+cHaskell1Version = "5" -- i.e., Haskell 98
+
+-- Default CPP defines in Haskell source
+hsSourceCppOpts =
+ [ "-D__HASKELL1__="++cHaskell1Version
+ , "-D__GLASGOW_HASKELL__="++cProjectVersionInt
+ , "-D__HASKELL98__"
+ , "-D__CONCURRENT_HASKELL__"
+ ]
+
+-----------------------------------------------------------------------------
+-- Reading OPTIONS pragmas
+
+-- This is really very ugly and should be rewritten.
+-- - some error messages are thrown as exceptions (should return)
+-- - we ignore LINE pragmas
+-- - parsing is horrible, combination of prefixMatch and 'read'.
+
+getOptionsFromSource
+ :: String -- input file
+ -> IO [String] -- options, if any
+getOptionsFromSource file
+ = do h <- openFile file ReadMode
+ look h 1 `finally` hClose h
+ where
+ look h i = do
+ r <- tryJust ioErrors (hGetLine h)
+ case r of
+ Left e | isEOFError e -> return []
+ | otherwise -> ioError e
+ Right l' -> do
+ let l = removeSpaces l'
+ case () of
+ () | null l -> look h (i+1)
+ | prefixMatch "#" l -> look h (i+1)
+ | prefixMatch "{-# LINE" l -> look h (i+1) -- -} wrong!
+ | Just opts <- matchOptions i file l
+ -> do rest <- look h (i+1)
+ return (opts ++ rest)
+ | otherwise -> return []
+
+getOptionsFromStringBuffer :: StringBuffer -> FilePath -> [(Int,String)]
+getOptionsFromStringBuffer buffer@(StringBuffer _ len _) fn =
+ let
+ ls = lines (lexemeToString buffer len) -- lazy, so it's ok
+ in
+ look 1 ls
+ where
+ look i [] = []
+ look i (l':ls) = do
+ let l = removeSpaces l'
+ case () of
+ () | null l -> look (i+1) ls
+ | prefixMatch "#" l -> look (i+1) ls
+ | prefixMatch "{-# LINE" l -> look (i+1) ls -- -} wrong!
+ | Just opts <- matchOptions i fn l
+ -> zip (repeat i) opts ++ look (i+1) ls
+ | otherwise -> []
+
+-- detect {-# OPTIONS_GHC ... #-}. For the time being, we accept OPTIONS
+-- instead of OPTIONS_GHC, but that is deprecated.
+matchOptions i fn s
+ | Just s1 <- maybePrefixMatch "{-#" s -- -}
+ = matchOptions1 i fn (removeSpaces s1)
+ | otherwise
+ = Nothing
+ where
+ matchOptions1 i fn s
+ | Just s2 <- maybePrefixMatch "OPTIONS" s
+ = case () of
+ _ | Just s3 <- maybePrefixMatch "_GHC" s2, not (is_ident (head s3))
+ -> matchOptions2 i fn s3
+ | not (is_ident (head s2))
+ -> matchOptions2 i fn s2
+ | otherwise
+ -> Just [] -- OPTIONS_anything is ignored, not treated as start of source
+ | Just s2 <- maybePrefixMatch "INCLUDE" s, not (is_ident (head s2)),
+ Just s3 <- maybePrefixMatch "}-#" (reverse s2)
+ = Just ["-#include", removeSpaces (reverse s3)]
+
+ | Just s2 <- maybePrefixMatch "LANGUAGE" s, not (is_ident (head s2)),
+ Just s3 <- maybePrefixMatch "}-#" (reverse s2)
+ = case [ exts | (exts,"") <- reads ('[' : reverse (']':s3))] of
+ [] -> languagePragParseError i fn
+ exts:_ -> case extensionsToGHCFlag exts of
+ ([], opts) -> Just opts
+ (unsup,_) -> unsupportedExtnError i fn unsup
+ | otherwise = Nothing
+ matchOptions2 i fn s
+ | Just s3 <- maybePrefixMatch "}-#" (reverse s) = Just (words (reverse s3))
+ | otherwise = Nothing
+
+
+languagePragParseError i fn =
+ pgmError (showSDoc (mkLocMessage loc (
+ text "cannot parse LANGUAGE pragma")))
+ where loc = srcLocSpan (mkSrcLoc (mkFastString fn) i 0)
+
+unsupportedExtnError i fn unsup =
+ pgmError (showSDoc (mkLocMessage loc (
+ text "unsupported extensions: " <>
+ hcat (punctuate comma (map (text.show) unsup)))))
+ where loc = srcLocSpan (mkSrcLoc (mkFastString fn) i 0)
+
+
+optionsErrorMsgs :: [String] -> [(Int,String)] -> FilePath -> Messages
+optionsErrorMsgs unhandled_flags flags_lines filename
+ = (emptyBag, listToBag (map mkMsg unhandled_flags_lines))
+ where
+ unhandled_flags_lines = [ (l,f) | f <- unhandled_flags,
+ (l,f') <- flags_lines, f == f' ]
+ mkMsg (line,flag) =
+ ErrUtils.mkPlainErrMsg (srcLocSpan loc) $
+ text "unknown flag in {-# OPTIONS #-} pragma:" <+> text flag
+ where
+ loc = mkSrcLoc (mkFastString filename) line 0
+ -- ToDo: we need a better SrcSpan here
+