monad-wrap: Wrap functions such as catch around different monads

[ bsd3, control, library ] [ Propose Tags ]

This package allows you to invoke a function on one monadic type passing it an argument of a different monadic type. The canonical example of this is wanting to use a function such as finally :: IO a -> IO a to catch exceptions thrown by a computation x :: ReaderT MyConfig IO b. If x uses the ReaderT function ask, it cannot be re-written to run in the IO monad, and hence cannot be executed with a construction like lift (x `finally` cleanup). Instead, you must use the wrap method, provide by module Control.Monad.Wrap. This package contains two further modules: Control.Monad.MultiWrap implements mwrap, a method that behaves like wrap but allows wrapping through multiple nested layers of monad transformer. The module Control.Monad.MultiLift provides mlift, a version of lift that similarly lifts through multiple nested monad transformers.


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Versions [RSS] 0.0, 0.1
Dependencies base (>=4 && <5), mtl (>= && <2) [details]
License BSD-3-Clause
Author David Mazieres
Category Control
Uploaded by DavidMazieres at 2009-10-17T22:11:52Z
Reverse Dependencies 1 direct, 0 indirect [details]
Downloads 1843 total (0 in the last 30 days)
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Status Docs uploaded by user
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