summaryrefslogtreecommitdiff
path: root/runtime/autoload/dist/ft.vim
blob: 4ea13f5ba75482efc9e53b33f4fdb0d5a0f3aa24 (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
vim9script

# Vim functions for file type detection
#
# Maintainer:	Bram Moolenaar <Bram@vim.org>
# Last Change:	2022 Feb 22

# These functions are moved here from runtime/filetype.vim to make startup
# faster.

export def Check_inp()
  if getline(1) =~ '^\*'
    setf abaqus
  else
    var n = 1
    var nmax = line("$") > 500 ? 500 : line("$")
    while n <= nmax
      if getline(n) =~? "^header surface data"
	setf trasys
	break
      endif
      n += 1
    endwhile
  endif
enddef

# This function checks for the kind of assembly that is wanted by the user, or
# can be detected from the first five lines of the file.
export def FTasm()
  # make sure b:asmsyntax exists
  if !exists("b:asmsyntax")
    b:asmsyntax = ""
  endif

  if b:asmsyntax == ""
    FTasmsyntax()
  endif

  # if b:asmsyntax still isn't set, default to asmsyntax or GNU
  if b:asmsyntax == ""
    if exists("g:asmsyntax")
      b:asmsyntax = g:asmsyntax
    else
      b:asmsyntax = "asm"
    endif
  endif

  exe "setf " .. fnameescape(b:asmsyntax)
enddef

export def FTasmsyntax()
  # see if the file contains any asmsyntax=foo overrides. If so, change
  # b:asmsyntax appropriately
  var head = " " .. getline(1) .. " " .. getline(2) .. " "
	.. getline(3) .. " " .. getline(4) ..  " " .. getline(5) .. " "
  var match = matchstr(head, '\sasmsyntax=\zs[a-zA-Z0-9]\+\ze\s')
  if match != ''
    b:asmsyntax = match
  elseif ((head =~? '\.title') || (head =~? '\.ident') || (head =~? '\.macro') || (head =~? '\.subtitle') || (head =~? '\.library'))
    b:asmsyntax = "vmasm"
  endif
enddef

var ft_visual_basic_content = '\cVB_Name\|Begin VB\.\(Form\|MDIForm\|UserControl\)'

# See FTfrm() for Visual Basic form file detection
export def FTbas()
  if exists("g:filetype_bas")
    exe "setf " .. g:filetype_bas
    return
  endif

  # most frequent FreeBASIC-specific keywords in distro files
  var fb_keywords = '\c^\s*\%(extern\|var\|enum\|private\|scope\|union\|byref\|operator\|constructor\|delete\|namespace\|public\|property\|with\|destructor\|using\)\>\%(\s*[:=(]\)\@!'
  var fb_preproc  = '\c^\s*\%(#\a\+\|option\s\+\%(byval\|dynamic\|escape\|\%(no\)\=gosub\|nokeyword\|private\|static\)\>\)'
  var fb_comment  = "^\\s*/'"
  # OPTION EXPLICIT, without the leading underscore, is common to many dialects
  var qb64_preproc = '\c^\s*\%($\a\+\|option\s\+\%(_explicit\|_\=explicitarray\)\>\)'

  var lines = getline(1, min([line("$"), 100]))

  if match(lines, fb_preproc) > -1 || match(lines, fb_comment) > -1 || match(lines, fb_keywords) > -1
    setf freebasic
  elseif match(lines, qb64_preproc) > -1
    setf qb64
  elseif match(lines, ft_visual_basic_content) > -1
    setf vb
  else
    setf basic
  endif
enddef

export def FTbtm()
  if exists("g:dosbatch_syntax_for_btm") && g:dosbatch_syntax_for_btm
    setf dosbatch
  else
    setf btm
  endif
enddef

