The monad-journal package

[Tags: bsd3, library]

This package provides a typeclass for logging in pure code, or more generally, in any kind of context. You can do whatever you want with logs, especially get them, clear them or even sink them through IO if you're logging in (MonadIO m) => m.

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Versions0.1.0.0,,,,,,,,, 0.2.4, 0.3, 0.4,,, 0.5,, 0.6,,, 0.7, 0.7.1
Dependenciesbase (>=4.5 && <5.0), either (>=4.1 && <4.5), monad-control (>=0.3 && <1.1), mtl (>=2.1 && <2.3), transformers (>=0.3 && <0.5), transformers-base (==0.4.*) [details]
AuthorDimitri Sabadie <>
MaintainerDimitri Sabadie <>
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Source repositoryhead: git clone git://
UploadedFri May 29 17:21:55 UTC 2015 by DimitriSabadie
DistributionsArch:0.7.1, Debian:0.7.1, LTSHaskell:0.7.1, NixOS:0.7.1, Stackage:0.7.1
Downloads17533 total (47 in last 30 days)
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StatusDocs uploaded by user
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Maintainers' corner

For package maintainers and hackage trustees

Readme for monad-journal-0.7.1


Pure logger typeclass and monad transformer

What is monad-journal?

monad-journal is a simple but powerful answer to the logging problem. A lot of people think that “logging” is IO-related, while it’s not. Everyone must know MonadWriter , which is perfect to log things in pure computations. The issue is that you can’t access those “things” inside the computation itself. monad-journal exposes a cool typeclass called MonadJournal that enables you to do so.