X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Fparser%2FHaddockLex.x;fp=compiler%2Fparser%2FHaddockLex.x;h=e4c2d2d933679be01d3bf206156c0eccd7ad4e0e;hb=190f24892156953d73b55401d0467a6f1a88ce5d;hp=0000000000000000000000000000000000000000;hpb=aa8e9422469f1ccb3c52444fa56aae34de799334;p=ghc-hetmet.git diff --git a/compiler/parser/HaddockLex.x b/compiler/parser/HaddockLex.x new file mode 100644 index 0000000..e4c2d2d --- /dev/null +++ b/compiler/parser/HaddockLex.x @@ -0,0 +1,161 @@ +-- +-- Haddock - A Haskell Documentation Tool +-- +-- (c) Simon Marlow 2002 +-- +-- This file was modified and integrated into GHC by David Waern 2006 +-- + +{ +module HaddockLex ( + Token(..), + tokenise + ) where + +import HsSyn +import Lexer hiding (Token) +import Parser ( parseIdentifier ) +import StringBuffer +import OccName +import RdrName +import SrcLoc +import DynFlags +import DynFlags + +import Char +import Numeric +import System.IO.Unsafe +} + +$ws = $white # \n +$digit = [0-9] +$hexdigit = [0-9a-fA-F] +$special = [\"\@\/] +$alphanum = [A-Za-z0-9] +$ident = [$alphanum \'\_\.\!\#\$\%\&\*\+\/\<\=\>\?\@\\\\\^\|\-\~] + +:- + +-- beginning of a paragraph +<0,para> { + $ws* \n ; + $ws* \> { begin birdtrack } + $ws* [\*\-] { token TokBullet `andBegin` string } + $ws* \[ { token TokDefStart `andBegin` def } + $ws* \( $digit+ \) { token TokNumber `andBegin` string } + $ws* { begin string } +} + +-- beginning of a line + { + $ws* \> { begin birdtrack } + $ws* \n { token TokPara `andBegin` para } + -- Here, we really want to be able to say + -- $ws* (\n | ) { token TokPara `andBegin` para} + -- because otherwise a trailing line of whitespace will result in + -- a spurious TokString at the end of a docstring. We don't have , + -- though (NOW I realise what it was for :-). To get around this, we always + -- append \n to the end of a docstring. + () { begin string } +} + + .* \n? { strtoken TokBirdTrack `andBegin` line } + + { + $special { strtoken $ \s -> TokSpecial (head s) } + \<.*\> { strtoken $ \s -> TokURL (init (tail s)) } + \#.*\# { strtoken $ \s -> TokAName (init (tail s)) } + [\'\`] $ident+ [\'\`] { ident } + \\ . { strtoken (TokString . tail) } + "&#" $digit+ \; { strtoken $ \s -> TokString [chr (read (init (drop 2 s)))] } + "&#" [xX] $hexdigit+ \; { strtoken $ \s -> case readHex (init (drop 3 s)) of [(n,_)] -> TokString [chr n] } + -- allow special characters through if they don't fit one of the previous + -- patterns. + [\'\`\<\#\&\\] { strtoken TokString } + [^ $special \< \# \n \'\` \& \\ \]]* \n { strtoken TokString `andBegin` line } + [^ $special \< \# \n \'\` \& \\ \]]+ { strtoken TokString } +} + + { + \] { token TokDefEnd `andBegin` string } +} + +-- ']' doesn't have any special meaning outside of the [...] at the beginning +-- of a definition paragraph. + { + \] { strtoken TokString } +} + +{ +data Token + = TokPara + | TokNumber + | TokBullet + | TokDefStart + | TokDefEnd + | TokSpecial Char + | TokIdent [RdrName] + | TokString String + | TokURL String + | TokAName String + | TokBirdTrack String +-- deriving Show + +-- ----------------------------------------------------------------------------- +-- Alex support stuff + +type StartCode = Int +type Action = String -> StartCode -> (StartCode -> [Token]) -> [Token] + +type AlexInput = (Char,String) + +alexGetChar (_, []) = Nothing +alexGetChar (_, c:cs) = Just (c, (c,cs)) + +alexInputPrevChar (c,_) = c + +tokenise :: String -> [Token] +tokenise str = let toks = go ('\n', eofHack str) para in {-trace (show toks)-} toks + where go inp@(_,str) sc = + case alexScan inp sc of + AlexEOF -> [] + AlexError _ -> error "lexical error" + AlexSkip inp' len -> go inp' sc + AlexToken inp' len act -> act (take len str) sc (\sc -> go inp' sc) + +-- NB. we add a final \n to the string, (see comment in the beginning of line +-- production above). +eofHack str = str++"\n" + +andBegin :: Action -> StartCode -> Action +andBegin act new_sc = \str sc cont -> act str new_sc cont + +token :: Token -> Action +token t = \str sc cont -> t : cont sc + +strtoken :: (String -> Token) -> Action +strtoken t = \str sc cont -> t str : cont sc + +begin :: StartCode -> Action +begin sc = \str _ cont -> cont sc + +-- ----------------------------------------------------------------------------- +-- Lex a string as a Haskell identifier + +ident :: Action +ident str sc cont = + case strToHsQNames id of + Just names -> TokIdent names : cont sc + Nothing -> TokString str : cont sc + where id = init (tail str) + +strToHsQNames :: String -> Maybe [RdrName] +strToHsQNames str0 = + let buffer = unsafePerformIO (stringToStringBuffer str0) + pstate = mkPState buffer noSrcLoc defaultDynFlags + lex = lexer (\t -> return t) + result = unP parseIdentifier pstate + in case result of + POk _ name -> Just [unLoc name] + _ -> Nothing +}