diff options
| -rw-r--r-- | haddock-api/src/Haddock/Interface/ParseModuleHeader.hs | 218 |
1 files changed, 125 insertions, 93 deletions
diff --git a/haddock-api/src/Haddock/Interface/ParseModuleHeader.hs b/haddock-api/src/Haddock/Interface/ParseModuleHeader.hs index 802ea773..32411e9e 100644 --- a/haddock-api/src/Haddock/Interface/ParseModuleHeader.hs +++ b/haddock-api/src/Haddock/Interface/ParseModuleHeader.hs @@ -1,3 +1,4 @@ +{-# LANGUAGE DeriveFunctor #-} {-# OPTIONS_GHC -Wwarn #-} ----------------------------------------------------------------------------- -- | @@ -11,7 +12,8 @@ ----------------------------------------------------------------------------- module Haddock.Interface.ParseModuleHeader (parseModuleHeader) where -import Control.Monad (mplus) +import Control.Applicative (Alternative (..)) +import Control.Monad (ap) import Data.Char import DynFlags import Haddock.Parser @@ -26,34 +28,44 @@ import Haddock.Types parseModuleHeader :: DynFlags -> Maybe Package -> String -> (HaddockModInfo NsRdrName, MDoc NsRdrName) parseModuleHeader dflags pkgName str0 = let - getKey :: String -> String -> (Maybe String,String) - getKey key str = case parseKey key str of - Nothing -> (Nothing,str) - Just (value,rest) -> (Just value,rest) - - (_moduleOpt,str1) = getKey "Module" str0 - (descriptionOpt,str2) = getKey "Description" str1 - (copyrightOpt,str3) = getKey "Copyright" str2 - (licenseOpt,str4) = getKey "License" str3 - (licenceOpt,str5) = getKey "Licence" str4 - (spdxLicenceOpt,str6) = getKey "SPDX-License-Identifier" str5 - (maintainerOpt,str7) = getKey "Maintainer" str6 - (stabilityOpt,str8) = getKey "Stability" str7 - (portabilityOpt,str9) = getKey "Portability" str8 + kvs :: [(String, String)] + str1 :: String + + (kvs, str1) = maybe ([], str0) id $ runP fields str0 + + -- trim whitespaces + trim :: String -> String + trim = dropWhile isSpace . reverse . dropWhile isSpace . reverse + + getKey :: String -> Maybe String + getKey key = fmap trim (lookup key kvs) + + descriptionOpt = getKey "Description" + copyrightOpt = getKey "Copyright" + licenseOpt = getKey "License" + licenceOpt = getKey "Licence" + spdxLicenceOpt = getKey "SPDX-License-Identifier" + maintainerOpt = getKey "Maintainer" + stabilityOpt = getKey "Stability" + portabilityOpt = getKey "Portability" in (HaddockModInfo { hmi_description = parseString dflags <$> descriptionOpt, hmi_copyright = copyrightOpt, - hmi_license = spdxLicenceOpt `mplus` licenseOpt `mplus` licenceOpt, + hmi_license = spdxLicenceOpt <|> licenseOpt <|> licenceOpt, hmi_maintainer = maintainerOpt, hmi_stability = stabilityOpt, hmi_portability = portabilityOpt, hmi_safety = Nothing, hmi_language = Nothing, -- set in LexParseRn hmi_extensions = [] -- also set in LexParseRn - }, parseParas dflags pkgName str9) + }, parseParas dflags pkgName str1) + +------------------------------------------------------------------------------- +-- Small parser to parse module header. +------------------------------------------------------------------------------- --- | This function is how we read keys. +-- | The below is a small parser framework how we read keys. -- -- all fields in the header are optional and have the form -- @@ -72,78 +84,98 @@ parseModuleHeader dflags pkgName str0 = -- -- the value will be "this is a .. description" and the rest will begin -- at "The module comment". -parseKey :: String -> String -> Maybe (String,String) -parseKey key toParse0 = - do - let - (spaces0,toParse1) = extractLeadingSpaces (dropWhile (`elem` ['\r', '\n']) toParse0) - - indentation = spaces0 - afterKey0 <- extractPrefix key toParse1 - let - afterKey1 = extractLeadingSpaces afterKey0 - afterColon0 <- case snd afterKey1 of - ':':afterColon -> return afterColon - _ -> Nothing - let - (_,afterColon1) = extractLeadingSpaces afterColon0 - - return (scanKey True indentation afterColon1) - where - scanKey :: Bool -> String -> String -> (String,String) - scanKey _ _ [] = ([],[]) - scanKey isFirst indentation str = - let - (nextLine,rest1) = extractNextLine str - - accept = isFirst || sufficientIndentation || allSpaces - - sufficientIndentation = case extractPrefix indentation nextLine of - Just (c:_) | isSpace c -> True - _ -> False - - allSpaces = case extractLeadingSpaces nextLine of - (_,[]) -> True - _ -> False - in - if accept - then - let - (scanned1,rest2) = scanKey False indentation rest1 - - scanned2 = case scanned1 of - "" -> if allSpaces then "" else nextLine - _ -> nextLine ++ "\n" ++ scanned1 - in - (scanned2,rest2) - else - ([],str) - - extractLeadingSpaces :: String -> (String,String) - extractLeadingSpaces [] = ([],[]) - extractLeadingSpaces (s@(c:cs)) - | isSpace c = - let - (spaces1,cs1) = extractLeadingSpaces cs - in - (c:spaces1,cs1) - | otherwise = ([],s) - - extractNextLine :: String -> (String,String) - extractNextLine [] = ([],[]) - extractNextLine (c:cs) - | c == '\n' = - ([],cs) - | otherwise = - let - (line,rest) = extractNextLine cs - in - (c:line,rest) - - -- comparison is case-insensitive. - extractPrefix :: String -> String -> Maybe String - extractPrefix [] s = Just s - extractPrefix _ [] = Nothing - extractPrefix (c1:cs1) (c2:cs2) - | toUpper c1 == toUpper c2 = extractPrefix cs1 cs2 - | otherwise = Nothing + +data C = C {-# UNPACK #-} !Int Char + +newtype P a = P { unP :: [C] -> Maybe ([C], a) } + deriving Functor + +instance Applicative P where + pure x = P $ \s -> Just (s, x) + (<*>) = ap + +instance Monad P where + return = pure + m >>= k = P $ \s0 -> do + (s1, x) <- unP m s0 + unP (k x) s1 + +instance Alternative P where + empty = P $ \_ -> Nothing + a <|> b = P $ \s -> unP a s <|> unP b s + +runP :: P a -> String -> Maybe a +runP p input = fmap snd (unP p input') + where + input' = concat + [ zipWith C [0..] l ++ [C (length l) '\n'] + | l <- lines input + ] + +------------------------------------------------------------------------------- +-- +------------------------------------------------------------------------------- + +curInd :: P Int +curInd = P $ \s -> Just . (,) s $ case s of + [] -> 0 + C i _ : _ -> i + +rest :: P String +rest = P $ \cs -> Just ([], [ c | C _ c <- cs ]) + +munch :: (Int -> Char -> Bool) -> P String +munch p = P $ \cs -> + let (xs,ys) = takeWhileMaybe p' cs in Just (ys, xs) + where + p' (C i c) + | p i c = Just c + | otherwise = Nothing + +munch1 :: (Int -> Char -> Bool) -> P String +munch1 p = P $ \s -> case s of + [] -> Nothing + (c:cs) | Just c' <- p' c -> let (xs,ys) = takeWhileMaybe p' cs in Just (ys, c' : xs) + | otherwise -> Nothing + where + p' (C i c) + | p i c = Just c + | otherwise = Nothing + +char :: Char -> P Char +char c = P $ \s -> case s of + [] -> Nothing + (C _ c' : cs) | c == c' -> Just (cs, c) + | otherwise -> Nothing + +skipSpaces :: P () +skipSpaces = P $ \cs -> Just (dropWhile (\(C _ c) -> isSpace c) cs, ()) + +takeWhileMaybe :: (a -> Maybe b) -> [a] -> ([b], [a]) +takeWhileMaybe f = go where + go xs0@[] = ([], xs0) + go xs0@(x:xs) = case f x of + Just y -> let (ys, zs) = go xs in (y : ys, zs) + Nothing -> ([], xs0) + +------------------------------------------------------------------------------- +-- Fields +------------------------------------------------------------------------------- + +field :: Int -> P (String, String) +field i = do + fn <- munch1 $ \_ c -> isAlpha c || c == '-' + skipSpaces + _ <- char ':' + skipSpaces + val <- munch $ \j c -> isSpace c || j > i + return (fn, val) + +fields :: P ([(String, String)], String) +fields = do + skipSpaces + i <- curInd + fs <- many (field i) + r <- rest + return (fs, r) + |