{- |

Module : $Header$

Copyright : (c) Felix Reckers, Uni Bremen 2002-2004

License : similar to LGPL, see HetCATS/LICENSE.txt or LIZENZ.txt

Maintainer : maeder@tzi.de

Stability : provisional

Portability : portable

a very limited Haskell-Parser based on DrIFT's Haskell-Parser

-}

module ParseFile where

import DataP

import CommandP

import ParseLib2

type Import = String

-- result: (datas,imports)

parseInputFile :: FilePath -> String -> Either String ([String],[Import])

parseInputFile fp inp = case (ds,is) of

(Left s, Left s2) -> Left (s++"\n"++s2)

(Left s,Right _) -> Left s

(Right _, Left s) -> Left s

(Right x, Right y) -> Right (x,y)

where datParser = skipUntilOff $ datadecl +++ newtypedecl

ds = case papply (parse datParser) (0,0) ((0,0),inp) of

[(x,_)] -> Right $ map name x

_ -> Left (fp++": wrong parse (data)")

is = case papply (parse allImports) (0,-1) ((0,0),inp) of

[(x,_)] -> Right x

_ -> Left (fp++": wrong parse (imports)")

allImports :: Parser [Import]

allImports = do

symbol "module"

m <- cap

opt (skipNest (symbol "(") (symbol ")") >> return [])

symbol "where"

many (fmap (\_->()) command +++ comment)

is <- many importDecl

return (m:is)

importDecl :: Parser Import

importDecl = do

symbol "import"

q <- fmap (\x->if null x then x else x++" ")

(opt (symbol "qualified"))

i <- cap

asM <- opt (symbol "as" >> cap)

h <- opt (symbol "hiding")

hs <- opt $ importList (symbol "(") (symbol ")")

let asM' = if null asM then "" else (" as " ++ asM)

return (q++i++asM' ++ (if null h then "" else " " ++ h) ++ hs)

importList :: Parser String -> Parser String -> Parser String

importList start finish = let

x = finish

+++ do{l <- importList start finish;

s <- x;

return (l ++ s)}

+++ do{ c <- item; s <- x; return (c : s) }

in do{ s1 <- start; s2 <-x; return (s1 ++ s2)}