eeee054f1e
Now it's possible to change the character encoding while de-/encoding. Also, it's possible to use any data structure as a source or target of the de-/encoding process. darcs-hash:20090221203100-a4fee-6da31f2e37c30a3f5cd5f10af71984209488bb0b
28 lines
766 B
Haskell
28 lines
766 B
Haskell
{-# LANGUAGE FlexibleInstances,MultiParamTypeClasses #-}
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module Control.Throws where
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import Control.Exception.Extensible
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import Control.Monad.Identity
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import Control.Monad.Reader
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import Control.Monad.State
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class Throws e m where
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throwException :: e -> m a
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instance Exception e => Throws e Identity where
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throwException = throw
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{-instance MonadError e m => Throws e m where
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throwException = throwError-}
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instance Throws e (Either e) where
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throwException = Left
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instance Exception e => Throws e IO where
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throwException = throw
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instance Throws e m => Throws e (StateT s m) where
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throwException x = StateT (\s -> throwException x)
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instance Throws e m => Throws e (ReaderT s m) where
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throwException x = ReaderT (\s -> throwException x) |