{-# OPTIONS_GHC -fno-warn-orphans #-}
{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE UndecidableInstances #-}
module Control.Monad.Writer.CPS (
Writer,
runWriter,
execWriter,
mapWriter,
WriterT,
writerT,
runWriterT,
execWriterT,
mapWriterT,
module X
) where
import Control.Monad as X
import Control.Monad.Fix as X
import Control.Monad.Trans as X
import Control.Monad.Writer.Class as X
import Data.Monoid as X
import Control.Monad.State.Class
import Control.Monad.Reader.Class
import Control.Monad.Cont.Class
import Control.Monad.Error.Class
import Control.Monad.Trans.Writer.CPS
import qualified Control.Monad.Trans.Writer.CPS as CPS
instance (Monad m, Monoid w) => MonadWriter w (WriterT w m) where
writer = CPS.writer
tell = CPS.tell
listen = CPS.listen
pass = CPS.pass
instance MonadError e m => MonadError e (WriterT w m) where
throwError = lift . throwError
catchError = CPS.liftCatch catchError
instance MonadCont m => MonadCont (WriterT w m) where
callCC = CPS.liftCallCC callCC
instance (MonadReader r m, Monoid w) => MonadReader r (WriterT w m) where
ask = lift ask
local = CPS.mapWriterT . local
reader = lift . reader
instance MonadState s m => MonadState s (WriterT w m) where
get = lift get
put = lift . put
state = lift . state