This file is indexed.

/usr/share/jed/lib/latex.sl is in jed-common 1:0.99.19-7.

This file is owned by root:root, with mode 0o644.

The actual contents of the file can be viewed below.

  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
% latex.sl
%
% AUC-TeX style LaTeX-mode (v0.18) by Kevin Humphreys <kwh@cogsci.ed.ac.uk>
%
% For JED (v0.97.9b) by John E. Davis <davis@space.mit.edu>
%
% Based on AUC-TeX (v9.1i) by Per Abrahamsen <auc_tex_mgr@iesd.auc.dk>
%
% Differences from AUC-TeX 9: - no shell interaction commands
%                             - simplified insert TeX macro (C-c RET)

% ------------------------------------------------------------------------
%
% TO USE THIS MODE: add the line:
%
%    add_mode_for_extension ("latex", "tex");
%
% to your .jedrc file.
%
% To override the default values below, simply declare and initialize
% the approriate variables in your .jedrc file, e.g.,
%
%        variable LaTeX_default_options = "12pt,a4paper";
%        variable LaTeX_default_document_style = "article";
%
% To make LaTeX209 the default set LaTeX_default_documentstyle variable to a
% non-null value (e.g. "article").
%
% Other variables to change in the latex mode hook include:
%
% variable LaTeX_default_documentclass = "article"; % for LaTeX 2e
% variable LaTeX_default_options       = Null_String;
% variable LaTeX_default_section       = "section";
% variable LaTeX_default_environment   = "itemize";
% variable LaTeX_default_figure_label  = "fig:";
% variable LaTeX_default_table_label   = "tab:";
% variable LaTeX_default_section_label = "sec:";
% variable LaTeX_default_documentstyle = Null_String;  % for LaTeX 2.09
% ------------------------------------------------------------------------

% CHANGES HISTORY:
% --- v0.17-1.0
% Fix synchronization of latex_math_mode/latex_mode and made each of the modes
% local to a buffer.  This allows one buffer to be in latex_mode and another
% to be in latex math mode.  --JED
%
% --- v0.17-0.1?
% have indentation recognize \[ \]
%
% PC: changed most of the '\\\\', as they were not necessary
%     added a newline_indent_hook
%     debugged the indent_calculate_last by adding LaTeX_item_indent to
%      the \begin, etc indent level
%     debugged indent_calculate by subtracting LaTeX_item_indent from
%      the \end, etc level
% ---
%     Modified to work with jed0.97-5.
% --- v0.17-0.18
% fixed indent_line to keep the correct cursor position
% --- v0.16-0.17
% added latex_help (C-c i) using latex.texi info file (should be on C-h C-l)
% added completion for documentclass/style, sections, environments
% added tex_complete_symbol (M-TAB) using ltx-comp.dat file
% added simple tex_insert_macro (C-c RET) with completion from ltx-comp.dat
% added tex_current_env for use by tex_mark_environment etc.
% --- v0.15-0.16 (released  2/11/94)
% added insertions for letter class
% used built-in indent_hook for indentation
% added tex_embrace for font specifier insertion using region
% added latex_embrace_env for environment insertion using region
% added latex_change_env for C-c C-e with prefix arg
% made tex_mark_environment more intuitive by doing fsearch first
% --- v0.14-0.15 (released 30/10/94)
% added an attempt to do indentation
% --- v0.13-0.14 (released 27/10/94)
% added option to use latex209 font selections and documentstyle
% added C-c : for uncomment_region and made uncomment_region more robust
% --- v0.12-0.13 (released 25/10/94)
% always pass env to insert_env functions
% fixed insert_figure_env to prompt for center environment
% fixed insert_list_env to insert \item
% --- v0.11-0.12 (first release 20/10/94)
% added math mode
% added all standard environments

%-------------------------------------------------------------------------
% Load the common definitions if not already loaded.  This also defines
% the TeX-Mode syntax table
require ("texcom");