export def BindzoneCheck(default = '')
  if getline(1) .. getline(2) .. getline(3) .. getline(4)
	  =~ '^; <<>> DiG [0-9.]\+.* <<>>\|$ORIGIN\|$TTL\|IN\s\+SOA'
    setf bindzone
  elseif default != ''
    exe 'setf ' .. default
  endif
enddef

export def FTlpc()
  if exists("g:lpc_syntax_for_c")
    var lnum = 1
    while lnum <= 12
      if getline(lnum) =~# '^\(//\|inherit\|private\|protected\|nosave\|string\|object\|mapping\|mixed\)'
	setf lpc
	return
      endif
      lnum += 1
    endwhile
  endif
  setf c
enddef

export def FTheader()
  if match(getline(1, min([line("$"), 200])), '^@\(interface\|end\|class\)') > -1
    if exists("g:c_syntax_for_h")
      setf objc
    else
      setf objcpp
    endif
  elseif exists("g:c_syntax_for_h")
    setf c
  elseif exists("g:ch_syntax_for_h")
    setf ch
  else
    setf cpp
  endif
enddef

# This function checks if one of the first ten lines start with a '@'.  In
# that case it is probably a change file.
# If the first line starts with # or ! it's probably a ch file.
# If a line has "main", "include", "//" or "/*" it's probably ch.
# Otherwise CHILL is assumed.
export def FTchange()
  var lnum = 1
  while lnum <= 10
    if getline(lnum)[0] == '@'
      setf change
      return
    endif
    if lnum == 1 && (getline(1)[0] == '#' || getline(1)[0] == '!')
      setf ch
      return
    endif
    if getline(lnum) =~ "MODULE"
      setf chill
      return
    endif
    if getline(lnum) =~ 'main\s*(\|#\s*include\|//'
      setf ch
      return
    endif
    lnum += 1
  endwhile
  setf chill
enddef

export def FTent()
  # This function checks for valid cl syntax in the first five lines.
  # Look for either an opening comment, '#', or a block start, '{".
  # If not found, assume SGML.
  var lnum = 1
  while lnum < 6
    var line = getline(lnum)
    if line =~ '^\s*[#{]'
      setf cl
      return
    elseif line !~ '^\s*$'
      # Not a blank line, not a comment, and not a block start,
      # so doesn't look like valid cl code.
      break
    endif
    lnum += 1
  endw
  setf dtd
enddef

export def ExCheck()
  var lines = getline(1, min([line("$"), 100]))
  if exists('g:filetype_euphoria')
    exe 'setf ' .. g:filetype_euphoria
  elseif match(lines, '^--\|^ifdef\>\|^include\>') > -1
    setf euphoria3
  else
    setf elixir
  endif
enddef

export def EuphoriaCheck()
  if exists('g:filetype_euphoria')
    exe 'setf ' .. g:filetype_euphoria
  else
    setf euphoria3
  endif
enddef

export def DtraceCheck()
  if did_filetype()
    # Filetype was already detected
    return
  endif
  var lines = getline(1, min([line("$"), 100]))
  if match(lines, '^module\>\|^import\>') > -1
    # D files often start with a module and/or import statement.
    setf d
  elseif match(lines, '^#!\S\+dtrace\|#pragma\s\+D\s\+option\|:\S\{-}:\S\{-}:') > -1
    setf dtrace
  else
    setf d
  endif
enddef

export def FTe()
  if exists('g:filetype_euphoria')
    exe 'setf ' .. g:filetype_euphoria
  else
    var n = 1
    while n < 100 && n <= line("$")
      if getline(n) =~ "^\\s*\\(<'\\|'>\\)\\s*$"
	setf specman
	return
      endif
      n += 1
    endwhile
    setf eiffel
  endif
enddef

export def FTfrm()
  if exists("g:filetype_frm")
    exe "setf " .. g:filetype_frm
    return
  endif

  var lines = getline(1, min([line("$"), 5]))

  if match(lines, ft_visual_basic_content) > -1
    setf vb
  else
    setf form
  endif
enddef

