nicely.
%    \begin{macrocode}
\cs_new_nopar:Npn \msg_line_number: {
  \toks_use:N \tex_inputlineno:D
}
\cs_new_nopar:Npn \msg_line_context: {
  \c_msg_on_line_tl
  \msg_space:
  \msg_line_number:
}
%    \end{macrocode}
%\end{macro}
%\end{macro}
%
%\begin{macro}{\msg_newline:}
%\begin{macro}{\msg_two_newlines:}
% Always forces a new line.
%    \begin{macrocode}
\cs_new_nopar:Npn \msg_newline:      { ^^J }
\cs_new_nopar:Npn \msg_two_newlines: { ^^J ^^J }
%    \end{macrocode}
%\end{macro}
%\end{macro}
%    
%\begin{macro}{\msg_space:}
%\begin{macro}{\msg_two_spaces:}
%\begin{macro}{\msg_four_spaces:}
% For printing spaces, some very simple functions.
%    \begin{macrocode}
\cs_new_nopar:Npn \msg_space:       { ~ }
\cs_new_nopar:Npn \msg_two_spaces:  { \msg_space: \msg_space: }
\cs_new_nopar:Npn \msg_four_spaces: { 
  \msg_two_spaces: \msg_two_spaces: 
}
%    \end{macrocode}
%\end{macro}
%\end{macro}
%\end{macro}
%
%\subsection{Generic functions}
%
% The lowest level functions make no assumptions about modules, 
% \emph{etc.}
%
%\begin{macro}{\msg_generic_new:nnn}
%\begin{macro}{\msg_generic_new:nn}
% Creating a new message is basically the same as the non-checking
% version, and so after a check everything hands over.
%    \begin{macrocode}
\cs_new_nopar:Npn \msg_generic_new:nnn #1 {  
  \chk_if_free_cs:c { \c_msg_text_prefix_tl #1 :xxxx }
  \msg_generic_set:nnn {#1}
}
\cs_new_nopar:Npn \msg_generic_new:nn #1 {  
  \chk_if_free_cs:c { \c_msg_text_prefix_tl #1 :xxxx }
  \msg_generic_set:nn {#1}
}
%    \end{macrocode}
%\end{macro}
%\end{macro}
%
%\begin{macro}{\msg_generic_set:nnn}
%\begin{macro}{\msg_generic_set:nn}
%\begin{macro}[aux]{\msg_generic_set_clist:n}
%\begin{macro}[aux]{\msg_generic_set_text:n}
%\begin{macro}[aux]{\msg_generic_set_more_text:n}
% Creating a message is quite simple. There must be a short text part,
% while the longer text may or may not be available.
%    \begin{macrocode}
\cs_new_nopar:Npn \msg_generic_set:nnn #1 { 
  \msg_generic_set_clist:n {#1}  
  \char_make_space:N \ 
  \msg_generic_set_more_text:nnn {#1} 
}
\cs_new_nopar:Npn \msg_generic_set:nn #1 {  
  \msg_generic_set_clist:n {#1}  
  \char_make_space:N \
  \msg_generic_set_text:nn {#1}
}
\cs_new_nopar:Npn \msg_generic_set_clist:n #1 {
  \clist_if_in:NnF \l_msg_names_clist { // #1 / } {
    \clist_put_right:Nn \l_msg_names_clist { // #1 / }
  }  
}
\cs_new:Npn \msg_generic_set_text:nn  #1#2 {
  \cs_set:cpn { \c_msg_text_prefix_tl #1 :xxxx } ##1##2##3##4 {#2}
  \cs_set_eq:cN { \c_msg_more_text_prefix_tl #1 :xxxx } \c_undefined
  \char_make_ignore:N \ 
}
\cs_new:Npn \msg_generic_set_more_text:nnn #1#2#3 {
  \cs_set:cpn { \c_msg_text_prefix_tl #1 :xxxx } ##1##2##3##4 {#2}
  \cs_set:cpn { \c_msg_more_text_prefix_tl #1 :xxxx } ##1##2##3##4 {#3}
  \char_make_ignore:N \  
}
%    \end{macrocode}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%
%\begin{macro}{\msg_direct_interrupt:xxxx}
%\begin{macro}[aux]{\msg_direct_interrupt:n}
% The low-level interruption macro is rather opaque, unfortunately. The 
% idea here is to create a a message which hides all of \TeX's own 
% information by filling the output up with spaces. To achieve this, 
% spaces have to be letters: hence no indentation. The odd 
% \cs{c_msg_hide_tl<spaces>} actually does the hiding: it is the 
% large run of spaces in the name that is important here. The meaning 
% of |\\| is altered so that the explanation text is a simple run 
% whilst the initial error has line-continuation shown.
