microlens

A tiny part of the lens library which you can depend upon

http://github.com/aelve/microlens

Version on this page:0.3.3.0
LTS Haskell 18.23:0.4.12.0
Stackage Nightly 2022-01-24:0.4.12.0
Latest on Hackage:0.4.12.0

See all snapshots microlens appears in

BSD-3-Clause licensed by Artyom
Maintained by Artyom
This version can be pinned in stack with:microlens-0.3.3.0@sha256:a22b2604f1014474abbb2e3fc6988b14f58c3b5e61d69ea3a2fe775b8b6a24e3,3107

Module documentation for 0.3.3.0

Depends on 1 package(full list with versions):
Used by 3 packages in nightly-2015-08-26(full list with versions):

This is an extract from lens (with no dependencies). It's not a toy lenses library, unsuitable for “real world”, but merely a small one. It is compatible with lens, and should have same performance. It also has better documentation.

Use this library:

  • if you want to define lenses or traversals in your own library, but don't want to depend on lens

  • if you are new to lenses and want a small library to play with, but don't want to use something “inferior” or have to relearn things when/if you switch to lens

Don't use this library:

  • if you need Isos, Prisms, indexed traversals, or actually anything else which isn't defined here

  • if you want a library with a clean, understandable implementation (in which case you're looking for lens-simple)

If you're writing an application which uses lenses more extensively, look at microlens-platform – it combines features of all other microlens packages (microlens-mtl, microlens-th, microlens-ghc).

There's a longer readme on Github, you should read it if you're still interested about using this library.

If you haven't ever used lenses before, read this tutorial. (It's for lens, but it applies to microlens just as well.)

Note that microlens has no dependencies starting from GHC 7.10 (base-4.8). Prior to that, it has to depend on transformers-0.2 or above.

Changes

0.3.3.0

  • Added filtered.
  • Added Safe Haskell pragmas.

0.3.2.0

  • Added toListOf back.
  • Added to.

0.3.1.0

  • Added LensLike and LensLike'.
  • Added failing.

0.3.0.0

  • Moved Lens.Micro.Classes into Lens.Micro.Internal.
  • Added <%~, <<%~, <<.~.

0.2.0.0

  • Removed toListOf.
  • Removed +~, -~, *~, //~ and the Lens.Micro.Extras module.

0.1.5.0

  • Added ix and at.
  • Added traversed.
  • Moved some things into Lens.Micro.Internal.
  • Bumped base version.

0.1.3.0

  • Moved some things into Lens.Micro.Type and Lens.Micro.Classes.
  • Each and Field* aren’t exported by Lens.Micro now.

0.1.2.0

  • Added each.

0.1.1.0

  • Added ASetter', which is useful because we can’t provide real Setter and Setter'.

0.1.0.0

First release.