Package com.jnape.palatable.lambda.optics

Interface Prism<S,T,A,B>

Type Parameters:

S - the input that might fail to map to its output

T - the guaranteed output

A - the output that might fail to be produced

B - the input that guarantees its output

All Superinterfaces:

Applicative<T,Prism<S,?,A,B>>, Contravariant<S,Profunctor<?,T,Prism<?,?,A,B>>>, Functor<T,Prism<S,?,A,B>>, Monad<T,Prism<S,?,A,B>>, MonadRec<T,Prism<S,?,A,B>>, Optic<Cocartesian<?,?,?>,Identity<?>,S,T,A,B>, Profunctor<S,T,Prism<?,?,A,B>>, ProtoOptic<Cocartesian<?,?,?>,S,T,A,B>

All Known Subinterfaces:

Prism.Simple<S,A>

Functional Interface:

This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@FunctionalInterface
public interface Prism<S,T,A,B>
extends ProtoOptic<Cocartesian<?,?,?>,S,T,A,B>, MonadRec<T,Prism<S,?,A,B>>, Profunctor<S,T,Prism<?,?,A,B>>

Prisms are Isos that can fail in one direction. Example:

 
 Prism<String, String, Integer, Integer> parseInt =
     prism(str -> Either.trying(() -> Integer.parseInt(str),
                                constantly(str)),
           Object::toString);

 String         str   = view(re(parseInt), 123); // "123"
 Maybe<Integer> works = view(pre(parseInt), "123"); // Just 123
 Maybe<Integer> fails = view(pre(parseInt), "foo"); // Nothing
 
 

Note that because a Prism might fail in one direction, it cannot be immediately used for viewing; however, the combinators re, pre, and matching can all be used to provide the additional context to a Prism so it can be used for viewing.

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static interface	Prism.Simple<S,A>	A convenience type with a simplified type signature for common prism with unified S/T and A/B types.

