lens-4.8: Lenses, Folds and Traversals

Control.Lens.Internal.Getter

Description

Synopsis

# Documentation

coerce :: (Contravariant f, Functor f) => f a -> f b Source

A Functor you can coerce ignores its argument, which it carries solely as a phantom type parameter.

By the Functor and Contravariant laws, an instance of both will necessarily satisfy:

id = fmap f = coerce = contramap g

noEffect :: (Contravariant f, Applicative f) => f a Source

The mempty equivalent for a Contravariant Applicative Functor.

newtype AlongsideLeft f b a Source

Constructors

 AlongsideLeft FieldsgetAlongsideLeft :: f (a, b)

Instances

 Traversable f => Bitraversable (AlongsideLeft f) Functor f => Bifunctor (AlongsideLeft f) Foldable f => Bifoldable (AlongsideLeft f) Functor f => Functor (AlongsideLeft f b) Foldable f => Foldable (AlongsideLeft f b) Traversable f => Traversable (AlongsideLeft f b) Contravariant f => Contravariant (AlongsideLeft f b) Traversable1 f => Traversable1 (AlongsideLeft f b) Foldable1 f => Foldable1 (AlongsideLeft f b) Read (f (a, b)) => Read (AlongsideLeft f b a) Show (f (a, b)) => Show (AlongsideLeft f b a)

newtype AlongsideRight f a b Source

Constructors

 AlongsideRight FieldsgetAlongsideRight :: f (a, b)

Instances

 Traversable f => Bitraversable (AlongsideRight f) Functor f => Bifunctor (AlongsideRight f) Foldable f => Bifoldable (AlongsideRight f) Functor f => Functor (AlongsideRight f a) Foldable f => Foldable (AlongsideRight f a) Traversable f => Traversable (AlongsideRight f a) Contravariant f => Contravariant (AlongsideRight f a) Traversable1 f => Traversable1 (AlongsideRight f a) Foldable1 f => Foldable1 (AlongsideRight f a) Read (f (a, b)) => Read (AlongsideRight f a b) Show (f (a, b)) => Show (AlongsideRight f a b)