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/Haskell 8

Control.Monad.Signatures

Copyright	(c) Ross Paterson 2012
License	BSD-style (see the file LICENSE)
Maintainer	[email protected]
Stability	experimental
Portability	portable
Safe Haskell	Safe
Language	Haskell98

Signatures for monad operations that require specialized lifting. Each signature has a uniformity property that the lifting should satisfy.

type CallCC m a b = ((a -> m b) -> m a) -> m a Source

Signature of the callCC operation, introduced in Control.Monad.Trans.Cont. Any lifting function liftCallCC should satisfy

lift (f k) = f' (lift . k) => lift (cf f) = liftCallCC cf f'

type Catch e m a = m a -> (e -> m a) -> m a Source

Signature of the catchE operation, introduced in Control.Monad.Trans.Except. Any lifting function liftCatch should satisfy

lift (cf m f) = liftCatch (lift . cf) (lift f)

type Listen w m a = m a -> m (a, w) Source

Signature of the listen operation, introduced in Control.Monad.Trans.Writer. Any lifting function liftListen should satisfy

type Pass w m a = m (a, w -> w) -> m a Source

Signature of the pass operation, introduced in Control.Monad.Trans.Writer. Any lifting function liftPass should satisfy