Control.Lens.Internal.Action

Actions

class (Monad m, Functor f, Contravariant f) => Effective m r f | f -> m r where

An Effective Functor ignores its argument and is isomorphic to a Monad wrapped around a value.

That said, the Monad is possibly rather unrelated to any Applicative structure.

Methods

effective :: m r -> f a

ineffective :: f a -> m r

Instances

Effective Identity r (Accessor r)

Monad m => Effective m r (Effect m r)

Effective m r f => Effective m (Dual r) (Backwards f)

newtype Effect m r a

Wrap a monadic effect with a phantom type argument.

Constructors

Effect

Fields

getEffect :: m r

Instances

Monad m => Effective m r (Effect m r)

Functor (Effect m r)

(Monad m, Monoid r) => Applicative (Effect m r)

Contravariant (Effect m r)

(Apply m, Semigroup r) => Apply (Effect m r)

(Monad m, Monoid r) => Monoid (Effect m r a)

(Apply m, Semigroup r) => Semigroup (Effect m r a)