Method Summary

Modifier and Type	Method	Description
default <Z,C> Prism<S,T,Z,C>	andThen(ProtoOptic<? super Cocartesian<?,?,?>,A,B,Z,C> f)	Left-to-right composition of proto-optics.
default <CoP extends Profunctor<?,?,? extends Cocartesian<?,?,?>>,CoF extends Functor<?,? extends Identity<?>>,FB extends Functor<B,? extends CoF>,FT extends Functor<T,? extends CoF>,PAFB extends Profunctor<A,FB,? extends CoP>,PSFT extends Profunctor<S,FT,? extends CoP>> PSFT	apply(PAFB pafb)	The polymorphic arrow between profunctors in this optic interface.
default <R,U> Prism<R,U,A,B>	compose(ProtoOptic<? super Cocartesian<?,?,?>,R,U,S,T> g)	Right-to-Left composition of proto-optics.
default <R> Prism<R,T,A,B>	contraMap(Fn1<? super R,? extends S> fn)	Contravariantly map A <- B.
default <R,U> Prism<R,U,A,B>	diMap(Fn1<? super R,? extends S> lFn, Fn1<? super T,? extends U> rFn)	Dually map contravariantly over the left parameter and covariantly over the right parameter.
default <R> Prism<R,T,A,B>	diMapL(Fn1<? super R,? extends S> fn)	Contravariantly map over the left parameter.
default <U> Prism<S,U,A,B>	diMapR(Fn1<? super T,? extends U> fn)	Covariantly map over the right parameter.
default <U> Prism<S,U,A,B>	discardL(Applicative<U,Prism<S,?,A,B>> appB)	Sequence both this Applicative and appB, discarding this Applicative's result and returning appB.
default <U> Prism<S,T,A,B>	discardR(Applicative<U,Prism<S,?,A,B>> appB)	Sequence both this Applicative and appB, discarding appB's result and returning this Applicative.
default <U> Prism<S,U,A,B>	flatMap(Fn1<? super T,? extends Monad<U,Prism<S,?,A,B>>> f)	Chain dependent computations that may continue or short-circuit based on previous results.
default <U> Prism<S,U,A,B>	fmap(Fn1<? super T,? extends U> fn)	Covariantly transmute this functor's parameter using the given mapping function.
static <S,A,B> Prism<S,S,A,B>	fromPartial(Fn1<? super S,? extends A> partialSa, Fn1<? super B,? extends S> bs)	Static factory method for creating a Prism from a partial function S -> A and a total function B -> S.
default <U> Lazy<Prism<S,U,A,B>>	lazyZip(Lazy<? extends Applicative<Fn1<? super T,? extends U>,Prism<S,?,A,B>>> lazyAppFn)	Given a lazy instance of this applicative over a mapping function, "zip" the two instances together using whatever application semantics the current applicative supports.
default <C> Prism<S,T,C,B>	mapA(Fn1<? super A,? extends C> fn)	Covariantly map A to C, yielding a new optic.
default <Z> Prism<S,T,A,Z>	mapB(Fn1<? super Z,? extends B> fn)	Contravariantly map B to Z, yielding a new optic.
default <R> Prism<R,T,A,B>	mapS(Fn1<? super R,? extends S> fn)	Contravariantly map S to R, yielding a new optic.
default <U> Prism<S,U,A,B>	mapT(Fn1<? super T,? extends U> fn)	Covariantly map T to U, yielding a new optic.
static <S,T,A,B> Prism<S,T,A,B>	prism(Fn1<? super S,? extends CoProduct2<T,A,?>> sta, Fn1<? super B,? extends T> bt)	Static factory method for creating a Prism given a mapping from S -> Either<T, A> and a mapping from B -> T.
static <S,T,A,B> Prism<S,T,A,B>	prism(Optic<? super Cocartesian<?,?,?>,? super Functor<?,?>,S,T,A,B> optic)	Promote an Optic with compatible bounds to an Prism.
static <S,T,A,B> Prism<S,T,A,B>	prism(ProtoOptic<? super Cocartesian<?,?,?>,S,T,A,B> protoOptic)	Promote a ProtoOptic with compatible bounds to an Prism.
default <U> Prism<S,U,A,B>	pure(U u)	Lift the value b into this applicative functor.
static <S,A,B> Pure<Prism<S,?,A,B>>	purePrism()	The canonical Pure instance for Prism.
static <S,A> Prism.Simple<S,A>	simplePrism(Fn1<? super S,? extends Maybe<A>> sMaybeA, Fn1<? super A,? extends S> as)	Static factory method for creating a simple Prism from a function and its potentially failing inverse.
default <U> Prism<S,U,A,B>	trampolineM(Fn1<? super T,? extends MonadRec<RecursiveResult<T,U>,Prism<S,?,A,B>>> fn)	Given some operation yielding a RecursiveResult inside this MonadRec, internally trampoline the operation until it yields a termination instruction.
default Tuple2<Fn1<? super B,? extends T>,Fn1<? super S,? extends Either<T,A>>>	unPrism()	Recover the two mappings encapsulated by this Prism by sending it through a Market.
default <U> Prism<S,U,A,B>	zip(Applicative<Fn1<? super T,? extends U>,Prism<S,?,A,B>> appFn)	Given another instance of this applicative over a mapping function, "zip" the two instances together using whatever application semantics the current applicative supports.

Methods inherited from interface com.jnape.palatable.lambda.functor.Functor

coerce

Methods inherited from interface com.jnape.palatable.lambda.optics.Optic

andThen, compose, monomorphize

Methods inherited from interface com.jnape.palatable.lambda.optics.ProtoOptic

toOptic

Method Detail

unPrism

default Tuple2<Fn1<? super B,? extends T>,Fn1<? super S,? extends Either<T,A>>> unPrism()

Recover the two mappings encapsulated by this Prism by sending it through a Market.

Returns:

a tuple of the two mappings encapsulated by this Prism

apply

default <CoP extends Profunctor<?,?,? extends Cocartesian<?,?,?>>,CoF extends Functor<?,? extends Identity<?>>,FB extends Functor<B,? extends CoF>,FT extends Functor<T,? extends CoF>,PAFB extends Profunctor<A,FB,? extends CoP>,PSFT extends Profunctor<S,FT,? extends CoP>> PSFT apply(PAFB pafb)

The polymorphic arrow between profunctors in this optic interface.

