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|
-----------------------------------------------------------------------------
-- |
-- Module : Control.Monad.Signatures
-- Copyright : (c) Ross Paterson 2012
-- License : BSD-style (see the file LICENSE)
--
-- Maintainer : ross@soi.city.ac.uk
-- Stability : experimental
-- Portability : portable
--
-- Signatures for monad operations that require specialized lifting.
-----------------------------------------------------------------------------
module Control.Monad.Signatures (
CallCC, Catch, Listen, Pass
) where
-- | Signature of the @callCC@ operation,
-- introduced in "Control.Monad.Trans.Cont".
type CallCC m a b = ((a -> m b) -> m a) -> m a
-- | Signature of the @catchE@ operation,
-- introduced in "Control.Monad.Trans.Except".
type Catch e m a = m a -> (e -> m a) -> m a
-- | Signature of the @listen@ operation,
-- introduced in "Control.Monad.Trans.Writer".
type Listen w m a = m a -> m (a, w)
-- | Signature of the @pass@ operation,
-- introduced in "Control.Monad.Trans.Writer".
type Pass w m a = m (a, w -> w) -> m a
|
