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(GEq (Rep10 rec), Representable10 rec) + => (forall n. Getting (Ap10 a n) (rec n) (Ap10 a n)) + -> Prism' (Rep10 rec :** m) (m a) +_Field10' l = _Field10 @(Rep10 rec) (field10 l) + +infixr 5 != +-- | Shortcut to construct a (':**') from a 'Control.Lens.Getter'. +-- +-- Note that this assumes the fields are ultimately wrapped in 'Ap10'. If a +-- particular field doesn't have 'Ap10' (which can only arise from a +-- manually-written 'Representable10' instance), just pretend it does by adding +-- @from ap10@ to the lens. +(!=) + :: Representable10 rec + => (forall m. Getting (Ap10 a m) (rec m) (Ap10 a m)) + -> f a -> Rep10 rec :** f +l != x = field10 l :** x + +infixr 5 !=? +-- | Shortcut to construct a (':**') using 'pure' for the value. +(!=?) + :: (Representable10 rec, Applicative f) + => (forall m. Getting (Ap10 a m) (rec m) (Ap10 a m)) + -> a -> Rep10 rec :** f +l !=? x = l != pure x + +-- | Lifts a 'Setter' to work underneath (':**'). +-- +-- This means if you know how to change the type of a whole record, you can use +-- this to change the type of a (':**'). +-- +-- Example usage: +-- +-- data MyRecord a m = MyRecord { _mrA :: Ap10 a m, _mrInt :: Ap10 Int m } +-- mrA :: Lens' (MyRecord a m) (MyRecord b m) (Ap10 m a) (Ap10 m b) +-- +-- example +-- :: Rep10 (MyRecord Int) :** Identity +-- -> Rep10 (MyRecord String) :** Identity +-- example = fragmented (mrA.ap10) %~ show +fragmented + :: ( Functor m, Representable10 recA, Representable10 recB + , f ~ OpCostar m (Rep10 recB :** m) + ) + => ASetter (recB f) (recA f) (f b) (f a) + -> Setter (Rep10 recA :** m) (Rep10 recB :** m) a b +fragmented l = setting $ \f -> lmapFragment (l %~ contramap f) diff --git a/ten-lens.cabal b/ten-lens.cabal new file mode 100644 --- /dev/null +++ b/ten-lens.cabal @@ -0,0 +1,44 @@ +cabal-version: 1.12 + +-- This file has been generated from package.yaml by hpack version 0.33.0. +-- +-- see: https://github.com/sol/hpack +-- +-- hash: e2344930ad9083c232a788c6d18fb775971206770c51ed1d1bd15038c40740e8 + +name: ten-lens +version: 0.1.0.0 +synopsis: Lenses for the types in the "ten" package. +description: This provides lenses and related functionality for "ten". It's in a separate + package to reduce the dependency weight of "ten" itself. +category: Data +homepage: https://github.com/google/hs-ten#readme +bug-reports: https://github.com/google/hs-ten/issues +author: Andrew Pritchard +maintainer: Andrew Pritchard +copyright: 2018-2021 Google LLC +license: Apache-2.0 +license-file: LICENSE +build-type: Simple +extra-source-files: + CHANGELOG.md + +source-repository head + type: git + location: https://github.com/google/hs-ten + subdir: ten-lens + +library + exposed-modules: + Data.Ten.Lens + other-modules: + Paths_ten_lens + hs-source-dirs: + src + build-depends: + base >=4.12 && <4.16 + , lens >=1.5 && <5.1 + , profunctors >=0.1 && <5.7 + , some >=1.0 && <1.1 + , ten >=0.1 && <0.2 + default-language: Haskell2010