PLens (core 4.7 API)

java.lang.Object
- fj.data.optic.PLens<S,T,A,B>

Type Parameters:

S - the source of a PLens

T - the modified source of a PLens

A - the target of a PLens

B - the modified target of a PLens

Direct Known Subclasses:

Lens
```
public abstract class PLens<S,T,A,B>
extends java.lang.Object
```
A PLens can be seen as a pair of functions: - `get: S => A` i.e. from an `S`, we can extract an `A` - `set: (B, S) => T` i.e. if we replace an `A` by a `B` in an `S`, we obtain a `T` A PLens could also be defined as a weaker PIso where set requires an additional parameter than reverseGet. PLens stands for Polymorphic Lens as it set and modify methods change a type `A` to `B` and `S` to `T`. Lens is a PLens restricted to monomoprhic updates. A PLens is also a valid Getter, Fold, POptional, PTraversal and PSetter Typically a PLens or Lens can be defined between a Product (e.g. case class, tuple, HList) and one of it is component.

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`Fold<S,A>`	`asFold()` view a `PLens` as a `Fold`
`Getter<S,A>`	`asGetter()` view a `PLens` as a `Getter`
`POptional<S,T,A,B>`	`asOptional()` view a `PLens` as an `POptional`
`PSetter<S,T,A,B>`	`asSetter()` view a `PLens` as a `PSetter`
`PTraversal<S,T,A,B>`	`asTraversal()` view a `PLens` as a `PTraversal`
`<C> Fold<S,C>`	`composeFold(Fold<A,C> other)` compose a `PLens` with a `Fold`
`<C> Getter<S,C>`	`composeGetter(Getter<A,C> other)` compose a `PLens` with a `Getter`
`<C,D> PLens<S,T,C,D>`	`composeIso(PIso<A,B,C,D> other)` compose a `PLens` with an `PIso`
`<C,D> PLens<S,T,C,D>`	`composeLens(PLens<A,B,C,D> other)` compose a `PLens` with a `PLens`
`<C,D> POptional<S,T,C,D>`	`composeOptional(POptional<A,B,C,D> other)` compose a `PLens` with an `POptional`
`<C,D> POptional<S,T,C,D>`	`composePrism(PPrism<A,B,C,D> other)` compose a `PLens` with a `PPrism`
`<C,D> PSetter<S,T,C,D>`	`composeSetter(PSetter<A,B,C,D> other)` compose a `PLens` with a `PSetter`
`<C,D> PTraversal<S,T,C,D>`	`composeTraversal(PTraversal<A,B,C,D> other)` compose a `PLens` with a `PTraversal`
`abstract A`	`get(S s)` get the target of a `PLens`
`abstract F<S,T>`	`modify(F<A,B> f)` modify polymorphically the target of a `PLens` using a function
`abstract <L> F<S,Either<L,T>>`	`modifyEitherF(F<A,Either<L,B>> f)` modify polymorphically the target of a `PLens` with an Applicative function
`abstract <C> F<S,F<C,T>>`	`modifyFunctionF(F<A,F<C,B>> f)` modify polymorphically the target of a `PLens` with an Applicative function
`abstract F<S,IO<T>>`	`modifyIOF(F<A,IO<B>> f)` modify polymorphically the target of a `PLens` with an Applicative function
`abstract F<S,List<T>>`	`modifyListF(F<A,List<B>> f)` modify polymorphically the target of a `PLens` with an Applicative function
`abstract F<S,Option<T>>`	`modifyOptionF(F<A,Option<B>> f)` modify polymorphically the target of a `PLens` with an Applicative function
`abstract F<S,P1<T>>`	`modifyP1F(F<A,P1<B>> f)` modify polymorphically the target of a `PLens` with an Applicative function
`abstract F<S,Promise<T>>`	`modifyPromiseF(F<A,Promise<B>> f)` modify polymorphically the target of a `PLens` with an Applicative function
`abstract F<S,Stream<T>>`	`modifyStreamF(F<A,Stream<B>> f)` modify polymorphically the target of a `PLens` with an Applicative function
`abstract F<S,Trampoline<T>>`	`modifyTrampolineF(F<A,Trampoline<B>> f)` modify polymorphically the target of a `PLens` with an Applicative function
`abstract F<S,V2<T>>`	`modifyV2F(F<A,V2<B>> f)` modify polymorphically the target of a `PLens` with an Applicative function
`abstract <E> F<S,Validation<E,T>>`	`modifyValidationF(F<A,Validation<E,B>> f)` modify polymorphically the target of a `PLens` with an Applicative function
`static <S,T> PLens<S,T,S,T>`	`pId()`
`static <S,T,A,B> PLens<S,T,A,B>`	`pLens(F<S,A> get, F<B,F<S,T>> set)` create a `PLens` using a pair of functions: one to get the target, one to set the target.
`abstract F<S,T>`	`set(B b)` set polymorphically the target of a `PLens` using a function
`<S1,T1> PLens<Either<S,S1>,Either<T,T1>,A,B>`	`sum(PLens<S1,T1,A,B> other)` join two `PLens` with the same target