Specified by:

apply in interface Optic<Cocartesian<?,?,?>,Identity<?>,S,T,A,B>

Specified by:

apply in interface ProtoOptic<Cocartesian<?,?,?>,S,T,A,B>

Type Parameters:

CoP - the profunctor type constraint witnessed by the application of this optic

CoF - the functor type constraint witnessed by the application of this optic

FB - the covariant parameter type of the input profunctor

FT - the covariant parameter type of the output profunctor

PAFB - the full input type

PSFT - the full output type

Parameters:

pafb - the input

Returns:

the output profunctor

andThen

default <Z,C> Prism<S,T,Z,C> andThen(ProtoOptic<? super Cocartesian<?,?,?>,A,B,Z,C> f)

Left-to-right composition of proto-optics. Requires compatibility between S and T.

Specified by:

andThen in interface ProtoOptic<Cocartesian<?,?,?>,S,T,A,B>

Type Parameters:

Z - the new left side of the input profunctor

C - the new right side's functor embedding of the input profunctor

Parameters:

f - the other proto-optic

Returns:

the composed proto-optic

compose

default <R,U> Prism<R,U,A,B> compose(ProtoOptic<? super Cocartesian<?,?,?>,R,U,S,T> g)

Right-to-Left composition of proto-optics. Requires compatibility between A and B.

Specified by:

compose in interface ProtoOptic<Cocartesian<?,?,?>,S,T,A,B>

Type Parameters:

R - the new left side of the output profunctor

U - the new right side's functor embedding of the output profunctor

Parameters:

g - the other proto-optic

Returns:

the composed proto-optic

mapS

default <R> Prism<R,T,A,B> mapS(Fn1<? super R,? extends S> fn)

Contravariantly map S to R, yielding a new optic.

Specified by:

mapS in interface Optic<Cocartesian<?,?,?>,Identity<?>,S,T,A,B>

Specified by:

mapS in interface ProtoOptic<Cocartesian<?,?,?>,S,T,A,B>

Type Parameters:

R - the new left side of the output profunctor

Parameters:

fn - the mapping function

Returns:

the new optic

mapT

default <U> Prism<S,U,A,B> mapT(Fn1<? super T,? extends U> fn)

Covariantly map T to U, yielding a new optic.

Specified by:

mapT in interface Optic<Cocartesian<?,?,?>,Identity<?>,S,T,A,B>

Specified by:

mapT in interface ProtoOptic<Cocartesian<?,?,?>,S,T,A,B>

Type Parameters:

U - the new right side's functor embedding of the output profunctor

Parameters:

fn - the mapping function

Returns:

the new optic

mapA

default <C> Prism<S,T,C,B> mapA(Fn1<? super A,? extends C> fn)

Covariantly map A to C, yielding a new optic.

Specified by:

mapA in interface Optic<Cocartesian<?,?,?>,Identity<?>,S,T,A,B>

Specified by:

mapA in interface ProtoOptic<Cocartesian<?,?,?>,S,T,A,B>

Type Parameters:

C - the new left side of the input profunctor

Parameters:

fn - the mapping function

Returns:

the new optic

mapB

default <Z> Prism<S,T,A,Z> mapB(Fn1<? super Z,? extends B> fn)

Contravariantly map B to Z, yielding a new optic.

Specified by:

mapB in interface Optic<Cocartesian<?,?,?>,Identity<?>,S,T,A,B>

Specified by:

mapB in interface ProtoOptic<Cocartesian<?,?,?>,S,T,A,B>

Type Parameters:

Z - the new right side's functor embedding of the input profunctor

Parameters:

fn - the mapping function

Returns:

the new optic

pure

default <U> Prism<S,U,A,B> pure(U u)

Lift the value b into this applicative functor.

Specified by:

pure in interface Applicative<S,T>

Specified by:

pure in interface Monad<S,T>

Specified by:

pure in interface MonadRec<S,T>

Type Parameters:

U - the type of the returned applicative's parameter

Parameters:

u - the value

Returns:

an instance of this applicative over b

flatMap

default <U> Prism<S,U,A,B> flatMap(Fn1<? super T,? extends Monad<U,Prism<S,?,A,B>>> f)

Chain dependent computations that may continue or short-circuit based on previous results.

Specified by:

flatMap in interface Monad<S,T>

Specified by:

flatMap in interface MonadRec<S,T>

Type Parameters:

U - the resulting monad parameter type

Parameters:

f - the dependent computation over A

Returns:

the new monad instance

fmap

default <U> Prism<S,U,A,B> fmap(Fn1<? super T,? extends U> fn)

Covariantly transmute this functor's parameter using the given mapping function. Generally this method is specialized to return an instance of the class implementing Functor.