# Distinguish between Forth and F#.
# Provided by Doug Kearns.
export def FTfs()
  if exists("g:filetype_fs")
    exe "setf " .. g:filetype_fs
  else
    var line = getline(nextnonblank(1))
    # comments and colon definitions
    if line =~ '^\s*\.\=( ' || line =~ '^\s*\\G\= ' || line =~ '^\\$'
	  \ || line =~ '^\s*: \S'
      setf forth
    else
      setf fsharp
    endif
  endif
enddef

# Distinguish between HTML, XHTML and Django
export def FThtml()
  var n = 1
  while n < 10 && n <= line("$")
    if getline(n) =~ '\<DTD\s\+XHTML\s'
      setf xhtml
      return
    endif
    if getline(n) =~ '{%\s*\(extends\|block\|load\)\>\|{#\s\+'
      setf htmldjango
      return
    endif
    n += 1
  endwhile
  setf FALLBACK html
enddef

# Distinguish between standard IDL and MS-IDL
export def FTidl()
  var n = 1
  while n < 50 && n <= line("$")
    if getline(n) =~ '^\s*import\s\+"\(unknwn\|objidl\)\.idl"'
      setf msidl
      return
    endif
    n += 1
  endwhile
  setf idl
enddef

# Distinguish between "default" and Cproto prototype file. */
export def ProtoCheck(default: string)
  # Cproto files have a comment in the first line and a function prototype in
  # the second line, it always ends in ";".  Indent files may also have
  # comments, thus we can't match comments to see the difference.
  # IDL files can have a single ';' in the second line, require at least one
  # chacter before the ';'.
  if getline(2) =~ '.;$'
    setf cpp
  else
    exe 'setf ' .. default
  endif
enddef

export def FTm()
  if exists("g:filetype_m")
    exe "setf " .. g:filetype_m
    return
  endif

  # excluding end(for|function|if|switch|while) common to Murphi
  var octave_block_terminators = '\<end\%(_try_catch\|classdef\|enumeration\|events\|methods\|parfor\|properties\)\>'

  var objc_preprocessor = '^\s*#\s*\%(import\|include\|define\|if\|ifn\=def\|undef\|line\|error\|pragma\)\>'

  var n = 1
  var saw_comment = 0  # Whether we've seen a multiline comment leader.
  while n < 100
    var line = getline(n)
    if line =~ '^\s*/\*'
      # /* ... */ is a comment in Objective C and Murphi, so we can't conclude
      # it's either of them yet, but track this as a hint in case we don't see
      # anything more definitive.
      saw_comment = 1
    endif
    if line =~ '^\s*//' || line =~ '^\s*@import\>' || line =~ objc_preprocessor
      setf objc
      return
    endif
    if line =~ '^\s*\%(#\|%!\)' || line =~ '^\s*unwind_protect\>' ||
	  \ line =~ '\%(^\|;\)\s*' .. octave_block_terminators
      setf octave
      return
    endif
    # TODO: could be Matlab or Octave
    if line =~ '^\s*%'
      setf matlab
      return
    endif
    if line =~ '^\s*(\*'
      setf mma
      return
    endif
    if line =~ '^\c\s*\(\(type\|var\)\>\|--\)'
      setf murphi
      return
    endif
    n += 1
  endwhile

  if saw_comment
    # We didn't see anything definitive, but this looks like either Objective C
    # or Murphi based on the comment leader. Assume the former as it is more
    # common.
    setf objc
  else
    # Default is Matlab
    setf matlab
  endif
enddef

export def FTmms()
  var n = 1
  while n < 20
    var line = getline(n)
    if line =~ '^\s*\(%\|//\)' || line =~ '^\*'
      setf mmix
      return
    endif
    if line =~ '^\s*#'
      setf make
      return
    endif
    n += 1
  endwhile
  setf mmix
enddef

