ini files parsing with Parsec library in Haskell

parsing_ini.hs

{-# LANGUAGE ScopedTypeVariables #-}
module Main where

import Text.Parsec
import Text.Parsec.Expr
import qualified Text.Parsec.Token as TT
import qualified Text.Parsec.Language as Lang
import Data.Char
import System.IO

type Parser a = Parsec String () a

type Entry    = (String, String)
type Section  = (String, [Entry])
type IniData  = [Section]

ident::Parser String
ident = many1 (letter <|> digit <|> oneOf "_.,:(){}-#@&*|") >>= return . trim

value::Parser String
value = many (noneOf "\n") >>= return . trim

nameSep::Parser ()
nameSep = try $ do
    space
    notFollowedBy (char '(')

stringSpaces::Parser String
stringSpaces = many (char ' ' <|> char '\t')

inidata::Parser IniData
inidata = spaces >> many section >>= return

entry::Parser Entry
entry = do
          k <- sepBy1 ident nameSep
          stringSpaces
          char '='
          stringSpaces
          v <- value
          spaces
          return ((unwords k), v)

section::Parser Section
section = do
          char '['
          name <- sepBy1 ident nameSep
          char ']'
          stringSpaces
          char '\n'
          spaces
          el <- many entry
          return ((unwords name), el)

trim :: String -> String
trim = f . f
   where f = reverse . dropWhile isSpace

split delim = foldr f [[]]
   where
    f x rest@(r:rs)
      | x == delim  = [delim] : rest
      | otherwise   = (x : r) : rs

removeComments::String -> String
removeComments = foldr (++) [] . filter comment . split '\n'
             where comment []    = False
                   comment (x:_) = (x /= ';') && (x /= '\n')

run_parser :: Parser a -> String -> a
run_parser p str =  case parse p "" str of
    Left err -> error $ "parse error at " ++ (show err)
    Right val  -> val

main :: IO ()
main = do
     s <- readFile "C:\\Program Files (x86)\\Opera\\operaprefs_default.ini"
     --parseTest inidata s
     putStrLn $ unlines $ map show ( run_parser inidata s)