Specified by:

fmap in interface Applicative<S,T>

Specified by:

fmap in interface Functor<S,T>

Specified by:

fmap in interface Monad<S,T>

Specified by:

fmap in interface MonadRec<S,T>

Type Parameters:

U - the new parameter type

Parameters:

fn - the mapping function

Returns:

a functor over B (the new parameter type)

zip

default <U> Prism<S,U,A,B> zip(Applicative<Fn1<? super T,? extends U>,Prism<S,?,A,B>> appFn)

Given another instance of this applicative over a mapping function, "zip" the two instances together using whatever application semantics the current applicative supports.

Specified by:

zip in interface Applicative<S,T>

Specified by:

zip in interface Monad<S,T>

Specified by:

zip in interface MonadRec<S,T>

Type Parameters:

U - the resulting applicative parameter type

Parameters:

appFn - the other applicative instance

Returns:

the mapped applicative

lazyZip

default <U> Lazy<Prism<S,U,A,B>> lazyZip(Lazy<? extends Applicative<Fn1<? super T,? extends U>,Prism<S,?,A,B>>> lazyAppFn)

Given a lazy instance of this applicative over a mapping function, "zip" the two instances together using whatever application semantics the current applicative supports. This is useful for applicatives that support lazy evaluation and early termination.

Specified by:

lazyZip in interface Applicative<S,T>

Specified by:

lazyZip in interface Monad<S,T>

Specified by:

lazyZip in interface MonadRec<S,T>

Type Parameters:

U - the resulting applicative parameter type

Parameters:

lazyAppFn - the lazy other applicative instance

Returns:

the mapped applicative

See Also:

Maybe, Either

discardL

default <U> Prism<S,U,A,B> discardL(Applicative<U,Prism<S,?,A,B>> appB)

Sequence both this Applicative and appB, discarding this Applicative's result and returning appB. This is generally useful for sequentially performing side-effects.

Specified by:

discardL in interface Applicative<S,T>

Specified by:

discardL in interface Monad<S,T>

Specified by:

discardL in interface MonadRec<S,T>

Type Parameters:

U - the type of the returned Applicative's parameter

Parameters:

appB - the other Applicative

Returns:

appB

discardR

default <U> Prism<S,T,A,B> discardR(Applicative<U,Prism<S,?,A,B>> appB)

Sequence both this Applicative and appB, discarding appB's result and returning this Applicative. This is generally useful for sequentially performing side-effects.

Specified by:

discardR in interface Applicative<S,T>

Specified by:

discardR in interface Monad<S,T>

Specified by:

discardR in interface MonadRec<S,T>

Type Parameters:

U - the type of appB's parameter

Parameters:

appB - the other Applicative

Returns:

this Applicative

trampolineM

default <U> Prism<S,U,A,B> trampolineM(Fn1<? super T,? extends MonadRec<RecursiveResult<T,U>,Prism<S,?,A,B>>> fn)

Given some operation yielding a RecursiveResult inside this MonadRec, internally trampoline the operation until it yields a termination instruction.

Stack-safety depends on implementations guaranteeing that the growth of the call stack is a constant factor independent of the number of invocations of the operation. For various examples of how this can be achieved in stereotypical circumstances, see the referenced types.

Specified by:

trampolineM in interface MonadRec<S,T>

Type Parameters:

U - the ultimate resulting carrier type

Parameters:

fn - the function to internally trampoline

Returns:

the trampolined MonadRec

See Also:

for a basic implementation, for a implementation, for an implementation leveraging an already stack-safe , for a implementation

diMap

default <R,U> Prism<R,U,A,B> diMap(Fn1<? super R,? extends S> lFn,
                                                           Fn1<? super T,? extends U> rFn)

Dually map contravariantly over the left parameter and covariantly over the right parameter. This is isomorphic to diMapL(lFn).diMapR(rFn).

Specified by:

diMap in interface Profunctor<S,T,A>

Type Parameters:

R - the new left parameter type

U - the new right parameter type

Parameters:

lFn - the left parameter mapping function

rFn - the right parameter mapping function

Returns:

a profunctor over Z (the new left parameter type) and C (the new right parameter type)

diMapL

default <R> Prism<R,T,A,B> diMapL(Fn1<? super R,? extends S> fn)

Contravariantly map over the left parameter.