% ----------------------------------------------------------------------------
% Exported global variables
%
custom_variable ("LaTeX_default_documentclass", "article");
custom_variable ("LaTeX_default_options", "");
custom_variable ("LaTeX_default_section", "section");
custom_variable ("LaTeX_default_environment", "itemize");
custom_variable ("LaTeX_default_figure_label", "fig:");
custom_variable ("LaTeX_default_table_label", "tab:");
custom_variable ("LaTeX_default_section_label", "sec:");
custom_variable ("LaTeX_default_documentstyle", "");

%-----------------------------------------------------------------------------
% documentclass/style symbols
variable LaTeX_classes = "book,article,letter,slides,report";
% section symbols
variable LaTeX_sections = "part,chapter,section,subsection,subsubsection,paragraph,subparagraph";
% environment symbols
variable LaTeX_environments = "document,enumerate,itemize,list,trivlist,picture,tabular,array,eqnarray,equation,minipage,description,figure,table,thebibliography,theindex,sloppypar,tabbing,verbatim,flushright,flushleft,displaymath,math,quote,quotation,";
% problems with above line over 255 chars.
LaTeX_environments += "abstract,center,titlepage,verse";

% Load LaTeX-math-mode as required
autoload("latex_toggle_math_mode", "ltx-math");
autoload("latex_math_mode", "ltx-math");

$1 = "LaTeX-Mode";
!if (keymap_p($1)) make_keymap ($1);

% from tex.sl
definekey ("tex_insert_quote", "\"", $1);
definekey ("tex_insert_quote", "'",  $1);
definekey ("tex_blink_dollar", "$",  $1);
definekey ("tex_ldots",        ".",  $1);

% AUC-TeX bindings
definekey_reserved ("tex_insert_braces",       "{",  $1);
definekey_reserved ("tex_font",                "^F", $1);
definekey_reserved ("latex_environment",       "^E", $1);
definekey_reserved ("latex_section",           "^S", $1);
definekey_reserved ("latex_close_environment", "]",  $1);
definekey_reserved ("latex_insert_item",       "^J", $1);
definekey_reserved ("tex_comment_region",      ";",  $1);
definekey_reserved ("tex_uncomment_region",    ":",  $1);
definekey_reserved ("tex_comment_paragraph",   "%",  $1);
definekey_reserved ("tex_mark_environment",    ".",  $1);
definekey_reserved ("tex_mark_section",        "*",  $1);
definekey_reserved ("latex_toggle_math_mode",  "~",  $1);
definekey_reserved ("tex_insert_macro",        "^M", $1);
definekey_reserved ("latex_help",              "i",  $1);

definekey ("tex_complete_symbol",     "\e^I", $1);
% indentation
definekey ("latex_indent_next_line",   "^J",     $1);
definekey_reserved ("latex_indent_region",      "^Q^R", $1);
definekey_reserved ("latex_indent_section",     "^Q^S", $1);
definekey_reserved ("latex_indent_environment", "^Q^E", $1);

% Font Selection - LaTeX2e

define tex_embrace (pre, post)
{
   if (markp())
     {  % if region is set
	check_region (1);
	pop_mark_1 (); insert(pre);
	pop_spot(); insert(post);
	return;
     }
   % if not mid (or end of) word just insert normally
   go_left_1 ();
   if (looking_at_char(' ')
       or looking_at_char('\t')
       or looking_at_char('\n'))
     {
	go_right_1 ();
	insert(pre); push_spot();
     }
   else
     {  % surround word, including any initial '\'
	go_right_1 (); push_spot();
	bskip_word();
	go_left_1 (); !if (looking_at_char('\\')) go_right_1 ();
	insert(pre);
	skip_word();
     }
   insert(post); pop_spot();
}

define tex_insert_font (pre, post, arg)
{
   if (arg == -1)
     {
	tex_embrace(pre, post);
	return;
     }

