The monad-control package

[Tags: bsd3, library]

This package defines the type class MonadBaseControl, a subset of MonadBase into which generic control operations such as catch can be lifted from IO or any other base monad. Instances are based on monad transformers in MonadTransControl, which includes all standard monad transformers in the transformers library except ContT.

See the lifted-base package which uses monad-control to lift IO operations from the base library (like catch or bracket) into any monad that is an instance of MonadBase or MonadBaseControl.

Note that this package is a rewrite of Anders Kaseorg's monad-peel library. The main difference is that this package provides CPS style operators and exploits the RankNTypes and TypeFamilies language extensions to simplify and speedup most definitions.

The following criterion based benchmark shows that monad-control is on average about 99% faster than monad-peel:

git clone


Versions0.1, 0.2,,,, 0.3,, 0.3.1,,,,, 0.3.2,,,,
Dependenciesbase (>=3 && <5), base-unicode-symbols (>=0.1.1 && <0.3), transformers (>=0.2 && <0.4), transformers-base (>=0.4.1 && <0.5)
Copyright(c) 2011 Bas van Dijk, Anders Kaseorg
AuthorBas van Dijk, Anders Kaseorg
MaintainerBas van Dijk <>
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Source repositoryhead: git clone git://
Upload dateTue Apr 23 16:41:01 UTC 2013
Uploaded byBasVanDijk
DistributionsDebian:, Fedora:, FreeBSD:, NixOS:
Downloads111678 total (13492 in last 30 days)




instancestIf enabled this package will export MonadBaseControl instances for the lazy and strict ST monad. If disabled these instances are only exported when base >= 4.4. If enabled it is required that the transformer-base package exports MonadBase instances for ST. It will do this by default.Enabled

Use -f <flag> to enable a flag, or -f -<flag> to disable that flag. More info


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