Specified by:

diMapL in interface Profunctor<S,T,A>

Type Parameters:

R - the new left parameter type

Parameters:

fn - the mapping function

Returns:

a profunctor over Z (the new left parameter type) and C (the same right parameter type)

diMapR

default <U> Prism<S,U,A,B> diMapR(Fn1<? super T,? extends U> fn)

Covariantly map over the right parameter. For all profunctors that are also functors, it should hold that diMapR(f) == fmap(f).

Specified by:

diMapR in interface Profunctor<S,T,A>

Type Parameters:

U - the new right parameter type

Parameters:

fn - the mapping function

Returns:

a profunctor over A (the same left parameter type) and C (the new right parameter type)

contraMap

default <R> Prism<R,T,A,B> contraMap(Fn1<? super R,? extends S> fn)

Contravariantly map A <- B.

Specified by:

contraMap in interface Contravariant<S,T>

Specified by:

contraMap in interface Profunctor<S,T,A>

Type Parameters:

R - the new parameter type

Parameters:

fn - the mapping function

Returns:

the mapped Contravariant functor instance

prism

static <S,T,A,B> Prism<S,T,A,B> prism(Fn1<? super S,? extends CoProduct2<T,A,?>> sta,
                                                                          Fn1<? super B,? extends T> bt)

Static factory method for creating a Prism given a mapping from S -> Either<T, A> and a mapping from B -> T.

Type Parameters:

S - the input that might fail to map to its output

T - the guaranteed output

A - the output that might fail to be produced

B - the input that guarantees its output

Parameters:

sta - the mapping from S -> Either<T, A>

bt - the mapping from B -> T

Returns:

the Prism

prism

static <S,T,A,B> Prism<S,T,A,B> prism(ProtoOptic<? super Cocartesian<?,?,?>,S,T,A,B> protoOptic)

Promote a ProtoOptic with compatible bounds to an Prism.

Type Parameters:

S - the input that might fail to map to its output

T - the guaranteed output

A - the output that might fail to be produced

B - the input that guarantees its output

Parameters:

protoOptic - the ProtoOptic

Returns:

the Prism

prism

static <S,T,A,B> Prism<S,T,A,B> prism(Optic<? super Cocartesian<?,?,?>,? super Functor<?,?>,S,T,A,B> optic)

Promote an Optic with compatible bounds to an Prism. Note that because the Optic must guarantee an unbounded Functor constraint in order to satisfy any future covariant constraint, the resulting prism's toOptic method will never need to consult its given lifting function.

Type Parameters:

S - the input that might fail to map to its output

T - the guaranteed output

A - the output that might fail to be produced

B - the input that guarantees its output

Parameters:

optic - the Optic

Returns:

the Prism

simplePrism

static <S,A> Prism.Simple<S,A> simplePrism(Fn1<? super S,? extends Maybe<A>> sMaybeA,
                                                       Fn1<? super A,? extends S> as)

Static factory method for creating a simple Prism from a function and its potentially failing inverse.

Type Parameters:

S - the input that might fail to map to its output and the guaranteed output from the other direction

A - the output that might fail to be produced and the input that guarantees its output in the other direction

Parameters:

sMaybeA - a partial mapping from S -> A

as - a total mapping from A -> S

Returns:

the simple prism

fromPartial

static <S,A,B> Prism<S,S,A,B> fromPartial(Fn1<? super S,? extends A> partialSa,
                                                                        Fn1<? super B,? extends S> bs)

Static factory method for creating a Prism from a partial function S -> A and a total function B -> S.

Type Parameters:

S - the input that might fail to map to its output and the guaranteed output from the other direction

A - the output that might fail to be produced

B - the input that guarantees its output in the other direction

Parameters:

partialSa - the partial direction

bs - the reverse total direction

Returns:

the Prism

purePrism

static <S,A,B> Pure<Prism<S,?,A,B>> purePrism()

The canonical Pure instance for Prism.

Type Parameters:

S - the input that might fail to map to its output

A - the output that might fail to be produced

B - the input that guarantees its output

Returns:

the Pure instance