   % if prefix argument
   push_spot();
   () = bsearch("\\");
   if (looking_at ("\\text")
       or looking_at ("\\emph"))
     {
	delete_word(); del ();
	insert (pre);
     }
   pop_spot ();
}

define tex_delete_font ()
{
   push_spot();
   () = bsearch("\\");
   if (looking_at ("\\text")
       or looking_at ("\\emph"))
     {
	delete_word(); del ();
	() = fsearch_char ('}');
	del ();
     }
   pop_spot ();
}

define tex_font ()
{
   variable arg = prefix_argument(-1);
   variable brace = "}";
   variable ch;
   flush ("\\text??: b(bf) c(sc) e(em) f(sf) i(it) m(md) n r(rm) s(sl) t(tt) u(up)");

   ch = getkey ();
   if (ch > ' ') ch = (ch | 0x20) - 96;
   switch (ch)
     { case 2  : "\\textbf{";}	       % C-b
     { case 3  : "\\textsc{";}	       % C-c
     { case 5  : "\\emph{";}	       % C-e
     { case 6  : "\\textsf{";}	       % C-f
     { case 9  : "\\textit{";}	       % C-i
     { case 13 : "\\textmd{";}	       % C-m
     { case 14 : "\\textnormal{";}     % C-n
     { case 18 : "\\textrm{";}	       % C-r
     { case 19 : "\\textsl{";}	       % C-s
     { case 20 : "\\texttt{";}	       % C-t
     { case 21 : "\\textup{";}	       % C-u
     { case 4  : tex_delete_font (); return; } % C-d
     { beep (); return;}

   tex_insert_font ( (), brace, arg);
   message (Null_String);
}

% Command Insertion

% environments:

% find previous unmatched \begin statement
define tex_current_env ()
{
   variable env = Null_String, count;

   push_mark(); bob(); narrow(); eob ();
   while (bsearch("\\begin{"))
     {
	count = 1;
	push_spot();
	go_right(7);
	push_mark();
	() = ffind_char ('}');
	env = bufsubstr();
	push_spot();
	while (fsearch(sprintf("\\begin{%s}", env)) and down_1 ())
	  count++;
	pop_spot();
	while (fsearch(sprintf("\\end{%s}", env)) and down_1 ())
	  count--;
	pop_spot();
	if (count > 0) break;
     }
   widen();
   return env;
}

define latex_embrace_env(pre, post)
{
   if (markp())
     {
	check_region (0);
	exchange_point_and_mark ();
	insert (pre);
	pop_mark_1 ();
	insert (post);
	%% This was:
	% check_region(1);
	% pop_mark_1 (); insert(pre);
	% pop_spot(); insert(post);
	return;
     }

   insert(pre);
   indent_line (); eol(); push_spot(); newline();
   insert(post); pop_spot();
}

define latex_insert_simple_env (env)
{
   latex_embrace_env(sprintf("\\begin{%s}\n", env),
		     sprintf("\\end{%s}\n", env));
}

define latex_insert_item_env (env)
{
   variable braces = " ";
   !if (strcmp(env, "description")) braces = "[]";
   latex_embrace_env(sprintf("\\begin{%s}\n\\item%s", env, braces),
		     sprintf("\\end{%s}\n", env));
   () = bfind_char (']');
}

define latex_insert_array_env (env)
{
   variable position = read_mini ("Enter Position:", Null_String, "[htbp]");
   variable format = read_mini ("Enter Format:", Null_String, Null_String);
   latex_embrace_env(sprintf("\\begin{%s}%s{%s}\n", env, position, format),
		     sprintf("\\end{%s}\n", env));
}

define latex_insert_label_env (env)
{
   variable label = read_mini ("Enter Label:", Null_String, Null_String);
   if (strcmp(label, Null_String)) label = sprintf("\\label{%s}\n", label);
   latex_embrace_env(sprintf("\\begin{%s}\n%s", env, label),
		     sprintf("\\end{%s}\n", env));
}

