syntastic/syntax_checkers/lex/flex.vim

"============================================================================
"File:        lex.vim
"Description: Syntax checking plugin for syntastic.vim
"Maintainer:  LCD 47 <lcd047 at gmail dot com>
"License:     This program is free software. It comes without any warranty,
"             to the extent permitted by applicable law. You can redistribute
"             it and/or modify it under the terms of the Do What The Fuck You
"             Want To Public License, Version 2, as published by Sam Hocevar.
"             See http://sam.zoy.org/wtfpl/COPYING for more details.
"
"============================================================================

if exists("g:loaded_syntastic_lex_flex_checker")
    finish
endif
let g:loaded_syntastic_lex_flex_checker = 1

let s:save_cpo = &cpo
set cpo&vim

function! SyntaxCheckers_lex_flex_GetHighlightRegex(item)
    let term = matchstr(a:item['text'],
        \ '\m^\(unrecognized %option\|bad <start condition>\|bad character\( class expression\)\=\): \zs.*')
    if term == ''
        let term = matchstr(a:item['text'],
            \ '\m^\(Definition value for\|undefined definition\) \zs{[^}]\+}\ze')
    endif

    return term != '' ? '\V' . term : ''
endfunction

function! SyntaxCheckers_lex_flex_GetLocList() dict
    let makeprg = self.makeprgBuild({
        \ 'exe': self.getExec() . ' ' . syntastic#c#NullOutput() })

    let errorformat = '%f:%l: %m'

    return SyntasticMake({
        \ 'makeprg': makeprg,
        \ 'errorformat': errorformat })
endfunction

call g:SyntasticRegistry.CreateAndRegisterChecker({
    \ 'filetype': 'lex',
    \ 'name': 'flex'})

let &cpo = s:save_cpo
unlet s:save_cpo