lens-family

Lens Families

Version on this page:	1.2.0
LTS Haskell 11.6:	1.2.2
Stackage Nightly 2018-04-25:	1.2.2
Latest on Hackage:	1.2.2

See all snapshots lens-family appears in

BSD3 licensed by Russell O'Connor

Maintained by Russell O'Connor

Module documentation for 1.2.0

Lens
- Lens.Family2

This package provides first class functional references. In addition to the usual operations of getting, setting and composition, plus integration with monad state, lens families provide some unique features:

Polymorphic updating
Traversals
Cast projection functions to read-only lenses
Cast "toList" functions to read-only traversals
Cast semantic editor combinators to modify-only traversals.

Changes

1.2.1 (Changes from 1.2.0)
=========================
* Bump dependency on transformers and mtl

1.2.0 (Changes from 1.1.0)
=========================
* Corrected associativity of ^. ^.. and ^? from right to left.

1.1.0 (Changes from 1.0.1)
=========================
* Some type synonym definitions have been altered, but should be equivalent.
* Removed Getting and Setting functors and instead use the equivalent standard functors Const and Identity.
* Renamed Setter to ASetter and generalized Setters to be a LensLike constrained to an "Identical" functor.
* Added the (<~) operator.
* Corrected the definition of ATraversal'

1.0.1 (Changes from 1.0.0)
=========================
* Bump dependency on transformers and mtl

1.0.0 (Changes from 0.1.0)
=========================
* added support for folds and traversals
* renamed all functions to be mostly compatible with the lexicon from lens.

0.1.0 (Changes from 0.0.1)
=========================
* added project and sec
* added <>= and <>~
* renamed functional modifier operators
* moving setting to Lens.Family2.Unchecked because one needs to verify the functor laws

0.0.1 (Changes from 0.0.0)
=========================
* Bump dependency on containers
* Fixed dependency on mtl

Depends on 5 packages:

base, containers, lens-family-core, mtl, transformers