Control.Effect.Internal.Membership

Documentation

data ElemOf (e :: a) (r :: [a]) where

Constructors

Here :: ElemOf e (e ': r)

There :: ElemOf e r -> ElemOf e (_e ': r)

Instances

Show (ElemOf e r)

Defined in Control.Effect.Internal.Membership

Methods

showsPrec :: Int -> ElemOf e r -> ShowS

show :: ElemOf e r -> String

showList :: [ElemOf e r] -> ShowS

absurdMember :: ElemOf e '[] -> b

sameMember :: forall e e' r. ElemOf e r -> ElemOf e' r -> Maybe (e :~: e')

class Member e r where

A constraint that e is part of the effect row r.

r is typically Derivs m for some m. Member e (Derivs m) allows you to use actions of e with m.

If e occurs multiple times in r, then the first occurence will be used.

If possible, use Eff/s instead.

Methods

membership :: ElemOf e r

Instances

(TypeError ((('Text "Unhandled effect: " :<>: 'ShowType e) :$$: 'Text "You need to either add or replace an interpreter in your interpretation stack so that the effect gets handled.") :$$: 'Text "To check what effects are currently handled by your interpretation stack, use `debugEffects' from `Control.Effect.Debug'.") :: Constraint) => Member (e :: k) ('[] :: [k])

Defined in Control.Effect.Internal.Membership

Methods

membership :: ElemOf e '[]

Member e r => Member (e :: a) (_e ': r :: [a])

Defined in Control.Effect.Internal.Membership

Methods

membership :: ElemOf e (_e ': r)

Member (e :: a) (e ': r :: [a])

Defined in Control.Effect.Internal.Membership

Methods

membership :: ElemOf e (e ': r)