diff options
Diffstat (limited to 'indent/haskell.vim')
| -rw-r--r-- | indent/haskell.vim | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/indent/haskell.vim b/indent/haskell.vim new file mode 100644 index 00000000..b69a19c2 --- /dev/null +++ b/indent/haskell.vim @@ -0,0 +1,189 @@ +if !exists('g:polyglot_disabled') || index(g:polyglot_disabled, 'haskell') == -1 + +" indentation for haskell +" +" Based on idris indentation +" +" author: raichoo (raichoo@googlemail.com) +" +" Modify g:haskell_indent_if and g:haskell_indent_case to +" change indentation for `if'(default 3) and `case'(default 5). +" Example (in .vimrc): +" > let g:haskell_indent_if = 2 + +if exists('b:did_indent') + finish +endif + +let b:did_indent = 1 + +if !exists('g:haskell_indent_if') + " if bool + " >>>then ... + " >>>else ... + let g:haskell_indent_if = 3 +endif + +if !exists('g:haskell_indent_case') + " case xs of + " >>[] -> ... + " >>(y:ys) -> ... + let g:haskell_indent_case = 2 +endif + +if !exists('g:haskell_indent_let') + " let x = 0 in + " >>>>x + let g:haskell_indent_let = 4 +endif + +if !exists('g:haskell_indent_where') + " where f :: Int -> Int + " >>>>>>f x = x + let g:haskell_indent_where = 6 +endif + +if !exists('g:haskell_indent_do') + " do x <- a + " >>>y <- b + let g:haskell_indent_do = 3 +endif + +if !exists('g:haskell_indent_in') + " let x = 1 + " >in x + let g:haskell_indent_in = 1 +endif + +setlocal indentexpr=GetHaskellIndent() +setlocal indentkeys=!^F,o,O,0\|,0=where,0=in,0=let,0=deriving,0=->,0=\=>,<CR>,0} + +function! GetHaskellIndent() + let l:prevline = getline(v:lnum - 1) + + if l:prevline =~ '^\s*--' + return match(l:prevline, '\S') + endif + + if synIDattr(synID(line("."), col("."), 1), "name") == 'haskellBlockComment' + for l:c in range(v:lnum - 1, 0, -1) + let l:bline = getline(l:c) + if l:bline =~ '{-' + return 1 + match(l:bline, '{-') + endfor + return 1 + endif + + if l:prevline =~ '^\s*$' + return 0 + endif + + let l:line = getline(v:lnum) + + if l:line =~ '\C^\s*\<where\>' + let l:s = match(l:prevline, '\S') + return l:s + &shiftwidth + endif + + if l:line =~ '\C^\s*\<deriving\>' + let l:s = match(l:prevline, '\C\<\(newtype\|data\)\>') + if l:s >= 0 + return l:s + &shiftwidth + endif + endif + + if l:line =~ '\C^\s*\<let\>' + let l:s = match(l:prevline, '\C\<let\>') + if l:s != 0 + return l:s + endif + endif + + if l:line =~ '\C^\s*\<in\>' + let l:s = match(l:prevline, '\C\<let\>') + if l:s >= 0 + return l:s + g:haskell_indent_in + elseif match(l:prevline, '=') > 0 + let l:s = match(l:prevline, '\S') + return l:s - (4 - g:haskell_indent_in) + endif + endif + + if l:line =~ '^\s*|' + if match(l:prevline, '^\s*data') < 0 + if match(l:prevline, '^\s*|\s') >= 0 + return match(l:prevline, '|') + else + return &shiftwidth + endif + endif + endif + + if l:line =~ '^\s*[=-]>' + let l:s = match(l:prevline, ' :: ') + if l:s >= 0 + return l:s + 1 + endif + endif + + if l:prevline =~ '\s\+[!#$%&*+./<>?@\\^|~-]\+\s*$' + let l:s = match(l:prevline, '\S') + if l:s > 0 + return l:s + &shiftwidth + endif + endif + + if l:prevline =~ '[{([][^})\]]\+$' + return match(l:prevline, '[{([]') + endif + + if l:prevline =~ '\C\<let\>\s\+[^=]\+=\s*$' + return match(l:prevline, '\C\<let\>') + g:haskell_indent_let + &shiftwidth + endif + + if l:prevline =~ '\C\<let\>\s\+.\+\(\<in\>\)\?\s*$' + return match(l:prevline, '\C\<let\>') + g:haskell_indent_let + endif + + if l:prevline !~ '\C\<else\>' + let l:s = match(l:prevline, '\C\<if\>.*\&.*\zs\<then\>') + if l:s > 0 + return l:s + endif + + let l:s = match(l:prevline, '\C\<if\>') + if l:s > 0 + return l:s + g:haskell_indent_if + endif + endif + + if l:prevline =~ '\C\(\<where\>\|\<do\>\|=\|[{([]\)\s*$' + return match(l:prevline, '\S') + &shiftwidth + endif + + if l:prevline =~ '\C\<where\>\s\+\S\+.*$' + return match(l:prevline, '\C\<where\>') + g:haskell_indent_where + endif + + if l:prevline =~ '\C\<do\>\s\+\S\+.*$' + return match(l:prevline, '\C\<do\>') + g:haskell_indent_do + endif + + if l:prevline =~ '\C^\s*\<data\>\s\+[^=]\+\s\+=\s\+\S\+.*$' + if l:line =~ '^\s*|' + return match(l:prevline, '=') + endif + endif + + if l:prevline =~ '\C\<case\>\s\+.\+\<of\>\s*$' + return match(l:prevline, '\C\<case\>') + g:haskell_indent_case + endif + + if l:prevline =~ '\C^\s*\<\data\>\s\+\S\+\s*$' + return match(l:prevline, '\C\<data\>') + &shiftwidth + endif + + return match(l:prevline, '\S') +endfunction + +endif |