microlens support for Reader/Writer/State from mtl http://github.com/aelve/microlens

Version on this page:
LTS Haskell 15.14:
Stackage Nightly 2020-05-26:
Latest on Hackage:

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BSD-3-Clause licensed by Artyom
Maintained by Artyom

Module documentation for

This version can be pinned in stack with:[email protected]:d7506dac17575c69112256e96131242dd1ed300917a676ff000f32190289737f,1495

This package contains functions (like view or +=) which work on MonadReader, MonadWriter, and MonadState from the mtl package.

This package is a part of the microlens family; see the readme on Github.


  • Added preview (a synonym for (^?)).
  • Bumped microlens version again.

  • Bumped microlens version.

  • Moved some internally used functions to Lens.Micro.Internal in microlens.
  • Bumped base version.

  • Package now compiles with -O2 and other optimisations by default.

  • Added zoom and magnify.

Initial release.