union 0.1.3 → 0.1.3.2

raw patch · 2 files changed

+16/−2 lines, 2 filesdep ~base

Dependency ranges changed: base

Files

• src/Data/Union.hs +13/−0
• union.cabal +3/−2

@@ -66,28 +66,35 @@ absurdUnion :: Union f [] -> a absurdUnion = \case{} +-- | Map over the interpretation of a union. umap :: (forall a . f a -> g a) -> Union f as -> Union g as umap f = \case   This a -> This (f a)   That u -> That (umap f u) +-- | A prism for the head label of a union. _This :: Prism (Union f (a : as)) (Union f (b : as)) (f a) (f b) _This = prism This (union (Left . That) Right) {-# INLINE _This #-} +-- | A prism for the tail of labels of a union. _That :: Prism (Union f (a : as)) (Union f (a : bs)) (Union f as) (Union f bs) _That = prism That (union Right (Left . This)) {-# INLINE _That #-} +-- | Membership of a label @a@ in a union with labels @as@. class i ~ RIndex a as => UElem (a :: u) (as :: List u) (i :: Nat) where   {-# MINIMAL uprism | ulift, umatch #-} +  -- | A prism for a value at label @a@ in the union.   uprism :: Prism' (Union f as) (f a)   uprism = prism' ulift umatch +  -- | Inject a value at label @a@ into the union.   ulift :: f a -> Union f as   ulift = review uprism +  -- | Match a value at label @a@ from the union.   umatch :: Union f as -> Maybe (f a)   umatch = preview uprism @@ -103,15 +110,19 @@     uprism = _That . uprism     {-# INLINE uprism #-} +-- | Subset relation between two lists of union labels. class is ~ RImage as bs => USubset (as :: List u) (bs :: List u) is where   {-# MINIMAL usubset | urelax, urestrict #-} +  -- | A prism for a sub-union within a larger union.   usubset :: Prism' (Union f bs) (Union f as)   usubset = prism' urelax urestrict +  -- | Widen a union to a larger set of labels.   urelax :: Union f as -> Union f bs   urelax = review usubset +  -- | Narrow a union to a smaller set of labels, failing if the actual label is not in the target set @as@.   urestrict :: Union f bs -> Maybe (Union f as)   urestrict = preview usubset @@ -126,8 +137,10 @@   urelax = union urelax ulift   urestrict ubs = This <$> umatch ubs <|> That <$> urestrict ubs +-- | A union with the trivial interpretation 'Identity', where each label @a@ carries a value of type @a@. type OpenUnion = Union Identity +-- | A prism for a value of type @a@ in an 'OpenUnion'. openUnion :: forall a as . UElem a as (RIndex a as) => Prism' (OpenUnion as) a openUnion = uprism . iso runIdentity Identity {-# INLINE openUnion #-}

@@ -1,6 +1,6 @@ cabal-version:       2.2 name:                union-version:             0.1.3+version:             0.1.3.2 synopsis:            Extensible type-safe unions description: @@ -18,6 +18,7 @@ bug-reports:         https://github.com/int-index/union/issues category:            Data build-type:          Simple+tested-with:         GHC ==9.10.3, GHC ==9.12.4, GHC ==9.14.1  source-repository head   type:                git@@ -26,7 +27,7 @@ library   exposed-modules:     Data.Union   other-modules:       Data.Union.Prism-  build-depends:       base >=4.20 && <4.22+  build-depends:       base >=4.20 && <4.23                ,       vinyl >= 0.14.3 && <0.15                ,       profunctors >=5.1 && <5.7                ,       tagged >=0.8 && <0.9