optics-core-0.3: Optics as an abstract interface: core definitions

Safe HaskellNone
LanguageHaskell2010

Optics.IxGetter

Contents

Description

An IxGetter is an indexed version of a Getter. See the "Indexed optics" section of the overview documentation in the Optics module of the main optics package for more details on indexed optics.

Synopsis

Formation

type IxGetter i s a = Optic' A_Getter (WithIx i) s a Source #

Type synonym for an indexed getter.

Introduction

ito :: (s -> (i, a)) -> IxGetter i s a Source #

Build an indexed getter from a function.

>>> iview (ito id) ('i', 'x')
('i','x')

selfIndex :: IxGetter a a a Source #

Use a value itself as its own index. This is essentially an indexed version of equality.

Elimination

iview :: (Is k A_Getter, is `HasSingleIndex` i) => Optic' k is s a -> s -> (i, a) Source #

View the value pointed to by an indexed getter.

iviews :: (Is k A_Getter, is `HasSingleIndex` i) => Optic' k is s a -> (i -> a -> r) -> s -> r Source #

View the function of the value pointed to by an indexed getter.

Subtyping

data A_Getter :: OpticKind Source #

Tag for a getter.

Instances
ReversibleOptic A_Getter Source # 
Instance details

Defined in Optics.Re

Associated Types

type ReversedOptic A_Getter = (r :: Type) Source #

Methods

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

Is A_Getter A_Fold Source # 
Instance details

Defined in Optics.Internal.Optic.Subtyping

Methods

implies :: (Constraints A_Getter p -> r) -> Constraints A_Fold p -> r Source #

Is A_Getter An_AffineFold Source # 
Instance details

Defined in Optics.Internal.Optic.Subtyping

Is A_ReversedPrism A_Getter Source # 
Instance details

Defined in Optics.Internal.Optic.Subtyping

Is A_Lens A_Getter Source # 
Instance details

Defined in Optics.Internal.Optic.Subtyping

Methods

implies :: (Constraints A_Lens p -> r) -> Constraints A_Getter p -> r Source #

Is An_Iso A_Getter Source # 
Instance details

Defined in Optics.Internal.Optic.Subtyping

Methods

implies :: (Constraints An_Iso p -> r) -> Constraints A_Getter p -> r Source #

(s ~ t, a ~ b) => ToReadOnly A_Getter s t a b Source # 
Instance details

Defined in Optics.ReadOnly

Methods

getting :: Optic A_Getter is s t a b -> Optic' (Join A_Getter A_Getter) is s a Source #

(s ~ t, a ~ b) => IxOptic A_Getter s t a b Source # 
Instance details

Defined in Optics.Indexed.Core

Methods

noIx :: NonEmptyIndices is => Optic A_Getter is s t a b -> Optic A_Getter NoIx s t a b Source #

(Functor f, f ~ g, s ~ t, a ~ b) => MappingOptic A_Getter f g s t a b Source #
>>> [('a', True), ('b', False)] ^. _1 %& mapping
"ab"
>>> let v = [[ (('a', True), "foo"), (('b', False), "bar")], [ (('c', True), "xyz") ] ]
>>> v ^. _1 % _2 %& mapping %& mapping
[[True,False],[True]]
Instance details

Defined in Optics.Mapping

Associated Types

type MappedOptic A_Getter :: Type Source #

Methods

mapping :: AcceptsEmptyIndices "mapping" is => Optic A_Getter is s t a b -> Optic (MappedOptic A_Getter) is (f s) (g t) (f a) (g b) Source #

type ReversedOptic A_Getter Source # 
Instance details

Defined in Optics.Re

type MappedOptic A_Getter Source # 
Instance details

Defined in Optics.Mapping