Optics as an abstract interface: core definitions

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Stackage Nightly 2024-07-13:
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BSD-3-Clause licensed by Adam Gundry, Andres Löh, Andrzej Rybczak, Oleg Grenrus
Maintained by [email protected]
This version can be pinned in stack with:optics-core-,5555

Module documentation for

This package makes it possible to define and use Lenses, Traversals, Prisms and other optics, using an abstract interface.

This variant provides core definitions with a minimal dependency footprint. See the optics package (and its dependencies) for documentation and the "batteries-included" variant.


optics-core- (2023-06-22)

  • Add INLINE pragmas to small functions that really should inline

optics-core-0.4.1 (2022-03-22)

  • Add support for GHC-9.2
  • Add is (#410)
  • Improve error messages related to the JoinKinds class (#439)
  • Port universeOf, cosmosOf, paraOf, rewriteOf, transformOf, rewriteMOf and transformMOf from Control.Lens.Plated (#379)
  • Add (%?) composition operator (#434)

optics-core-0.4 (2021-02-22)

  • See migration-guide-0.4.md for more details
  • Add support for GHC-9.0
  • Drop support for GHC-8.0
  • The FunctorWithIndex, FoldableWithIndex and TraversableWithIndex type classes have been migrated to a new package, indexed-traversable (#370)
  • Add adjoin, iadjoin and both to Optics.[Ix]Traversal (#332, #372)
  • Add ifst and isnd to Optics.IxLens (#389)
  • Generalize types of generic (#376)
  • Make chosen an indexed lens to see which value is traversed (#335)
  • Remove GeneralLabelOptic extensibility mechanism (#361)
  • Add gfield, gafield, gconstructor, gposition and gplate for generics-based data access (#358, #361)
  • Add support for generics-based field lenses and constructor prisms (gfield and gconstructor) to LabelOptic so they can be used via OverloadedLabels (#361)
  • Remove unnecessary INLINE pragmas to reduce compile times (#394)
  • Simplify the type of (%) using new JoinKinds and AppendIndices classes in place of the Join and Append type families (#397, #399)

optics-core- (2020-08-05)

  • Add INLINE pragmas to atraverseOf_, iaTraverseOf_ and ignored
  • Improve error message in catch-all GeneralLabelOptic instance
  • Make GHC optimize away profunctor type classes when profiling is enabled
  • Improve documentation of Optics.Label:
    • Add guide on how to effectively use labels as optics
    • Restructure existing sections

optics-core-0.3 (2020-04-15)

  • GHC-8.10 support
  • Add filteredBy and unsafeFilteredBy
  • Add FunctorWithIndex, FoldableWithIndex and TraversableWithIndex instances for Const and Constant
  • Add afoldVL and iafoldVL constructors
  • Rename toAtraversalVL to atraverseOf, and toIxAtraversalVL to iatraverseOf
  • Generalise element and elementOf to construct IxAffineTraversals instead of IxTraversals
  • Change mapping to work on optic kinds other than Iso: it now supports Lens and Prism degenerating to Getter and Review respectively
  • Generalise ignored to be an IxAffineTraversal instead of an IxTraversal
  • Add singular and isingular
  • Add (^?!) operator
  • Expose Curry and CurryCompose
  • Show expected elimination forms on optic kind mismatch
  • Use stricter uncurry' for better performance
  • Add hidden LabelOptic instance to postpone instance resolution
  • Add GeneralLabelOptic for pluggable generic optics as labels
  • Document monoidal structures of Folds
  • Remove proxy argument from implies
  • Add itoList

optics-core-0.2 (2019-10-18)

  • Add non, non' and anon to Optics.Iso
  • ix can produce optic kinds other than AffineTraversal
  • Generalise type of generic1
  • Move some internal definitions out to new indexed-profunctors package
  • Introduce OpticKind and IxList type synonyms for better type inference
  • Make itraverse for Seq faster for containers >= 0.6.0
  • Assorted documentation improvements

optics-core-0.1 (2019-09-02)

  • Initial release