# This function checks if one of the first five lines start with a dot.  In
# that case it is probably an nroff file: 'filetype' is set and 1 is returned.
export def FTnroff(): number
  if getline(1)[0] .. getline(2)[0] .. getline(3)[0]
    			.. getline(4)[0] .. getline(5)[0] =~ '\.'
    setf nroff
    return 1
  endif
  return 0
enddef

export def FTmm()
  var n = 1
  while n < 20
    if getline(n) =~ '^\s*\(#\s*\(include\|import\)\>\|@import\>\|/\*\)'
      setf objcpp
      return
    endif
    n += 1
  endwhile
  setf nroff
enddef

export def FTpl()
  if exists("g:filetype_pl")
    exe "setf " .. g:filetype_pl
  else
    # recognize Prolog by specific text in the first non-empty line
    # require a blank after the '%' because Perl uses "%list" and "%translate"
    var l = getline(nextnonblank(1))
    if l =~ '\<prolog\>' || l =~ '^\s*\(%\+\(\s\|$\)\|/\*\)' || l =~ ':-'
      setf prolog
    else
      setf perl
    endif
  endif
enddef

export def FTinc()
  if exists("g:filetype_inc")
    exe "setf " .. g:filetype_inc
  else
    var lines = getline(1) .. getline(2) .. getline(3)
    if lines =~? "perlscript"
      setf aspperl
    elseif lines =~ "<%"
      setf aspvbs
    elseif lines =~ "<?"
      setf php
    # Pascal supports // comments but they're vary rarely used for file
    # headers so assume POV-Ray
    elseif lines =~ '^\s*\%({\|(\*\)' || lines =~? ft_pascal_keywords
      setf pascal
    else
      FTasmsyntax()
      if exists("b:asmsyntax")
	exe "setf " .. fnameescape(b:asmsyntax)
      else
	setf pov
      endif
    endif
  endif
enddef

export def FTprogress_cweb()
  if exists("g:filetype_w")
    exe "setf " .. g:filetype_w
    return
  endif
  if getline(1) =~ '&ANALYZE' || getline(3) =~ '&GLOBAL-DEFINE'
    setf progress
  else
    setf cweb
  endif
enddef

export def FTprogress_asm()
  if exists("g:filetype_i")
    exe "setf " .. g:filetype_i
    return
  endif
  # This function checks for an assembly comment the first ten lines.
  # If not found, assume Progress.
  var lnum = 1
  while lnum <= 10 && lnum < line('$')
    var line = getline(lnum)
    if line =~ '^\s*;' || line =~ '^\*'
      FTasm()
      return
    elseif line !~ '^\s*$' || line =~ '^/\*'
      # Not an empty line: Doesn't look like valid assembly code.
      # Or it looks like a Progress /* comment
      break
    endif
    lnum += 1
  endw
  setf progress
enddef

var ft_pascal_comments = '^\s*\%({\|(\*\|//\)'
var ft_pascal_keywords = '^\s*\%(program\|unit\|library\|uses\|begin\|procedure\|function\|const\|type\|var\)\>'

export def FTprogress_pascal()
  if exists("g:filetype_p")
    exe "setf " .. g:filetype_p
    return
  endif
  # This function checks for valid Pascal syntax in the first ten lines.
  # Look for either an opening comment or a program start.
  # If not found, assume Progress.
  var lnum = 1
  while lnum <= 10 && lnum < line('$')
    var line = getline(lnum)
    if line =~ ft_pascal_comments || line =~? ft_pascal_keywords
      setf pascal
      return
    elseif line !~ '^\s*$' || line =~ '^/\*'
      # Not an empty line: Doesn't look like valid Pascal code.
      # Or it looks like a Progress /* comment
      break
    endif
    lnum += 1
  endw
  setf progress
enddef

export def FTpp()
  if exists("g:filetype_pp")
    exe "setf " .. g:filetype_pp
  else
    var line = getline(nextnonblank(1))
    if line =~ ft_pascal_comments || line =~? ft_pascal_keywords
      setf pascal
    else
      setf puppet
    endif
  endif
enddef

export def FTr()
  var max = line("$") > 50 ? 50 : line("$")

  for n in range(1, max)
    # Rebol is easy to recognize, check for that first
    if getline(n) =~? '\<REBOL\>'
      setf rebol
      return
    endif
  endfor

  for n in range(1, max)
    # R has # comments
    if getline(n) =~ '^\s*#'
      setf r
      return
    endif
    # Rexx has /* comments */
    if getline(n) =~ '^\s*/\*'
      setf rexx
      return
    endif
  endfor