define latex_insert_figure_env (env)
{
   variable label_prefix = Null_String;
   switch (env)
     { case "figure"  : label_prefix = LaTeX_default_figure_label; }
     { case "figure*" : label_prefix = LaTeX_default_figure_label; }
     { case "table"   : label_prefix = LaTeX_default_table_label; }
     { case "table*"  : label_prefix = LaTeX_default_table_label; }

   variable position = read_mini ("Enter Position:", Null_String, "[htbp]");

   variable caption = read_mini ("Enter Caption:", Null_String, Null_String);
   if (strcmp(caption, Null_String))
     caption = sprintf("\\caption{%s}\n", caption);

   variable label = read_mini ("Enter Label:", Null_String, label_prefix);
   if (strcmp(label, label_prefix))
     label = sprintf("\\label{%s}\n", label);
   else
     label = Null_String;

   latex_embrace_env(sprintf("\\begin{%s}%s\n", env, position),
		     sprintf("%s%s\\end{%s}\n", caption, label, env));
   push_spot();

   !if (strcmp(env, "figure") and strcmp(env, "figure*"))
     {
	if (get_y_or_n ("Center Figure"))
	  {
	     newline();
	     latex_insert_simple_env ("center");
	     pop_spot(); go_down(2); push_spot();
	  }
     }
   pop_spot();
}

define latex_insert_list_env (env)
{
   variable label = read_mini ("Enter Default Label:", Null_String, Null_String);
   latex_embrace_env(sprintf("\\begin{%s}{%s}{}\n\\item ", env, label),
		     sprintf("\\end{%s}\n", env));
}

define latex_insert_minipage_env (env)
{
   variable position = read_mini ("Enter Position:", Null_String, "[htbp]");
   variable width = read_mini ("Enter Width:", "4cm", Null_String);
   latex_embrace_env(sprintf("\\begin{%s}%s{%s}\n", env, position, width),
		     sprintf("\\end{%s}\n", env));
}

define latex_insert_picture_env (env)
{
   variable width = read_mini ("Enter Width:", Null_String, Null_String);
   variable height = read_mini ("Enter Height:", Null_String, Null_String);
   variable x_offset = read_mini ("Enter X Offset:", "0", Null_String);
   variable y_offset = read_mini ("Enter Y Offset:", "0", Null_String);
   variable offset = Null_String;

   if (strcmp(x_offset, "0") or strcmp(y_offset, "0"))
     offset = sprintf("(%s,%s)", x_offset, y_offset);

   latex_embrace_env(sprintf("\\begin{%s}(%s,%s)%s\n", env, width, height, offset),
		     sprintf("\\end{%s}\n", env));
}

define latex_insert_bib_env (env)
{
   variable label = read_mini ("Enter Label for Bibitem:", Null_String, "99");
   variable blabel = read_mini ("Enter (Optional) Bibitem Label:", Null_String, Null_String);

   if (strlen(blabel)) blabel = sprintf("[%s]", blabel);
   variable key = read_mini ("Enter Key:", Null_String, Null_String);
   latex_embrace_env(sprintf("\\begin{%s}{%s}\n\\bibitem%s{%s}", env, label, blabel, key),
		     sprintf("\\end{%s}\n", env));
}

define latex_insert_letter_args ()
{
   push_spot ();
   insert ("\\address{}\n\\signature{}\n\\begin{letter}{}\n\\opening{}\n\n\n\n\\closing{}\n\\end{letter}");
   pop_spot (); () = ffind_char ('}');
}

define latex_insert_document_env ()
{
   variable class = read_with_completion(LaTeX_classes, "Enter Document Class:", LaTeX_default_documentclass, Null_String, 's');
   variable options = read_mini ("Enter Class Options:", LaTeX_default_options, Null_String);
   if (strlen (options)) options = sprintf("[%s]", options);

   bob ();
   vinsert ("\\documentclass%s{%s}\n\n", options, class);
   insert ("\\begin{document}\n\n\n\n\\end{document}\n"); go_up(3);
   !if (strcmp(class, "letter")) latex_insert_letter_args();
}

define latex_change_env (env)
{
   push_spot();
   variable oldenv = tex_current_env();
   if (strlen(oldenv))
     {
	() = ffind_char ('{');
	go_right_1 (); push_mark();
	() = ffind_char ('}');
	del_region();
	insert(env);
	goto_spot ();
	if (fsearch(sprintf("\\end{%s}", oldenv)))
	  {
	     () = ffind_char ('{');
	     go_right_1 (); push_mark();
	     () = ffind_char ('}');
	     del_region();
	     insert(env);
	  }
     }
   pop_spot();
}