%    \begin{macrocode}
\group_begin:
  \char_set_lccode:nn {`\&} {`\ } % {
  \char_set_lccode:w `\} = `\ \scan_stop:
  \char_make_active:N \&
  \char_make_letter:N\ %
\tl_to_lowercase:n{%
\group_end:%
\cs_new_protected:Npn\msg_direct_interrupt:xxxx#1#2#3#4{%
\group_begin:%
\cs_set_eq:NN\\\msg_newline:%
\cs_set_eq:NN\ \msg_space:%
\msg_direct_interrupt_aux:n{#4}%
\cs_set_nopar:Npn\\{\msg_newline:#3}%
\tex_errhelp:D\l_msg_tmp_tl%
\cs_set:Npn&{%
\tex_errmessage:D{%
#1\msg_newline:%
#2\msg_two_newlines:%
\c_msg_help_text_tl%
\c_msg_hide_tl                                                         %
}%
}%
&%
\group_end:%
}%
}%
\cs_new:Npn \msg_direct_interrupt_aux:n #1 {
  \tl_if_empty:nTF {#1} {
    \tl_set:Nx \l_msg_tmp_tl { { \c_msg_no_info_text_tl } }
  }{
    \tl_set:Nx \l_msg_tmp_tl { {#1} }
  }
}
%    \end{macrocode}
%\end{macro}
%\end{macro}
%
%\begin{macro}{\msg_direct_log:xx}
%\begin{macro}{\msg_direct_term:xx}
% Printing to the log or terminal without a stop is rather easier.
%    \begin{macrocode}
\cs_new_protected:Npn \msg_direct_log:xx #1#2 {
  \group_begin:
    \cs_set:Npn \\ { \msg_newline: #2 }
    \cs_set_eq:NN \ \msg_space:
    \iow_log:x { #1 \msg_newline: }
  \group_end:
}
\cs_new_protected:Npn \msg_direct_term:xx #1#2 {
  \group_begin:
    \cs_set:Npn \\ { \msg_newline: #2 }
    \cs_set_eq:NN \ \msg_space:
    \iow_term:x { #1 \msg_newline: }
  \group_end:
}
%    \end{macrocode}
%\end{macro}
%\end{macro}
%
%\subsection{General functions}
%
% The main functions for messaging are built around the separation of
% module from the message name. These have short names as they will be
% widely used.
% 
%\begin{macro}{\msg_new:nnnn}
%\begin{macro}{\msg_new:nnn}
%\begin{macro}{\msg_set:nnnn}
%\begin{macro}{\msg_set:nnn}
% For making messages: all aliases.
%    \begin{macrocode}
\cs_new_nopar:Npn \msg_new:nnnn #1#2 {
  \msg_generic_new:nnn { #1 / #2 } 
}
\cs_new_nopar:Npn \msg_new:nnn #1#2 {
  \msg_generic_new:nn { #1 / #2 } 
}
\cs_new_nopar:Npn \msg_set:nnnn #1#2 {
  \msg_generic_set:nnn { #1 / #2 }
}
\cs_new_nopar:Npn \msg_set:nnn #1#2 {
  \msg_generic_set:nn { #1 / #2 } 
}
%    \end{macrocode}
%\end{macro}
%\end{macro} 
%\end{macro}
%\end{macro}
%
%\begin{macro}{\msg_class_new:nn}
%\begin{macro}{\msg_class_set:nn}
% Creating a new class produces three new functions, with varying 
% numbers of arguments. The \cs{msg_class_loop:n} function is set up
% so that redirection will work as desired.