  # Nothing recognized, use user default or assume Rexx
  if exists("g:filetype_r")
    exe "setf " .. g:filetype_r
  else
    # Rexx used to be the default, but R appears to be much more popular.
    setf r
  endif
enddef

export def McSetf()
  # Rely on the file to start with a comment.
  # MS message text files use ';', Sendmail files use '#' or 'dnl'
  for lnum in range(1, min([line("$"), 20]))
    var line = getline(lnum)
    if line =~ '^\s*\(#\|dnl\)'
      setf m4  # Sendmail .mc file
      return
    elseif line =~ '^\s*;'
      setf msmessages  # MS Message text file
      return
    endif
  endfor
  setf m4  " Default: Sendmail .mc file
enddef

# Called from filetype.vim and scripts.vim.
export def SetFileTypeSH(name: string)
  if did_filetype()
    # Filetype was already detected
    return
  endif
  if expand("<amatch>") =~ g:ft_ignore_pat
    return
  endif
  if name =~ '\<csh\>'
    # Some .sh scripts contain #!/bin/csh.
    SetFileTypeShell("csh")
    return
  elseif name =~ '\<tcsh\>'
    # Some .sh scripts contain #!/bin/tcsh.
    SetFileTypeShell("tcsh")
    return
  elseif name =~ '\<zsh\>'
    # Some .sh scripts contain #!/bin/zsh.
    SetFileTypeShell("zsh")
    return
  elseif name =~ '\<ksh\>'
    b:is_kornshell = 1
    if exists("b:is_bash")
      unlet b:is_bash
    endif
    if exists("b:is_sh")
      unlet b:is_sh
    endif
  elseif exists("g:bash_is_sh") || name =~ '\<bash\>' || name =~ '\<bash2\>'
    b:is_bash = 1
    if exists("b:is_kornshell")
      unlet b:is_kornshell
    endif
    if exists("b:is_sh")
      unlet b:is_sh
    endif
  elseif name =~ '\<sh\>'
    b:is_sh = 1
    if exists("b:is_kornshell")
      unlet b:is_kornshell
    endif
    if exists("b:is_bash")
      unlet b:is_bash
    endif
  endif
  SetFileTypeShell("sh")
enddef

# For shell-like file types, check for an "exec" command hidden in a comment,
# as used for Tcl.
# Also called from scripts.vim, thus can't be local to this script.
export def SetFileTypeShell(name: string)
  if did_filetype()
    # Filetype was already detected
    return
  endif
  if expand("<amatch>") =~ g:ft_ignore_pat
    return
  endif
  var l = 2
  while l < 20 && l < line("$") && getline(l) =~ '^\s*\(#\|$\)'
    # Skip empty and comment lines.
    l += 1
  endwhile
  if l < line("$") && getline(l) =~ '\s*exec\s' && getline(l - 1) =~ '^\s*#.*\\$'
    # Found an "exec" line after a comment with continuation
    var n = substitute(getline(l), '\s*exec\s\+\([^ ]*/\)\=', '', '')
    if n =~ '\<tclsh\|\<wish'
      setf tcl
      return
    endif
  endif
  exe "setf " .. name
enddef

export def CSH()
  if did_filetype()
    # Filetype was already detected
    return
  endif
  if exists("g:filetype_csh")
    SetFileTypeShell(g:filetype_csh)
  elseif &shell =~ "tcsh"
    SetFileTypeShell("tcsh")
  else
    SetFileTypeShell("csh")
  endif
enddef

