Data.OpenUnion.Internal

Documentation

data Union as where

Constructors

Single :: a -> Union (a : as)

Union :: Union as -> Union (a : as)

Exhausted :: Union [] -> Union []

Instances

All Show r => Show (Union r)

exhaust :: Union [] -> a

type family All ca as :: Constraint

Instances

type All ca ([] *) = ()

type All ca ((:) * a as) = (ca a, All ca as)

(||>) :: (a -> r) -> (Union as -> r) -> Union (a : as) -> r infixr 2

data Position a as where

Constructors

Zero :: Position a (a : as)

Succ :: Position a as -> Position a (b : as)

class Member a as | as -> a where

Methods

position :: Position a as

Instances

Member a as => Member a ((:) * b as)

Member a ((:) * a as)

liftU :: forall a as. Member a as => a -> Union as

Lift a value into a Union.

picked :: forall a as f. (Applicative f, Member a as) => (a -> f a) -> Union as -> f (Union as)

Traversal for a specific element.

retractU :: Member a as => Union as -> Maybe a

Retrieve the value from a Union.

hoistU :: Member a as => (a -> a) -> Union as -> Union as

Lift a function into Union.

newtype Id a

Instead of Identity.

Constructors

Id

Fields

getId :: a

Instances

Functor Id

Applicative Id

class Include as bs where

Methods

reunion :: Union as -> Union bs

Instances

Include ([] *) bs

(Member a bs, Include as bs) => Include ((:) * a as) bs

type (∈) a as = Member a as infix 4

type (⊆) as bs = Include as bs infix 4

type (＝) as bs = (Include as bs, Include bs as) infix 4