transformers-compat: A small compatibility shim exposing the new types from transformers 0.3 to older Haskell platforms.

[ bsd3, compatibility, library ] [ Propose Tags ]
Versions 0.1, 0.1.1,, 0.2, 0.3, 0.3.2, 0.3.3,,,,,,,,,,,,,,,,,
Change log CHANGELOG.markdown
Dependencies base (>=4.3 && <5), transformers (>=0.2 && <0.4) [details]
License BSD-3-Clause
Copyright Copyright (C) 2012 Edward A. Kmett
Author Edward A. Kmett
Maintainer Edward A. Kmett <>
Category Compatibility
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Source repo head: git clone git://
Uploaded by EdwardKmett at Wed Mar 20 20:04:30 UTC 2013
Distributions Arch:, Debian:, Fedora:, FreeBSD:, LTSHaskell:, NixOS:, Stackage:, openSUSE:
Downloads 303685 total (838 in the last 30 days)
Rating 2.0 (votes: 1) [estimated by rule of succession]
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Status Docs uploaded by user
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This package includes backported versions of types that were added to transformers in transformers 0.3 for users who need strict transformers 0.2 compatibility to run on old versions of the platform, but also need those types.

Those users should be able to just depend on transformers >= 0.2 and transformers-compat.

Note: missing methods are not supplied but this at least permits the types to be used.

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  • Control
    • Applicative
      • Control.Applicative.Backwards
      • Control.Applicative.Lift
  • Data
    • Functor
      • Data.Functor.Reverse




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Maintainer's Corner

For package maintainers and hackage trustees

Readme for transformers-compat-

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Build Status

This provides a thin compatibility shim on top of transformers-0.2 to add the types that were added in transformers-0.3.

This enables users to maintain haskell-platform compatibility, while still gaining access ot the new functionality.

Contact Information

Contributions and bug reports are welcome!

Please feel free to contact me through github or on the #haskell IRC channel on

-Edward Kmett