var ft_rules_udev_rules_pattern = '^\s*\cudev_rules\s*=\s*"\([^"]\{-1,}\)/*".*'
export def FTRules()
  var path = expand('<amatch>:p')
  if path =~ '/\(etc/udev/\%(rules\.d/\)\=.*\.rules\|\%(usr/\)\=lib/udev/\%(rules\.d/\)\=.*\.rules\)$'
    setf udevrules
    return
  endif
  if path =~ '^/etc/ufw/'
    setf conf  # Better than hog
    return
  endif
  if path =~ '^/\(etc\|usr/share\)/polkit-1/rules\.d'
    setf javascript
    return
  endif
  var config_lines: list<string>
  try
    config_lines = readfile('/etc/udev/udev.conf')
  catch /^Vim\%((\a\+)\)\=:E484/
    setf hog
    return
  endtry
  var dir = expand('<amatch>:p:h')
  for line in config_lines
    if line =~ ft_rules_udev_rules_pattern
      var udev_rules = substitute(line, ft_rules_udev_rules_pattern, '\1', "")
      if dir == udev_rules
	setf udevrules
      endif
      break
    endif
  endfor
  setf hog
enddef

export def SQL()
  if exists("g:filetype_sql")
    exe "setf " .. g:filetype_sql
  else
    setf sql
  endif
enddef

# If the file has an extension of 't' and is in a directory 't' or 'xt' then
# it is almost certainly a Perl test file.
# If the first line starts with '#' and contains 'perl' it's probably a Perl
# file.
# (Slow test) If a file contains a 'use' statement then it is almost certainly
# a Perl file.
export def FTperl(): number
  var dirname = expand("%:p:h:t")
  if expand("%:e") == 't' && (dirname == 't' || dirname == 'xt')
    setf perl
    return 1
  endif
  if getline(1)[0] == '#' && getline(1) =~ 'perl'
    setf perl
    return 1
  endif
  var save_cursor = getpos('.')
  call cursor(1, 1)
  var has_use = search('^use\s\s*\k', 'c', 30) > 0
  call setpos('.', save_cursor)
  if has_use
    setf perl
    return 1
  endif
  return 0
enddef

# Choose context, plaintex, or tex (LaTeX) based on these rules:
# 1. Check the first line of the file for "%&<format>".
# 2. Check the first 1000 non-comment lines for LaTeX or ConTeXt keywords.
# 3. Default to "plain" or to g:tex_flavor, can be set in user's vimrc.
export def FTtex()
  var firstline = getline(1)
  var format: string
  if firstline =~ '^%&\s*\a\+'
    format = tolower(matchstr(firstline, '\a\+'))
    format = substitute(format, 'pdf', '', '')
    if format == 'tex'
      format = 'latex'
    elseif format == 'plaintex'
      format = 'plain'
    endif
  elseif expand('%') =~ 'tex/context/.*/.*.tex'
    format = 'context'
  else
    # Default value, may be changed later:
    format = exists("g:tex_flavor") ? g:tex_flavor : 'plain'
    # Save position, go to the top of the file, find first non-comment line.
    var save_cursor = getpos('.')
    call cursor(1, 1)
    var firstNC = search('^\s*[^[:space:]%]', 'c', 1000)
    if firstNC > 0
      # Check the next thousand lines for a LaTeX or ConTeXt keyword.
      var lpat = 'documentclass\>\|usepackage\>\|begin{\|newcommand\>\|renewcommand\>'
      var cpat = 'start\a\+\|setup\a\+\|usemodule\|enablemode\|enableregime\|setvariables\|useencoding\|usesymbols\|stelle\a\+\|verwende\a\+\|stel\a\+\|gebruik\a\+\|usa\a\+\|imposta\a\+\|regle\a\+\|utilisemodule\>'
      var kwline = search('^\s*\\\%(' .. lpat .. '\)\|^\s*\\\(' .. cpat .. '\)',
			      'cnp', firstNC + 1000)
      if kwline == 1		# lpat matched
	format = 'latex'
      elseif kwline == 2	# cpat matched
	format = 'context'
      endif		# If neither matched, keep default set above.
      # let lline = search('^\s*\\\%(' . lpat . '\)', 'cn', firstNC + 1000)
      # let cline = search('^\s*\\\%(' . cpat . '\)', 'cn', firstNC + 1000)
      # if cline > 0
      #   let format = 'context'
      # endif
      # if lline > 0 && (cline == 0 || cline > lline)
      #   let format = 'tex'
      # endif
    endif # firstNC
    call setpos('.', save_cursor)
  endif # firstline =~ '^%&\s*\a\+'