%    \begin{macrocode}
\cs_new_nopar:Npn \msg_class_new:nn #1 {
  \chk_if_free_cs:c { msg_ #1 :nnxxxx }
  \prop_new:c { l_msg_redirect_ #1 _prop }
  \msg_class_set:nn {#1}
}
\cs_new_nopar:Npn \msg_class_set:nn #1#2 {
  \prop_clear:c { l_msg_redirect_ #1 _prop }
  \cs_set_protected:cpn { msg_ #1 :nnxxxx } ##1##2##3##4##5##6 {
    \msg_use:nnnnxxxx {#1} {#2} {##1} {##2} {##3} {##4} {##5} {##6}
  }
  \cs_set_protected:cpx { msg_ #1 :nnxxx } ##1##2##3##4##5 {
    \exp_not:c { msg_ #1 :nnxxxx } {##1} {##2} {##3} {##4} {##5} { }
  }
  \cs_set_protected:cpx { msg_ #1 :nnxx } ##1##2##3##4 {
    \exp_not:c { msg_ #1 :nnxxxx } {##1} {##2} {##3} {##4} { } { }
  }
  \cs_set_protected:cpx { msg_ #1 :nnx } ##1##2##3 {
    \exp_not:c { msg_ #1 :nnxxxx } {##1} {##2} {##3} { } { } { }
  }
  \cs_set_protected:cpx { msg_ #1 :nn } ##1##2 {
    \exp_not:c { msg_ #1 :nnxxxx } {##1} {##2} { } { } { } { }
  }
}
%    \end{macrocode}
%\end{macro}
%\end{macro}
%
%\begin{macro}[aux]{\msg_use:nnnnxxxx}
% The main message-using macro creates two auxiliary functions: one
% containing the code for the message, and the second a loop function.
% There is then a hand-off to the system for checking if redirection is
% needed.
%    \begin{macrocode}
\cs_new:Npn \msg_use:nnnnxxxx #1#2#3#4#5#6#7#8 {
  \cs_set_nopar:Npn \msg_use_code: {
    \clist_clear:N \l_msg_redirect_classes_clist
    #2
  }
  \cs_set:Npn \msg_use_loop:n ##1 {
    \clist_if_in:NnTF \l_msg_redirect_classes_clist {#1} {
      \msg_kernel_error:nn { msg } { redirect-loop } {#1}
    }{
      \clist_put_right:Nn \l_msg_redirect_classes_clist {#1}
      \cs_if_exist:cTF { msg_ ##1 :nnxxxx } {
        \use:c { msg_ ##1 :nnxxxx } {#3} {#4} {#5} {#6} {#7} {#8}
      }{
        \msg_kernel_error:nnx { msg } { message-class-unknown } {##1}
      }
    }
  }
  \cs_if_exist:cTF { \c_msg_text_prefix_tl #3 / #4 :xxxx } {
    \msg_use_aux:nnn {#1} {#3} {#4} 
  }{
    \msg_kernel_error:nnxx { msg } { message-unknown } {#3} {#4}
  }
}
%    \end{macrocode}
%\end{macro}
%
%\begin{macro}[aux]{\msg_use_code:}
%\begin{macro}[aux]{\msg_use_loop:}
% Blank definitions are initially created for these functions.
%    \begin{macrocode}
\cs_new_nopar:Npn \msg_use_code: { }
\cs_new:Npn \msg_use_loop:n #1 { }
%    \end{macrocode}
%\end{macro}
%\end{macro}
%
%\begin{macro}[aux]{\msg_use_aux:nnn}
% The first auxiliary macro looks for a match by name: the most 
% restrictive check.
