microlens: A tiny lens library with no dependencies. If you're writing an app, you probably want microlens-platform, not this.

[ bsd3, data, lenses, library ] [ Propose Tags ]

NOTE: If you're writing an app, you probably want microlens-platform – it has the most features. microlens is intended more for library writers who want a tiny lens library (after all, lenses are pretty useful for everything, not just for updating records!).

This library 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.

There's a longer readme on Github. It has a migration guide for lens users, a description of other packages in the family, a discussion of other lens libraries you could use instead, and so on.

Here are some usecases for this library:

However, don't use this library if:

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

If you want to export getters or folds and don't mind the contravariant dependency, please consider using microlens-contra.

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 depends on transformers-0.2 or above.

Versions 0.1.0.0, 0.1.1.0, 0.1.2.0, 0.1.3.0, 0.1.5.0, 0.2.0.0, 0.3.0.0, 0.3.1.0, 0.3.2.0, 0.3.3.0, 0.3.4.0, 0.3.4.1, 0.3.5.0, 0.3.5.1, 0.4.0.0, 0.4.0.1, 0.4.1.0, 0.4.2.0, 0.4.2.1, 0.4.3.0, 0.4.4.0, 0.4.4.1, 0.4.4.2, 0.4.4.3, 0.4.5.0, 0.4.6.0, 0.4.7.0, 0.4.8.0, 0.4.8.1, 0.4.8.2, 0.4.8.3, 0.4.9, 0.4.9.1, 0.4.10 (info)
Change log CHANGELOG.md
Dependencies base (>=4.5 && <5), transformers (>=0.2) [details]
License BSD-3-Clause
Author Edward Kmett, Artyom Kazak
Maintainer Monadfix <hi@monadfix.io>
Category Data, Lenses
Home page http://github.com/monadfix/microlens
Bug tracker http://github.com/monadfix/microlens/issues
Source repo head: git clone git://github.com/monadfix/microlens.git
Uploaded by Artyom at Sat Nov 3 12:18:12 UTC 2018
Distributions Arch:0.4.10, Debian:0.4.9.1, Fedora:0.4.8.3, LTSHaskell:0.4.9.1, NixOS:0.4.10, Stackage:0.4.10, openSUSE:0.4.10
Downloads 29968 total (429 in the last 30 days)
Rating 2.5 (votes: 11) [estimated by rule of succession]
Your Rating
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Status Docs available [build log]
Last success reported on 2018-11-03 [all 1 reports]
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