transformers-compat

A small compatibility shim exposing the new types from transformers 0.3 and 0.4 to older Haskell platforms.

http://github.com/ekmett/transformers-compat/

Version on this page:0.5.1.4
LTS Haskell 23.19:0.7.2
Stackage Nightly 2025-04-24:0.7.2
Latest on Hackage:0.7.2

See all snapshots transformers-compat appears in

BSD-3-Clause licensed by Edward A. Kmett
Maintained by Edward A. Kmett
This version can be pinned in stack with:transformers-compat-0.5.1.4@sha256:1b4bfa8589afb1ca0e719129ab261bd90ef0cc3e6c0b9963f94970c082b61250,2805

Module documentation for 0.5.1.4

transformers-compat

Hackage 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 irc.freenode.net.

-Edward Kmett

Changes

0.4.0.4

0.4.0.3

0.4.0.2

  • Each of these is a build with a different set of flags configured. Building this way allows us to work around bugs in cabal’s backtracker.

0.4

  • Added support for the missing ExceptT instances from mtl.

    This was not done lightly. While this means that by default incurring a dependency on transformers-compat drags in mtl when you are using an old transformers, it means that users do not have to orphan these instances and permits wider adoption of ExceptT.

    If you absolutely can’t stand mtl and really want this package to build as valid Haskell98, then you can use cabal install transformers-compat -f-mtl to avoid incurring the dependency to get these instances. However, that is effectively an unsupported configuration.

0.3.3.4

0.3.3.3

0.3.3.2

  • These releases were a successful attempt to fix build problems caused by the cabal backtracker.
  • Each of these is a build with a different set of flags configured.

0.3.2

  • This release was a failed (or at least, only partially successful) attempt to fix build problems caused by the cabal backtracker.

0.3.1

  • transformers 0.4.1 compatibility

0.3

  • Added the instances for Data.Functor.Classes from transformers 0.4
  • Switched Control.Applicative.Backwards and Data.Functor.Reverse to the split constructor/accessor style from transformers 0.4.

0.2

  • Added the new types and classes from transformers 0.4

0.1.1.1

  • Wrote a better synopsis

0.1.1

  • Updated to trick cabal into building an empty libHStransformers-compat-0.1.a on GHC 7.6.

0.1

  • Repository initialized by pulling the transformers-0.2 compatibility layer out of lens.