io.atlassian.fugue.optic

Class PLens<S,T,A,B>

java.lang.Object

io.atlassian.fugue.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 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 monomorphic 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

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 Function<S,T>	modify(Function<A,B> f) modify polymorphically the target of a PLens using a function
abstract <L> Function<S,Either<L,T>>	modifyEitherF(Function<A,Either<L,B>> f) modify polymorphically the target of a PLens with an Applicative function
abstract <C> Function<S,Function<C,T>>	modifyFunctionF(Function<A,Function<C,B>> f) modify polymorphically the target of a PLens with an Applicative function
abstract Function<S,Iterable<T>>	modifyIterableF(Function<A,Iterable<B>> f) modify polymorphically the target of a PLens with an Applicative function
abstract Function<S,Option<T>>	modifyOptionF(Function<A,Option<B>> f) modify polymorphically the target of a PLens with an Applicative function
abstract Function<S,Pair<T,T>>	modifyPairF(Function<A,Pair<B,B>> f) modify polymorphically the target of a PLens with an Applicative function
abstract Function<S,Supplier<T>>	modifySupplierF(Function<A,Supplier<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(Function<S,A> get, Function<B,Function<S,T>> set) create a PLens using a pair of functions: one to get the target, one to set the target.
abstract Function<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 Function<S,T> set(B b)

set polymorphically the target of a PLens using a function

modifyFunctionF

public abstract <C> Function<S,Function<C,T>> modifyFunctionF(Function<A,Function<C,B>> f)

modify polymorphically the target of a PLens with an Applicative function

modifyEitherF

public abstract <L> Function<S,Either<L,T>> modifyEitherF(Function<A,Either<L,B>> f)

modify polymorphically the target of a PLens with an Applicative function

modifyOptionF

public abstract Function<S,Option<T>> modifyOptionF(Function<A,Option<B>> f)

modify polymorphically the target of a PLens with an Applicative function

modifyIterableF

public abstract Function<S,Iterable<T>> modifyIterableF(Function<A,Iterable<B>> f)

modify polymorphically the target of a PLens with an Applicative function

modifySupplierF

public abstract Function<S,Supplier<T>> modifySupplierF(Function<A,Supplier<B>> f)

modify polymorphically the target of a PLens with an Applicative function

modifyPairF

public abstract Function<S,Pair<T,T>> modifyPairF(Function<A,Pair<B,B>> f)

modify polymorphically the target of a PLens with an Applicative function

modify

public abstract Function<S,T> modify(Function<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(Function<S,A> get,
                                             Function<B,Function<S,T>> set)

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