% This function takes a single argument which will ride on the stack
define latex_insert_env ()
{
   dup ();    %  2 copies, 1 for switch and for function

   switch ()
     { case "document"        : pop (); latex_insert_document_env ();}
     { case "enumerate"       : latex_insert_item_env ( () );}
     { case "itemize"         : latex_insert_item_env ( () );}
     { case "list"            : latex_insert_list_env ( () );}
     { case "trivlist"        : latex_insert_item_env ( () );}
     { case "picture"         : latex_insert_picture_env ( () );}
     { case "tabular"         : latex_insert_array_env ( () );}
     { case "tabular*"        : latex_insert_array_env ( () );}
     { case "array"           : latex_insert_array_env ( () );}
     { case "eqnarray"        : latex_insert_label_env ( () );}
     { case "eqnarray*"       : latex_insert_label_env ( () );}
     { case "equation"        : latex_insert_label_env ( () );}
     { case "minipage"        : latex_insert_minipage_env ( () );}
     { case "description"     : latex_insert_item_env ( () );}
     { case "figure"          : latex_insert_figure_env ( () );}
     { case "figure*"         : latex_insert_figure_env ( () );}
     { case "table"           : latex_insert_figure_env ( () );}
     { case "table*"          : latex_insert_figure_env ( () );}
     { case "thebibliography" : latex_insert_bib_env ( () );}
     { case "theindex"        : latex_insert_item_env ( () );}
     {                          latex_insert_simple_env ( () );}
}

define latex_environment ()
{
   variable arg = prefix_argument(-1);
   variable env = LaTeX_default_environment;

   if (bobp) env = "document";
   env = read_with_completion(LaTeX_environments, "Enter Environment Name:", env, Null_String, 's');
   if (strcmp(env, "document")) LaTeX_default_environment = env;

   if (arg == -1)
     latex_insert_env (env);
   else
     latex_change_env (env);
}

define latex_close_environment ()
{
   push_spot ();
   variable env = tex_current_env();
   pop_spot();
   if (strlen (env))
     {
	vinsert ("\\end{%s}\n", env);
     }
}

% sectioning

define latex_section ()
{
   LaTeX_default_section = read_with_completion (LaTeX_sections, "Enter Section Level:", LaTeX_default_section, Null_String, 's');
   variable name = read_mini ("Enter Section Name:", Null_String, Null_String);
   variable label = read_mini ("Enter Label Name:", Null_String, LaTeX_default_section_label);

   eol (); newline ();
   vinsert ("\\%s{%s}\n", LaTeX_default_section, name);
   if (strcmp(label, LaTeX_default_section_label))
     vinsert ("\\label{%s}\n", label);
   newline ();
}

% commenting

define tex_insert_comment ()
{
   variable c = "% ";

   insert(c);
   % Although this appears to be a bizarre way of coding this, I cannot
   % think of a more compact method.
   while (2 == down(2))
     {
	go_up_1 ();
	bol();
	insert(c);
     }
}

define tex_uncomment_region ()
{
   narrow ();
   push_spot_bob ();
   go_down_1 ();
   do
     {
	go_up_1 (); bol();
	if (looking_at("% ")) deln(2);
     }
   while (down(2) == 2);
   pop_spot ();
   widen ();
}

define tex_comment_region ()
{
   if (-1 == prefix_argument (-1))
     {
	narrow ();
	push_spot_bob ();
	tex_insert_comment ();
	pop_spot ();
	widen ();
	return;
     }

   tex_uncomment_region();
}

define tex_comment_paragraph ()
{
   push_spot ();
   if (-1 == prefix_argument (-1))
     {
	forward_paragraph ();
	tex_isolate_paragraph ();   % pushes spot
	pop_spot ();
	bob (); go_down_1 ();
	tex_insert_comment ();
	widen ();
     }
   else
     {
	push_spot (); go_up_1 (); bol();
	while (looking_at("% ")) { deln(2); go_up_1 (); bol(); }
	pop_spot ();
	while (looking_at("% ")) { deln(2); go_down_1 (); }
     }
   pop_spot ();
}

