lens-family-core

Haskell 2022 Lens Families

Version on this page:2.1.2
LTS Haskell 24.17:2.1.3
Stackage Nightly 2025-11-01:2.1.3
Latest on Hackage:2.1.3

See all snapshots lens-family-core appears in

BSD-3-Clause licensed by Russell O'Connor
Maintained by Russell O'Connor
This version can be pinned in stack with:lens-family-core-2.1.2@sha256:702013af981089f991c93598762b8804314266c2bd7d92fc35fb6a8b62af1883,2325

Module documentation for 2.1.2

Used by 3 packages in lts-19.32(full list with versions):
dhall, dhall-json, lens-family

This package provides first class(†) functional references in Van Laarhoven style supporting the following optics:

  • Lenses (view, over)

  • Traversals (toListOf, matching, over)

  • Setters (over)

  • Grates (zipWithOf, under, review)

  • Resetters (under)

  • Adapters (view, review)

  • Grids (toListOf, over / under, review)

  • Prisms (matching, over / under, review)

  • Getters (view)

  • Folders (toListOf)

  • Reviewers (review)

(†) For optimal first-class support use the lens-family package with rank 2 / rank N polymorphism. Lens.Family.Clone allows for first-class support of lenses and traversals for those who cannot support rank 2 polymorphism.