  # Translation from formats to file types.  TODO:  add AMSTeX, RevTex, others?
  if format == 'plain'
    setf plaintex
  elseif format == 'context'
    setf context
  else # probably LaTeX
    setf tex
  endif
  return
enddef

export def FTxml()
  var n = 1
  while n < 100 && n <= line("$")
    var line = getline(n)
    # DocBook 4 or DocBook 5.
    var is_docbook4 = line =~ '<!DOCTYPE.*DocBook'
    var is_docbook5 = line =~ ' xmlns="http://docbook.org/ns/docbook"'
    if is_docbook4 || is_docbook5
      b:docbk_type = "xml"
      if is_docbook5
	b:docbk_ver = 5
      else
	b:docbk_ver = 4
      endif
      setf docbk
      return
    endif
    if line =~ 'xmlns:xbl="http://www.mozilla.org/xbl"'
      setf xbl
      return
    endif
    n += 1
  endwhile
  setf xml
enddef

export def FTy()
  var n = 1
  while n < 100 && n <= line("$")
    var line = getline(n)
    if line =~ '^\s*%'
      setf yacc
      return
    endif
    if getline(n) =~ '^\s*\(#\|class\>\)' && getline(n) !~ '^\s*#\s*include'
      setf racc
      return
    endif
    n += 1
  endwhile
  setf yacc
enddef

export def Redif()
  var lnum = 1
  while lnum <= 5 && lnum < line('$')
    if getline(lnum) =~ "^\ctemplate-type:"
      setf redif
      return
    endif
    lnum += 1
  endwhile
enddef

# This function is called for all files under */debian/patches/*, make sure not
# to non-dep3patch files, such as README and other text files.
export def Dep3patch()
  if expand('%:t') ==# 'series'
    return
  endif

  for ln in getline(1, 100)
    if ln =~# '^\%(Description\|Subject\|Origin\|Bug\|Forwarded\|Author\|From\|Reviewed-by\|Acked-by\|Last-Updated\|Applied-Upstream\):'
      setf dep3patch
      return
    elseif ln =~# '^---'
      # end of headers found. stop processing
      return
    endif
  endfor
enddef

# This function checks the first 15 lines for appearance of 'FoamFile'
# and then 'object' in a following line.
# In that case, it's probably an OpenFOAM file
export def FTfoam()
    var ffile = 0
    var lnum = 1
    while lnum <= 15
      if getline(lnum) =~# '^FoamFile'
	ffile = 1
      elseif ffile == 1 && getline(lnum) =~# '^\s*object'
	setf foam
	return
      endif
      lnum += 1
    endwhile
enddef

# Determine if a *.tf file is TF mud client or terraform
export def FTtf()
  var numberOfLines = line('$')
  for i in range(1, numberOfLines)
    var currentLine = trim(getline(i))
    var firstCharacter = currentLine[0]
    if firstCharacter !=? ";" && firstCharacter !=? "/" && firstCharacter !=? ""
      setf terraform
      return
    endif
  endfor
  setf tf
enddef


# Uncomment this line to check for compilation errors early
# defcompile