% marking

define tex_mark_environment ()
{
   push_spot();
   variable env = tex_current_env();
   if (strlen (env))
     {
	set_mark_cmd ();
	pop_spot();
	if (fsearch(sprintf("\\end{%s}", env))) go_down_1 ();
	else eob();
     }
   else pop_spot();
}

define tex_mark_section ()
{
   if (re_bsearch ("\\\\[sub]*section"))
     {
	bol(); set_mark_cmd (); go_down_1 ();
	if (re_fsearch ("\\\\[sub]*section")) { go_up_1 ();}
	else eob();
     }
   else if (bsearch ("\\chapter"))
     {
	bol(); set_mark_cmd (); go_down_1 ();
	if (fsearch ("\\chapter")) { go_up_1 ();}
	else eob();
     }
}

% indentation

variable LaTeX_indent_level     = 2;
variable LaTeX_item_indent      = 2;
variable TeX_brace_indent_level = 2;

% This is a useful function that should be made either an intrinsic or
% more available to other packages.
define current_indentation ()
{  % return column of first non-whitespace character
   push_spot();
   bol_skip_white();
   what_column();		       %  left on stack
   pop_spot();
   () - 1;
}

define tex_brace_count_line ()
{  % this will count braces even inside comments
   variable count = 0;
   push_spot_bol ();
   while (ffind_char ('{')) { count += TeX_brace_indent_level; go_right_1 (); }
   bol();
   while (ffind_char ('}')) { count -= TeX_brace_indent_level; go_right_1 (); }
   pop_spot();
   count;
}

define latex_indent_calculate_last () {} % need dummy to allow recursive defn.
define latex_indent_calculate_last ()
{  % return the indentation of the previous normal text

   bol(); if (bobp()) return 0;

   % ignore comments
   do
     {
	go_up_1 (); bol_skip_white();
     }
   while (looking_at_char ('%') and not(bobp()));

   if (looking_at("\\begin{document}")) return current_indentation();

   if (looking_at("\\end{verbatim"))
     {  % skip to before start of verbatim environment
	if (bsearch("\\begin{verbatim"))
	  return latex_indent_calculate_last();
	else
	  return 0;
     }

   if (looking_at("\\begin{") or looking_at("\\left")
       or looking_at ("\\["))
     LaTeX_indent_level + LaTeX_item_indent;
   else if (looking_at("\\item") or looking_at("\\bibitem"))
     LaTeX_item_indent;
   else
     0;

   () + tex_brace_count_line() + current_indentation();
}

define latex_indent_calculate ()
{  % return the indentation of the current text

   bol_skip_white();

   % keep verbatim environments flush left
   if (looking_at("\\begin{verbatim") or looking_at("\\end{verbatim"))
     return 0;

   if (looking_at("\\end{") or looking_at("\\right")
       or looking_at ("\\]"))
     return latex_indent_calculate_last() - LaTeX_item_indent - LaTeX_indent_level;

   if (looking_at("\\item") or looking_at("\\bibitem"))
     return latex_indent_calculate_last() - LaTeX_item_indent;

   latex_indent_calculate_last();
}

define latex_indent_line ()
{
   push_spot();
   latex_indent_calculate();  % on stack
   goto_spot ();
   bol_trim();
   whitespace( () );
   pop_spot();
}

define latex_newline_indent_line ()
{
   if (bolp ())
     {
	newline ();
	return;
     }
   newline();
   latex_indent_line();
   bol_skip_white();
   %eol();
}

