" Folding support for LaTeX
"
" Options
" g:LatexBox_Folding - Turn on/off folding
" g:LatexBox_fold_preamble - Turn on/off folding of preamble
" g:LatexBox_fold_parts - Define parts (eq. appendix, frontmatter) to fold
" g:LatexBox_fold_sections - Define section levels to fold
" g:LatexBox_fold_envs - Turn on/off folding of environments
"
" {{{1 Set options
if exists('g:LatexBox_Folding') && g:LatexBox_Folding == 1
setl foldmethod=expr
setl foldexpr=LatexBox_FoldLevel(v:lnum)
setl foldtext=LatexBox_FoldText()
"
" The foldexpr function returns "=" for most lines, which means it can become
" slow for large files. The following is a hack that is based on this reply to
" a discussion on the Vim Developer list:
" http://permalink.gmane.org/gmane.editors.vim.devel/14100
"
augroup FastFold
autocmd!
autocmd InsertEnter *.tex setlocal foldmethod=manual
autocmd InsertLeave *.tex setlocal foldmethod=expr
augroup end
endif
if !exists('g:LatexBox_fold_preamble')
let g:LatexBox_fold_preamble=1
endif
if !exists('g:LatexBox_fold_envs')
let g:LatexBox_fold_envs=1
endif
if !exists('g:LatexBox_fold_parts')
let g:LatexBox_fold_parts=[
\ "appendix",
\ "frontmatter",
\ "mainmatter",
\ "backmatter"
\ ]
endif
if !exists('g:LatexBox_fold_sections')
let g:LatexBox_fold_sections=[
\ "part",
\ "chapter",
\ "section",
\ "subsection",
\ "subsubsection"
\ ]
endif
if !exists('g:LatexBox_fold_toc')
let g:LatexBox_fold_toc=0
endif
if !exists('g:LatexBox_fold_toc_levels')
let g:LatexBox_fold_toc_levels=1
endif
" {{{1 LatexBox_FoldLevel help functions
" This function parses the tex file to find the sections that are to be folded
" and their levels, and then predefines the patterns for optimized folding.
function! s:FoldSectionLevels()
" Initialize
let level = 1
let foldsections = []
" If we use two or more of the *matter commands, we need one more foldlevel
let nparts = 0
for part in g:LatexBox_fold_parts
let i = 1
while i < line("$")
if getline(i) =~ '^\s*\\' . part . '\>'
let nparts += 1
break
endif
let i += 1
endwhile
if nparts > 1
let level = 2
break
endif
endfor
" Combine sections and levels, but ignore unused section commands: If we
" don't use the part command, then chapter should have the highest
" level. If we don't use the chapter command, then section should be the
" highest level. And so on.
let ignore = 1
for part in g:LatexBox_fold_sections
" For each part, check if it is used in the file. We start adding the
" part patterns to the fold sections array whenever we find one.
let partpattern = '^\s*\(\\\|% Fake\)' . part . '\>'
if ignore
let i = 1
while i < line("$")
if getline(i) =~# partpattern
call insert(foldsections, [partpattern, level])
let level += 1
let ignore = 0
break
endif
let i += 1
endwhile
else
call insert(foldsections, [partpattern, level])
let level += 1
endif
endfor
return foldsections
endfunction
" {{{1 LatexBox_FoldLevel
" Parse file to dynamically set the sectioning fold levels
let b:LatexBox_FoldSections = s:FoldSectionLevels()
" Optimize by predefine common patterns
let s:notbslash = '\%(\\\@<!\%(\\\\\)*\)\@<='
let s:notcomment = '\%(\%(\\\@<!\%(\\\\\)*\)\@<=%.*\)\@<!'
