xref: /vim-8.2.3635/runtime/syntax/lhaskell.vim (revision aedfcbe1)
1" Vim syntax file
2" Language:		Haskell with literate comments, Bird style,
3"			TeX style and plain text surrounding
4"			\begin{code} \end{code} blocks
5" Maintainer:		Haskell Cafe mailinglist <[email protected]>
6" Original Author:	Arthur van Leeuwen <[email protected]>
7" Last Change:		2010 Apr 11
8" Version:		1.04
9"
10" Thanks to Ian Lynagh for thoughtful comments on initial versions and
11" for the inspiration for writing this in the first place.
12"
13" This style guesses as to the type of markup used in a literate haskell
14" file and will highlight (La)TeX markup if it finds any
15" This behaviour can be overridden, both glabally and locally using
16" the lhs_markup variable or b:lhs_markup variable respectively.
17"
18" lhs_markup	    must be set to either  tex	or  none  to indicate that
19"		    you always want (La)TeX highlighting or no highlighting
20"		    must not be set to let the highlighting be guessed
21" b:lhs_markup	    must be set to eiterh  tex	or  none  to indicate that
22"		    you want (La)TeX highlighting or no highlighting for
23"		    this particular buffer
24"		    must not be set to let the highlighting be guessed
25"
26"
27" 2004 February 18: New version, based on Ian Lynagh's TeX guessing
28"		    lhaskell.vim, cweb.vim, tex.vim, sh.vim and fortran.vim
29" 2004 February 20: Cleaned up the guessing and overriding a bit
30" 2004 February 23: Cleaned up syntax highlighting for \begin{code} and
31"		    \end{code}, added some clarification to the attributions
32" 2008 July 1:      Removed % from guess list, as it totally breaks plain
33"                   text markup guessing
34" 2009 April 29:    Fixed highlighting breakage in TeX mode,
35"                   thanks to Kalman Noel
36"
37
38
39" For version 5.x: Clear all syntax items
40" For version 6.x: Quit when a syntax file was already loaded
41if version < 600
42  syntax clear
43elseif exists("b:current_syntax")
44  finish
45endif
46
47" First off, see if we can inherit a user preference for lhs_markup
48if !exists("b:lhs_markup")
49    if exists("lhs_markup")
50	if lhs_markup =~ '\<\%(tex\|none\)\>'
51	    let b:lhs_markup = matchstr(lhs_markup,'\<\%(tex\|none\)\>')
52	else
53	    echohl WarningMsg | echo "Unknown value of lhs_markup" | echohl None
54	    let b:lhs_markup = "unknown"
55	endif
56    else
57	let b:lhs_markup = "unknown"
58    endif
59else
60    if b:lhs_markup !~ '\<\%(tex\|none\)\>'
61	let b:lhs_markup = "unknown"
62    endif
63endif
64
65" Remember where the cursor is, and go to upperleft
66let s:oldline=line(".")
67let s:oldcolumn=col(".")
68call cursor(1,1)
69
70" If no user preference, scan buffer for our guess of the markup to
71" highlight. We only differentiate between TeX and plain markup, where
72" plain is not highlighted. The heuristic for finding TeX markup is if
73" one of the following occurs anywhere in the file:
74"   - \documentclass
75"   - \begin{env}       (for env != code)
76"   - \part, \chapter, \section, \subsection, \subsubsection, etc
77if b:lhs_markup == "unknown"
78    if search('\\documentclass\|\\begin{\(code}\)\@!\|\\\(sub\)*section\|\\chapter|\\part','W') != 0
79	let b:lhs_markup = "tex"
80    else
81	let b:lhs_markup = "plain"
82    endif
83endif
84
85" If user wants us to highlight TeX syntax or guess thinks it's TeX, read it.
86if b:lhs_markup == "tex"
87    if version < 600
88	source <sfile>:p:h/tex.vim
89	set isk+=_
90    else
91	runtime! syntax/tex.vim
92	unlet b:current_syntax
93	" Tex.vim removes "_" from 'iskeyword', but we need it for Haskell.
94	setlocal isk+=_
95    endif
96    syntax cluster lhsTeXContainer contains=tex.*Zone,texAbstract
97else
98    syntax cluster lhsTeXContainer contains=.*
99endif
100
101" Literate Haskell is Haskell in between text, so at least read Haskell
102" highlighting
103if version < 600
104    syntax include @haskellTop <sfile>:p:h/haskell.vim
105else
106    syntax include @haskellTop syntax/haskell.vim
107endif
108
109syntax region lhsHaskellBirdTrack start="^>" end="\%(^[^>]\)\@=" contains=@haskellTop,lhsBirdTrack containedin=@lhsTeXContainer
110syntax region lhsHaskellBeginEndBlock start="^\\begin{code}\s*$" matchgroup=NONE end="\%(^\\end{code}.*$\)\@=" contains=@haskellTop,beginCodeBegin containedin=@lhsTeXContainer
111
112syntax match lhsBirdTrack "^>" contained
113
114syntax match beginCodeBegin "^\\begin" nextgroup=beginCodeCode contained
115syntax region beginCodeCode  matchgroup=texDelimiter start="{" end="}"
116
117" Define the default highlighting.
118" For version 5.7 and earlier: only when not done already
119" For version 5.8 and later: only when an item doesn't have highlighting yet
120if version >= 508 || !exists("did_tex_syntax_inits")
121  if version < 508
122    let did_tex_syntax_inits = 1
123    command -nargs=+ HiLink hi link <args>
124  else
125    command -nargs=+ HiLink hi def link <args>
126  endif
127
128  HiLink lhsBirdTrack Comment
129
130  HiLink beginCodeBegin	      texCmdName
131  HiLink beginCodeCode	      texSection
132
133  delcommand HiLink
134endif
135
136" Restore cursor to original position, as it may have been disturbed
137" by the searches in our guessing code
138call cursor (s:oldline, s:oldcolumn)
139
140unlet s:oldline
141unlet s:oldcolumn
142
143let b:current_syntax = "lhaskell"
144
145" vim: ts=8
146