define latex_indent_next_line ()
{
   push_spot();
   go_down_1 ();
   latex_indent_line();
   pop_spot();
}

define latex_indent_region ()
{
   check_region(1);
   pop_mark_1 ();
   push_mark();
   latex_indent_line(); % set initial line indentation before narrowing
   pop_spot();

   push_spot();
   go_up_1 ();
   narrow();
   bob();
   while (down_1 ())   % indent line by line (ie slowly)
     latex_indent_line(); % a good latex_format_paragraph would be nice...
   widen();
   pop_spot();
}

define latex_indent_section ()
{
   tex_mark_section();
   latex_indent_region();
}

define latex_indent_environment ()
{
   tex_mark_environment();
   go_down_1 ();
   latex_indent_region();
}

% misc

define tex_insert_braces ()
{
   insert ("{}");
   go_left_1 ();
}

define latex_insert_item ()
{
   eol ();
   insert ("\n\\item ");
   latex_indent_line();
}

% symbol completion

define tex_complete_symbol ()
{
   variable symbol, completion;
   variable insertbuf = whatbuf(), searchbuf = "*ltx-comp*";

   !if (bufferp(searchbuf))
     {
	sw2buf(searchbuf);
	insert_file( expand_jedlib_file("ltx-comp.dat") ); bob();
	set_buffer_modified_flag(0);
	sw2buf(insertbuf);
	bury_buffer(searchbuf);
     }

   push_spot();
   push_mark();
   bskip_word();
   symbol = bufsubstr();

   setbuf(searchbuf);

   !if (bol_fsearch(sprintf("\\%s", symbol))) bob(); % wrap to start

   if (bol_fsearch(sprintf("\\%s", symbol)))
     {
	go_right_1 ();
	go_right(strlen(symbol));
	push_mark_eol();
	completion = bufsubstr();
     }
   else
     {
	setbuf(insertbuf);
	pop_mark_0 ();
	pop_spot();
	error("No completion found");
     }

   setbuf(insertbuf);

   goto_spot ();
   push_mark();
   !if (ffind_char (' ')) eol();
   del_region();
   insert(completion);
   pop_spot();
}

variable LaTeX_macros = Null_String;

define tex_insert_macro ()
{
   variable insertbuf = whatbuf(), searchbuf = "*ltx-comp*";

   !if (strcmp(LaTeX_macros, Null_String))
     {
	!if (bufferp(searchbuf))
	  {
	     sw2buf(searchbuf);
	     insert_file( expand_jedlib_file("ltx-comp.dat") );
	     set_buffer_modified_flag(0);
	     sw2buf(insertbuf);
	     bury_buffer(searchbuf);
	  }
	sw2buf(searchbuf); bob();
	while (bol_fsearch("\\"))
	  {
	     go_right_1 ();
	     push_mark_eol ();
	     LaTeX_macros += bufsubstr() + ",";
	  }
	sw2buf(insertbuf);
     }

   variable macro = read_with_completion (LaTeX_macros, "Enter Macro Name:", Null_String, Null_String, 's');
   vinsert ("\\%s", macro);
   go_left_1 (); !if (looking_at_char('}')) go_right_1 ();
}

% info file interface

variable LaTeX_help = Null_String;

define latex_help ()
{
   variable info_file = "(latex)";
   variable latex_buf = whatbuf(), info_buf = "*Info*";
   push_spot(); variable guess = tex_current_env(); pop_spot();
   !if (strcmp(guess, "document")) guess = Null_String;

