dejafu: Overloadable primitives for testable, potentially non-deterministic, concurrency.

[ concurrency, library, mit ] [ Propose Tags ]

[Déjà Fu is] A martial art in which the user's limbs move in time as well as space, […] It is best described as "the feeling that you have been kicked in the head this way before" -- Terry Pratchett, Thief of Time

Concurrency is nice, deadlocks and race conditions not so much. The Par monad family, as defined in abstract-par provides deterministic parallelism, but sometimes we can tolerate a bit of nondeterminism.

This package provides a class of monads for potentially nondeterministic concurrency, with an interface in the spirit of GHC's normal concurrency abstraction.

MonadConc with IO:

The intention of the MonadConc class is to provide concurrency where any apparent nondeterminism arises purely from the scheduling behaviour. To put it another way, a given computation, parametrised with a fixed set of scheduling decisions, is deterministic. This assumption is used by the testing functionality provided by Test.DejaFu.

Whilst this assumption may not hold in general when IO is involved, you should strive to produce test cases where it does.

See the README for more details.


Note: This package has metadata revisions in the cabal description newer than included in the tarball. To unpack the package including the revisions, use 'cabal get'.

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Versions [RSS],,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, (info)
Dependencies base (>=4.5 && <4.9), containers (>=0.5 && <0.6), deepseq (>=1.1 && <1.5), exceptions (>=0.7 && <0.9), monad-loops (<0.5), mtl (<2.3), random (<1.2), stm (<2.5), transformers (<0.6) [details]
License MIT
Author Michael Walker
Revised Revision 1 made by HerbertValerioRiedel at 2016-11-29T22:07:00Z
Category Concurrency
Home page
Source repo head: git clone
this: git clone
Uploaded by barrucadu at 2015-08-27T12:37:43Z
Distributions LTSHaskell:, NixOS:, Stackage:
Reverse Dependencies 7 direct, 26 indirect [details]
Downloads 44510 total (96 in the last 30 days)
Rating 2.0 (votes: 1) [estimated by Bayesian average]
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Status Docs available [build log]
Last success reported on 2015-08-27 [all 1 reports]