let s:envbeginpattern = s:notcomment . s:notbslash . '\\begin\s*{.\{-}}'
let s:envendpattern = s:notcomment . s:notbslash . '\\end\s*{.\{-}}'
let s:foldparts = '^\s*\\\%(' . join(g:LatexBox_fold_parts, '\|') . '\)'
let s:folded = '\(% Fake\|\\\(document\|begin\|end\|'
\ . 'front\|main\|back\|app\|sub\|section\|chapter\|part\)\)'
function! LatexBox_FoldLevel(lnum)
" Check for normal lines first (optimization)
let line = getline(a:lnum)
if line !~ s:folded
return "="
endif
" Fold preamble
if g:LatexBox_fold_preamble == 1
if line =~# '\s*\\documentclass'
return ">1"
elseif line =~# '^\s*\\begin\s*{\s*document\s*}'
return "0"
endif
endif
" Fold parts (\frontmatter, \mainmatter, \backmatter, and \appendix)
if line =~# s:foldparts
return ">1"
endif
" Fold chapters and sections
for [part, level] in b:LatexBox_FoldSections
if line =~# part
return ">" . level
endif
endfor
" Never fold \end{document}
if line =~# '^\s*\\end{document}'
return 0
endif
" Fold environments
if g:LatexBox_fold_envs == 1
if line =~# s:envbeginpattern
return "a1"
elseif line =~# s:envendpattern
return "s1"
endif
endif
" Return foldlevel of previous line
return "="
endfunction
" {{{1 LatexBox_FoldText help functions
function! s:LabelEnv()
let i = v:foldend
while i >= v:foldstart
if getline(i) =~ '^\s*\\label'
return matchstr(getline(i), '^\s*\\label{\zs.*\ze}')
end
let i -= 1
endwhile
return ""
endfunction
function! s:CaptionEnv()
let i = v:foldend
while i >= v:foldstart
if getline(i) =~ '^\s*\\caption'
return matchstr(getline(i), '^\s*\\caption\(\[.*\]\)\?{\zs.\+')
end
let i -= 1
endwhile
return ""
endfunction
function! s:CaptionTable()
let i = v:foldstart
while i <= v:foldend
if getline(i) =~ '^\s*\\caption'
return matchstr(getline(i), '^\s*\\caption\(\[.*\]\)\?{\zs.\+')
end
let i += 1
endwhile
return ""
endfunction
function! s:CaptionFrame(line)
" Test simple variants first
let caption1 = matchstr(a:line,'\\begin\*\?{.*}{\zs.\+\ze}')
let caption2 = matchstr(a:line,'\\begin\*\?{.*}{\zs.\+')
if len(caption1) > 0
return caption1
elseif len(caption2) > 0
return caption2
else
let i = v:foldstart
while i <= v:foldend
if getline(i) =~ '^\s*\\frametitle'
return matchstr(getline(i),
\ '^\s*\\frametitle\(\[.*\]\)\?{\zs.\+')
end
let i += 1
endwhile
return ""
endif
endfunction
" {{{1 LatexBox_FoldText
function! LatexBox_FoldText()
" Initialize
let line = getline(v:foldstart)
let nlines = v:foldend - v:foldstart + 1
let level = ''
let title = 'Not defined'
" Fold level
let level = strpart(repeat('-', v:foldlevel-1) . '*',0,3)
if v:foldlevel > 3
let level = strpart(level, 1) . v:foldlevel
endif
let level = printf('%-3s', level)
" Preamble
if line =~ '\s*\\documentclass'
let title = "Preamble"
endif
" Parts, sections and fakesections
let sections = '\(\(sub\)*section\|part\|chapter\)'
let secpat1 = '^\s*\\' . sections . '\*\?\s*{'
let secpat2 = '^\s*\\' . sections . '\*\?\s*\['
if line =~ '\\frontmatter'
let title = "Frontmatter"
elseif line =~ '\\mainmatter'
let title = "Mainmatter"
elseif line =~ '\\backmatter'
let title = "Backmatter"
elseif line =~ '\\appendix'
let title = "Appendix"
elseif line =~ secpat1 . '.*}'
let title = matchstr(line, secpat1 . '\zs.*\ze}')
elseif line =~ secpat1
let title = matchstr(line, secpat1 . '\zs.*')
elseif line =~ secpat2 . '.*\]'
let title = matchstr(line, secpat2 . '\zs.*\ze\]')
elseif line =~ secpat2
let title = matchstr(line, secpat2 . '\zs.*')
elseif line =~ 'Fake' . sections . ':'
let title = matchstr(line,'Fake' . sections . ':\s*\zs.*')
elseif line =~ 'Fake' . sections
let title = matchstr(line, 'Fake' . sections)
endif
" Environments
if line =~ '\\begin'
" Capture environment name
let env = matchstr(line,'\\begin\*\?{\zs\w*\*\?\ze}')
" Set caption based on type of environment
if env == 'frame'
let label = ''
let caption = s:CaptionFrame(line)
elseif env == 'table'
let label = s:LabelEnv()
let caption = s:CaptionTable()
else
let label = s:LabelEnv()
let caption = s:CaptionEnv()
endif
" If no caption found, check for a caption comment
if caption == ''
let caption = matchstr(line,'\\begin\*\?{.*}\s*%\s*\zs.*')
endif
" Create title based on caption and label
if caption . label == ''
let title = env
elseif label == ''
let title = printf('%-12s%s', env . ':',
\ substitute(caption, '}\s*$', '',''))
elseif caption == ''
let title = printf('%-12s%56s', env, '(' . label . ')')
else
let title = printf('%-12s%-30s %21s', env . ':',
\ strpart(substitute(caption, '}\s*$', '',''),0,34),
\ '(' . label . ')')
endif
endif
let title = strpart(title, 0, 68)
return printf('%-3s %-68s #%5d', level, title, nlines)
endfunction
" {{{1 Footer
" vim:fdm=marker:ff=unix:ts=4:sw=4