%    \begin{macrocode}
\cs_new_nopar:Npn \msg_use_aux:nnn #1#2#3 {
  \tl_set:Nn \l_msg_current_class_tl  {#1}
  \tl_set:Nn \l_msg_current_module_tl {#2}
  \prop_if_in:NnTF \l_msg_redirect_names_prop { // #2 / #3 / } {
     \msg_use_loop_check:nn { names } { // #2 / #3 / }
  }{
    \msg_use_aux:nn {#1} {#2}
  }
}
%    \end{macrocode}
%\end{macro}
%\begin{macro}[aux]{\msg_use_aux:nn}
% The second function checks for general matches by module or for
% all modules.
%    \begin{macrocode}
\cs_new_nopar:Npn \msg_use_aux:nn #1#2 {
  \prop_if_in:cnTF { l_msg_redirect_ #1 _prop } {#2} {
    \msg_use_loop_check:nn {#1} {#2}
  }{
    \prop_if_in:cnTF { l_msg_redirect_ #1 _prop } { * } {
      \msg_use_loop_check:nn {#1} { * }
    }{
      \msg_use_code:
    }
  }    
}
%    \end{macrocode}
%\end{macro}
%\begin{macro}[aux]{\msg_use_loop_check:nn}
% When checking whether to loop, the same code is needed in a few
% places.
%    \begin{macrocode}
\cs_new:Npn \msg_use_loop_check:nn #1#2 {
  \prop_get:cnN { l_msg_redirect_ #1 _prop } {#2} \l_msg_class_tl
  \tl_if_eq:NNTF \l_msg_current_class_tl \l_msg_class_tl {
    \msg_use_code:
  }{
    \msg_use_loop:n { \l_msg_class_tl }
  }
}
%    \end{macrocode}
%\end{macro}
%
%\begin{macro}{\msg_fatal:nnxxxx}
%\begin{macro}{\msg_fatal:nnxxx}
%\begin{macro}{\msg_fatal:nnxx}
%\begin{macro}{\msg_fatal:nnx}
%\begin{macro}{\msg_fatal:nn}
% For fatal errors, after the error message \TeX\ bails out.
%    \begin{macrocode}
\msg_class_new:nn { fatal } {
  \msg_direct_interrupt:xxxx
    { \c_msg_fatal_tl \msg_two_newlines: } 
    { 
      ( \c_msg_fatal_tl ) \msg_space:
      \use:c { \c_msg_text_prefix_tl #1 / #2 :xxxx } {#3} {#4} {#5} {#6}
    }
    { ( \c_msg_fatal_tl ) \msg_space: }
    { \c_msg_fatal_text_tl }
  \tex_end:D
}
%    \end{macrocode}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%
%\begin{macro}{\msg_error:nnxxxx}
%\begin{macro}{\msg_error:nnxxx}
%\begin{macro}{\msg_error:nnxx}
%\begin{macro}{\msg_error:nnx}
%\begin{macro}{\msg_error:nn}
% For an error, the interrupt routine is called, then any recovery code
% is tried.
%    \begin{macrocode}
\msg_class_new:nn { error } {
  \msg_direct_interrupt:xxxx
    { #1~\c_msg_error_tl \msg_newline: } 
    { 
      ( #1 ) \msg_space:
      \use:c { \c_msg_text_prefix_tl #1 / #2 :xxxx } {#3} {#4} {#5} {#6}
    }
    { ( #1 ) \msg_space: }
    { 
      \cs_if_exist:cTF { \c_msg_more_text_prefix_tl #1 / #2 :xxxx } 
        {
          \use:c { \c_msg_more_text_prefix_tl #1 / #2 :xxxx } 
            {#3} {#4} {#5} {#6}
        }
        { \c_msg_no_info_text_tl }
    }
}
%    \end{macrocode}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%
%\begin{macro}{\msg_warning:nnxxxx}
%\begin{macro}{\msg_warning:nnxxx}
%\begin{macro}{\msg_warning:nnxx}
%\begin{macro}{\msg_warning:nnx}
%\begin{macro}{\msg_warning:nn}
% Warnings are printed to the terminal.