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

get
```
public abstract A get(S s)
```
get the target of a PLens

set
```
public abstract F<S,T> set(B b)
```
set polymorphically the target of a PLens using a function

modifyFunctionF
```
public abstract <C> F<S,F<C,T>> modifyFunctionF(F<A,F<C,B>> f)
```
modify polymorphically the target of a PLens with an Applicative function

modifyEitherF
```
public abstract <L> F<S,Either<L,T>> modifyEitherF(F<A,Either<L,B>> f)
```
modify polymorphically the target of a PLens with an Applicative function

modifyIOF
```
public abstract F<S,IO<T>> modifyIOF(F<A,IO> f)
```
modify polymorphically the target of a PLens with an Applicative function

modifyTrampolineF
```
public abstract F<S,Trampoline<T>> modifyTrampolineF(F<A,Trampoline> f)
```
modify polymorphically the target of a PLens with an Applicative function

modifyPromiseF
```
public abstract F<S,Promise<T>> modifyPromiseF(F<A,Promise> f)
```
modify polymorphically the target of a PLens with an Applicative function

modifyListF
```
public abstract F<S,List<T>> modifyListF(F<A,List> f)
```
modify polymorphically the target of a PLens with an Applicative function

modifyOptionF
```
public abstract F<S,Option<T>> modifyOptionF(F<A,Option> f)
```
modify polymorphically the target of a PLens with an Applicative function

modifyStreamF
```
public abstract F<S,Stream<T>> modifyStreamF(F<A,Stream> f)
```
modify polymorphically the target of a PLens with an Applicative function

modifyP1F
```
public abstract F<S,P1<T>> modifyP1F(F<A,P1> f)
```
modify polymorphically the target of a PLens with an Applicative function

modifyValidationF

public abstract <E> F<S,Validation<E,T>> modifyValidationF(F<A,Validation<E,B>> f)

modify polymorphically the target of a PLens with an Applicative function

modifyV2F
```
public abstract F<S,V2<T>> modifyV2F(F<A,V2> f)
```
modify polymorphically the target of a PLens with an Applicative function

modify
```
public abstract F<S,T> modify(F<A,B> f)
```
modify polymorphically the target of a PLens using a function

sum

public final <S1,T1> PLens<Either<S,S1>,Either<T,T1>,A,B> sum(PLens<S1,T1,A,B> other)

join two PLens with the same target

composeFold

public final <C> Fold<S,C> composeFold(Fold<A,C> other)

compose a PLens with a Fold

composeGetter

public final <C> Getter<S,C> composeGetter(Getter<A,C> other)

compose a PLens with a Getter

composeSetter

public final <C,D> PSetter<S,T,C,D> composeSetter(PSetter<A,B,C,D> other)

compose a PLens with a PSetter

composeTraversal

public final <C,D> PTraversal<S,T,C,D> composeTraversal(PTraversal<A,B,C,D> other)

compose a PLens with a PTraversal

composeOptional

public final <C,D> POptional<S,T,C,D> composeOptional(POptional<A,B,C,D> other)

compose a PLens with an POptional

composePrism

public final <C,D> POptional<S,T,C,D> composePrism(PPrism<A,B,C,D> other)

compose a PLens with a PPrism

composeLens

public final <C,D> PLens<S,T,C,D> composeLens(PLens<A,B,C,D> other)

compose a PLens with a PLens

composeIso

public final <C,D> PLens<S,T,C,D> composeIso(PIso<A,B,C,D> other)

compose a PLens with an PIso

asFold
```
public final Fold<S,A> asFold()
```
view a PLens as a Fold

asGetter
```
public final Getter<S,A> asGetter()
```
view a PLens as a Getter

asSetter
```
public PSetter<S,T,A,B> asSetter()
```
view a PLens as a PSetter

asTraversal

public PTraversal<S,T,A,B> asTraversal()

view a PLens as a PTraversal

asOptional

public POptional<S,T,A,B> asOptional()

view a PLens as an POptional

pId

public static <S,T> PLens<S,T,S,T> pId()

pLens

public static <S,T,A,B> PLens<S,T,A,B> pLens(F<S,A> get,
                                             F<B,F<S,T>> set)

create a PLens using a pair of functions: one to get the target, one to set the target.

Class PLens<S,T,A,B>

Method Summary

Methods inherited from class java.lang.Object

Method Detail

get

set

modifyFunctionF

modifyEitherF

modifyIOF

modifyTrampolineF

modifyPromiseF

modifyListF

modifyOptionF

modifyStreamF

modifyP1F