base-4.8.1.0: Basic libraries

Copyright(c) Nils Schweinsberg 2011, (c) George Giorgidze 2011 (c) University Tuebingen 2011
LicenseBSD-style (see the file libraries/base/LICENSE)
Maintainerlibraries@haskell.org
Stabilityexperimental
Portabilityportable
Safe HaskellSafe
LanguageHaskell2010

Control.Monad.Zip

Description

Monadic zipping (used for monad comprehensions)

Synopsis

Documentation

class Monad m => MonadZip m where Source

MonadZip type class. Minimal definition: mzip or mzipWith

Instances should satisfy the laws:

  • Naturality :
liftM (f *** g) (mzip ma mb) = mzip (liftM f ma) (liftM g mb)
  • Information Preservation:
liftM (const ()) ma = liftM (const ()) mb
==>
munzip (mzip ma mb) = (ma, mb)

Minimal complete definition

mzip | mzipWith

Methods

mzip :: m a -> m b -> m (a, b) Source

mzipWith :: (a -> b -> c) -> m a -> m b -> m c Source

munzip :: m (a, b) -> (m a, m b) Source

Instances

MonadZip [] Source 

Methods

mzip :: [a] -> [b] -> [(a, b)] Source

mzipWith :: (a -> b -> c) -> [a] -> [b] -> [c] Source

munzip :: [(a, b)] -> ([a], [b]) Source

MonadZip Identity Source 

Methods

mzip :: Identity a -> Identity b -> Identity (a, b) Source

mzipWith :: (a -> b -> c) -> Identity a -> Identity b -> Identity c Source

munzip :: Identity (a, b) -> (Identity a, Identity b) Source