%    \begin{macrocode}
\msg_class_new:nn { warning } {
  \msg_direct_term:xx { 
    \msg_space: #1 ~ \c_msg_warning_tl :~  
    \use:c { \c_msg_text_prefix_tl #1 / #2 :xxxx } {#3} {#4} {#5} {#6}
  }
  { ( #1 ) \msg_two_spaces: }
}
%    \end{macrocode}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%
%\begin{macro}{\msg_info:nnxxxx}
%\begin{macro}{\msg_info:nnxxx}
%\begin{macro}{\msg_info:nnxx}
%\begin{macro}{\msg_info:nnx}
%\begin{macro}{\msg_info:nn}
% Information only goes into the log.
%    \begin{macrocode}
\msg_class_new:nn { info } {
  \msg_direct_log:xx { 
    \msg_space: #1~\c_msg_info_tl :~  
    \use:c { \c_msg_text_prefix_tl #1 / #2 :xxxx } {#3} {#4} {#5} {#6}
  }
  { ( #1 ) \msg_two_spaces: }
}
%    \end{macrocode}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%
%\begin{macro}{\msg_log:nnxxxx}
%\begin{macro}{\msg_log:nnxxx}
%\begin{macro}{\msg_log:nnxx}
%\begin{macro}{\msg_log:nnx}
%\begin{macro}{\msg_log:nn}
%  ``Log'' data is very similar to information, but with no extras 
%  added.
%    \begin{macrocode}
\msg_class_new:nn { log } {
  \msg_direct_log:xx { 
    \use:c { \c_msg_text_prefix_tl #1 / #2 :xxxx } {#3} {#4} {#5} {#6}
  }
  { }
}
%    \end{macrocode}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%
%\begin{macro}{\msg_trace:nnxxxx}
%\begin{macro}{\msg_trace:nnxxx}
%\begin{macro}{\msg_trace:nnxx}
%\begin{macro}{\msg_trace:nnx}
%\begin{macro}{\msg_trace:nn}
%  Trace data is the same as log data, more or less
%    \begin{macrocode}
\msg_class_new:nn { trace } {
  \msg_direct_log:xx { 
    \use:c { \c_msg_text_prefix_tl #1 / #2 :xxxx } {#3} {#4} {#5} {#6}
  }
  { }
}
%    \end{macrocode}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%
%\begin{macro}{\msg_none:nnxxxx}
%\begin{macro}{\msg_none:nnxxx}
%\begin{macro}{\msg_none:nnxx}
%\begin{macro}{\msg_none:nnx}
%\begin{macro}{\msg_none:nn}
% The \texttt{none} message type is needed so that input can be gobbled.
%    \begin{macrocode}
\msg_class_new:nn { none } { }
%    \end{macrocode}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%
%\subsection{Redirection functions}
%
%\begin{macro}{\msg_redirect_class:nn}
% Converts class one into class two.
%    \begin{macrocode}
\cs_new_nopar:Npn \msg_redirect_class:nn #1#2 {
  \prop_put:cnn { l_msg_redirect_ #1 _prop } { * } {#2}
}
%    \end{macrocode}
%\end{macro}
%
%\begin{macro}{\msg_redirect_module:nnn}
% For when all messages of a class should be altered for a given module.
%    \begin{macrocode}
\cs_new_nopar:Npn \msg_redirect_module:nnn #1#2#3 {
  \prop_put:cnn { l_msg_redirect_ #2 _prop } {#1} {#3}
}
%    \end{macrocode}
%\end{macro}
%
%\begin{macro}{\msg_redirect_name:nnn}
% Named message will always use the given class.
