Optics.Review

A Review is a backwards Getter, i.e. a Review T B is just a function B -> T.

Formation

type Review t b = Optic' A_Review NoIx t b

Type synonym for a review.

Introduction

unto :: (b -> t) -> Review t b

An analogue of to for reviews.

Elimination

review :: Is k A_Review => Optic' k is t b -> b -> t

Retrieve the value targeted by a Review.

>>> review _Left "hi"
Left "hi"

Computation

review (unto f) = f

Subtyping

data A_Review :: OpticKind

Tag for a review.

Instances

ReversibleOptic A_Review

Defined in Optics.Re

Associated Types

type ReversedOptic A_Review = (r :: Type)

Methods

re :: AcceptsEmptyIndices "re" is => Optic A_Review is s t a b -> Optic (ReversedOptic A_Review) is b a t s

Is A_ReversedLens A_Review

Defined in Optics.Internal.Optic.Subtyping

Methods

implies :: proxy A_ReversedLens A_Review p -> (Constraints A_ReversedLens p -> r) -> Constraints A_Review p -> r

Is A_Prism A_Review

Defined in Optics.Internal.Optic.Subtyping

Methods

implies :: proxy A_Prism A_Review p -> (Constraints A_Prism p -> r) -> Constraints A_Review p -> r

Is An_Iso A_Review

Defined in Optics.Internal.Optic.Subtyping

Methods

implies :: proxy An_Iso A_Review p -> (Constraints An_Iso p -> r) -> Constraints A_Review p -> r

type ReversedOptic A_Review

Defined in Optics.Re

type ReversedOptic A_Review = A_Getter