   ERROR_BLOCK
     {
	sw2buf(latex_buf);
     }

   !if (strcmp(LaTeX_help, Null_String))
     {
#iffalse
	info_find_node(sprintf("%sList of Commands", info_file));
#else
	info_find_node(sprintf("%sCommands", info_file));
#endif

	sw2buf(info_buf);
	if (fsearch("* Menu:")) go_down_1 ();
	while (bol_fsearch("* "))
	  {
	     go_right(2);
	     push_mark_eol ();
	     go_left(2);
	     LaTeX_help += bufsubstr() + ",";
	  }
     }

   sw2buf(latex_buf);
   push_spot();
   !if (looking_at_char('\\'))
     {
	go_left_1 ();
	!if (looking_at_char('\\'))
	  {
	     goto_spot ();
	     bskip_word(); go_left_1 ();
	  }
     }
   if (looking_at_char('\\'))
     {
	push_mark();
	skip_word();
	guess = bufsubstr();
     }
   pop_spot();

   guess = read_with_completion(LaTeX_help, "Describe LaTeX command:", guess, Null_String, 's');
   info_find_node(sprintf("%s%s", info_file, guess));
   pop2buf(info_buf);
}

private define init_menu (menu)
{
   menu_append_item (menu, "Font", "tex_font");
   menu_append_item (menu, "Environment", "latex_environment");
   menu_append_item (menu, "Section", "latex_section");
   menu_append_item (menu, "Comment Region", "tex_comment_region");
   menu_append_item (menu, "Uncomment Region", "tex_uncomment_region");
   menu_append_item (menu, "Comment Paragraph", "tex_comment_paragraph");
   menu_append_item (menu, "Mark Environment", "tex_mark_environment");
   menu_append_item (menu, "Mark Section", "tex_mark_section");
   menu_append_item (menu, "Indent Region", "latex_indent_region");
   menu_append_item (menu, "Indent Section", "latex_indent_section");
   menu_append_item (menu, "Indent Environment", "latex_indent_environment");
}

%!%+
%\function{latex_mode}
%\synopsis{latex_mode}
%\usage{Void latex_mode ();}
%\description
% This mode is designed to facilitate the task of editing latex files.
% It calls the function \var{latex_mode_hook} if it is defined.  In addition,
% if the abbreviation table \var{"TeX"} is defined, that table is used.
%
% The default key-bindings for this mode include:
%#v+
%    "tex_insert_braces"       "^C{"
%    "tex_font"                "^C^F"
%    "latex_environment"       "^C^E"
%    "latex_section"           "^C^S"
%    "latex_close_environment" "^C]"
%    "latex_insert_item"       "^C^J"
%    "tex_comment_region"      "^C;"
%    "tex_uncomment_region"    "^C:"
%    "tex_comment_paragraph"   "^C%"
%    "tex_mark_environment"    "^C."
%    "tex_mark_section"        "^C*"
%    "latex_toggle_math_mode"  "^C~"
%    "tex_insert_macro"        "^C^M"
%    "tex_complete_symbol"     "\e^I"
%    "latex_help"              "^Ci"
%    "latex_indent_next_line"   "^J"
%    "latex_indent_region"      "^C^Q^R"
%    "latex_indent_section"     "^C^Q^S"
%    "latex_indent_environment" "^C^Q^E"
%#v-
%!%-
define latex_mode ()
{
   variable tex = "TeX";
   variable quote = "`";

   use_keymap ("LaTeX-Mode");
   set_mode ("LaTeX", 0x1 | 0x20);

   set_buffer_hook ("par_sep", "tex_paragraph_separator");
   set_buffer_hook ("wrap_hook", "tex_wrap_hook");
   set_buffer_hook ("indent_hook", "latex_indent_line");
   set_buffer_hook ("newline_indent_hook", "latex_newline_indent_line");

   % latex math mode will map this to something else.
   %local_unsetkey (quote);
   %local_setkey ("quoted_insert", quote);

   mode_set_mode_info ("LaTeX", "init_mode_menu", &init_menu);
   mode_set_mode_info ("LaTeX", "fold_info", "%{{{\r%}}}\r\r");

   use_syntax_table ("TeX-Mode");
   run_mode_hooks("latex_mode_hook");
}

% overload alternative function definitions for LaTeX 2.09 if required
if (strcmp(LaTeX_default_documentstyle, ""))
  () = evalfile("latex209");

provide ("latex");