%    \begin{macrocode}
\cs_new_nopar:Npn \msg_redirect_name:nnn #1#2#3 {
  \prop_put:Nnn \l_msg_redirect_names_prop { // #1 / #2 / } {#3}
}
%    \end{macrocode}
%\end{macro}
%
%\subsection{Kernel-specific functions}
%
%\begin{macro}{\msg_kernel_new:nnnn}
%\begin{macro}{\msg_kernel_new:nnn}
%\begin{macro}{\msg_kernel_set:nnnn}
%\begin{macro}{\msg_kernel_set:nnn}
% The kernel needs some messages of its own. These are created using
% pre-built functions. Two functions are provided: one more general
% and one which only has the short text part.
%    \begin{macrocode}
\cs_new_nopar:Npn \msg_kernel_new:nnnn #1#2 {
  \msg_new:nnnn { LaTeX } { #1 / #2 }
}
\cs_new_nopar:Npn \msg_kernel_new:nnn #1#2 {
  \msg_new:nnn { LaTeX } { #1 / #2 }
}
\cs_new_nopar:Npn \msg_kernel_set:nnnn #1#2 {
  \msg_set:nnnn { LaTeX } { #1 / #2 }
}
\cs_new_nopar:Npn \msg_kernel_set:nnn #1#2 {
  \msg_set:nnn { LaTeX } { #1 / #2 }
}
%    \end{macrocode}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%
%\begin{macro}[aux]{\msg_kernel_classes_new:n}
% Quickly make the fewer-arguments versions.
%    \begin{macrocode}
\cs_new_nopar:Npn \msg_kernel_classes_new:n #1 {
  \cs_new_protected:cpx { msg_kernel_ #1 :nnxxx } ##1##2##3##4##5 
  {
    \exp_not:c { msg_kernel_ #1 :nnxxxx } 
      {##1} {##2} {##3} {##4} {##5} { }
  }
  \cs_new_protected:cpx { msg_kernel_ #1 :nnxx } ##1##2##3##4 
  {
    \exp_not:c { msg_kernel_ #1 :nnxxxx } 
      {##1} {##2} {##3} {##4} { } { }
  }
  \cs_new_protected:cpx { msg_kernel_ #1 :nnx } ##1##2##3 
  {
    \exp_not:c { msg_kernel_ #1 :nnxxxx } {##1} {##2} {##3} { } { } { }
  }
  \cs_new_protected:cpx { msg_kernel_ #1 :nn } ##1##2 
  {
    \exp_not:c { msg_kernel_ #1 :nnxxxx } {##1} {##2} { } { } { } { }
  }
}
%    \end{macrocode}
%\end{macro}
%
%\begin{macro}{\msg_kernel_fatal:nnxxxx}
%\begin{macro}{\msg_kernel_fatal:nnxxx}
%\begin{macro}{\msg_kernel_fatal:nnxx}
%\begin{macro}{\msg_kernel_fatal:nnx}
%\begin{macro}{\msg_kernel_fatal:nn}
% Fatal kernel errors cannot be re-defined.
%    \begin{macrocode}
\cs_new_protected:Npn \msg_kernel_fatal:nnxxxx #1#2#3#4#5#6 {
  \msg_direct_interrupt:xxxx
    { \c_msg_fatal_tl \msg_two_newlines: } 
    { 
      ( LaTeX ) \msg_space:
      \use:c { \c_msg_text_prefix_tl LaTeX / #1 / #2 :xxxx } 
        {#3} {#4} {#5} {#6}
    }
    { ( LaTeX ) \msg_space: }
    { \c_msg_fatal_text_tl }
  \tex_end:D
}
\msg_kernel_classes_new:n { fatal }
%    \end{macrocode}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%
%\begin{macro}{\msg_kernel_error:nnxxxx}
%\begin{macro}{\msg_kernel_error:nnxxx}
%\begin{macro}{\msg_kernel_error:nnxx}
%\begin{macro}{\msg_kernel_error:nnx}
%\begin{macro}{\msg_kernel_error:nn}
% Neither can kernel errors.
