{-# LANGUAGE CPP, TypeSynonymInstances #-}

{- |

Module : $Header$

Description : Interface to the Xml Parsing Facility

Copyright : (c) Ewaryst Schulz, DFKI 2009

License : GPLv2 or higher, see LICENSE.txt

Maintainer : ewaryst.schulz@dfki.de

Stability : provisional

Portability : portable

Provides an xml parse function which depends on external libraries.

-}

module Common.XmlParser (XmlParseable (parseXml), readXmlFile) where

import Text.XML.Light

#ifdef HEXPAT

import qualified Data.ByteString.Lazy as BS

import qualified Common.XmlExpat as XE

#else

#ifdef XMLBS

import qualified Data.ByteString.Lazy as BS

#endif

#endif

-- | This class provides an xml parsing function which is instantiated

-- by using the hexpat or the XML.Light library, dependent on the haskell

-- environment.

class XmlParseable a where

parseXml :: a -> Either Element String

#ifdef HEXPAT

instance XmlParseable BS.ByteString where

parseXml = XE.parseXml

readXmlFile :: FilePath -> IO BS.ByteString

readXmlFile = BS.readFile

-- 169MB on Basic/Algebra_I

#else

#ifdef XMLBS

instance XmlParseable BS.ByteString where

parseXml s = case parseXMLDoc s of

Just x -> Left x

_ -> Right "parseXMLDoc: parse error"

readXmlFile :: FilePath -> IO BS.ByteString

readXmlFile = BS.readFile

-- 426MB on Basic/Algebra_I

#else

instance XmlParseable String where

parseXml s = case parseXMLDoc s of

Just x -> Left x

_ -> Right "parseXMLDoc: parse error"

readXmlFile :: FilePath -> IO String

readXmlFile = readFile

-- 482MB on Basic/Algebra_I

#endif

#endif