generic-deepseq: Generic deep evaluation of data structures

[ bsd3, control, generics, library ] [ Propose Tags ]

This package provides a deepseq function analogous to seq, except that it traverses the entire data structure, evaluating it fully, and not just up to head normal form.

Using lists as an example:

> [1,2,undefined] `seq` 3

Whereas with deepseq:

> [1,2,undefined] `deepseq` 3
*** Exception: Prelude.undefined

Unlike the deepseq package, this implementation is based on the GHC.Generics framework as found in GHC >= 7.2, so that it can generate instances automatically for any datatype that has a Generic instance, without further code.

data MyType = MyType String Int (Maybe Double)
  deriving Generic
instance DeepSeq MyType

Changes in version

  • Vastly improved performance. As a consequence of these changes, the member function of the DeepSeq class is now rnf, instead of deepseq.

  • New instances for functions, Ratio and Complex types.

Changes in version

  • Fix the U1 and V1 instances.

Changes in version

  • No functional changes, updated to correct the URLs of the repository and the issue tracker.




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],,,
Dependencies base (>=4.4 && <5), ghc-prim (>=0.2) [details]
License BSD-3-Clause
Copyright 2012, Maxime Henrion
Author Maxime Henrion
Maintainer Maxime Henrion <>
Revised Revision 1 made by AdamBergmark at 2015-05-09T12:17:48Z
Category Control, Generics
Bug tracker
Source repo head: hg clone
Uploaded by MaximeHenrion at 2012-02-28T20:53:40Z
Distributions NixOS:
Reverse Dependencies 1 direct, 0 indirect [details]
Downloads 3810 total (16 in the last 30 days)
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