%    \begin{macrocode}
\cs_new_protected:Npn \msg_kernel_error:nnxxxx #1#2#3#4#5#6 {
  \msg_direct_interrupt:xxxx
    { LaTeX~\c_msg_error_tl \msg_newline: } 
    { 
      ( LaTeX ) \msg_space:
      \use:c { \c_msg_text_prefix_tl LaTeX / #1 / #2 :xxxx } 
        {#3} {#4} {#5} {#6}
    }
    { ( LaTeX ) \msg_space: }
    { 
      \cs_if_exist:cTF 
        { \c_msg_more_text_prefix_tl LaTeX / #1 / #2 :xxxx } 
        {
          \use:c { \c_msg_more_text_prefix_tl LaTeX / #1 / #2 :xxxx } 
            {#3} {#4} {#5} {#6}
        }
        { \c_msg_no_info_text_tl }
    }
}
\msg_kernel_classes_new:n { error }
%    \end{macrocode}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%
%\begin{macro}{\msg_kernel_warning:nnxxxx}
%\begin{macro}{\msg_kernel_warning:nnxxx}
%\begin{macro}{\msg_kernel_warning:nnxx}
%\begin{macro}{\msg_kernel_warning:nnx}
%\begin{macro}{\msg_kernel_warning:nn}
%\begin{macro}{\msg_kernel_info:nnxxxx}
%\begin{macro}{\msg_kernel_info:nnxxx}
%\begin{macro}{\msg_kernel_info:nnxx}
%\begin{macro}{\msg_kernel_info:nnx}
%\begin{macro}{\msg_kernel_info:nn}
% Life is much more simple for warnings and information messages, as
% these are just short-cuts to the standard classes.
%    \begin{macrocode}
\cs_new_protected_nopar:Npn \msg_kernel_warning:nnxxxx #1#2 {
  \msg_warning:nnxxxx { LaTeX } { #1 / #2 }
}
\msg_kernel_classes_new:n { warning }
\cs_new_protected_nopar:Npn \msg_kernel_info:nnxxxx #1#2 {
  \msg_info:nnxxxx { LaTeX } { #1 / #2 }
}
\msg_kernel_classes_new:n { info }
%    \end{macrocode}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%\end{macro}
%
% Error messages needed to actually implement the message system
% itself.
%    \begin{macrocode}
\msg_kernel_new:nnnn { msg } { message-unknown } 
  {Unknown message `#2' for module `#1'.}
  {%
    LaTeX was asked to display a message by the `#1' module.\\%
    The message was supposed to be called `#2', but I can't\\%
    find a message with that name.%
    \c_msg_return_text_tl
  }
\msg_kernel_new:nnnn { msg } { message-class-unknown } 
  {Unknown message class `#1'.}
  {%
    You have asked for a message to be redirected to class `#1'.\\%
    The message class `#1' has not been set up:\\%
    perhaps this is a typing error.%
    \c_msg_return_text_tl
  }
\msg_kernel_new:nnnn { msg } { redirect-loop } 
  {Message redirection loop for message class `#1'.}
  {%
    You have asked for a message to be redirected,\\%
    but the redirection instructions form a loop:\\%
    you've lost the message.%
    \c_msg_return_text_tl
  }
%    \end{macrocode}
%    
%\begin{macro}{\msg_kernel_bug:x}
% The \LaTeX\ coding bug error gets re-visited here.
%    \begin{macrocode}
\cs_set_protected:Npn \msg_kernel_bug:x #1 {
  \msg_direct_interrupt:xxxx
    { \c_msg_kernel_bug_text_tl } 
    { !~#1 } 
    { ! }
    { \c_msg_kernel_bug_more_text_tl }
}
%    \end{macrocode}
%\end{macro}
%    
%    \begin{macrocode}
%</initex|package>
%    \end{macrocode}
%
% \end{implementation}
% 
% \PrintIndex