StylizeLine, take 2

stylizeline.vim

" StylizeLine

" include guard
"if exists("g:loaded_StylizeLine") && g:loaded_StylizeLine
"    finish
"endif
"let g:loaded_StylizeLine = 1

function! StylizeLine(modifyBuffer, lineOffset)
    let l:line = getline(line(".") + a:lineOffset)

    " empty line
    if match(l:line, "^\\s*$") != -1
	call setline(line(".") + a:lineOffset, "")
	return ""
    endif

    " Skip comments and preprocessor directives.
    if (match(l:line, "^\\s*#") != -1) || (match(l:line, "^\\s*\/\/") != -1)
	return l:line
    endif

    " single spaces before and after =+/|%
    let l:line = substitute(l:line, "\\s*\\([=+/|%]\\)\\s*", " \\1 ", "g")

    " single space before -!~
    let l:line = substitute(l:line, "\\s*\\([-!~]\\)", " \\1", "g")

    " increment, and, or, equal, not equal
    let l:line = substitute(l:line, "+\\s*+", "++", "g")
    let l:line = substitute(l:line, "&\\s*&", "&&", "g")
    let l:line = substitute(l:line, "|\\s*|", "||", "g")
    let l:line = substitute(l:line, "=\\s*=", "==", "g")
    let l:line = substitute(l:line, "!\\s*=", "!=", "g")

    " if, for, while
    " let l:line = substitute(l:line, "^\\s*\zsif\\s*(", "if (", "")
    " let l:line = substitute(l:line, "^\\s*\zsfor\\s*(", "for (", "")
    " let l:line = substitute(l:line, "^\\s*\zswhile\\s*(", "while (", "")

    " += etc.
    let l:line = substitute(l:line, "\\s*\\([-!~=+*/&|<>%]\\)\\s*=\\s*", " \\1= ", "g")

    " <<
    let l:line = substitute(l:line, "\\s*<<\\s*", " << ", "g")

    " semicolon and comma
    let l:line = substitute(l:line, "\\s*\\([;,]\\)\\s*", "\\1 ", "g")

    " spaces at EOL
    let l:line = substitute(l:line, "\\s\\+$", "", "")

    if a:modifyBuffer != 0
	call setline(line(".") + a:lineOffset, l:line)
    endif
    return l:line
endfunction

" suggested keymaps
noremap <M-s> :call StylizeLine(1, 0)<CR>
inoremap <silent> <CR> <CR> <BS><ESC>:call StylizeLine(1, -1)<CR>a
inoremap <silent> <M-s> <ESC>:call StylizeLine(1, 0)<CR>A

" eof