net.emaze.dysfunctional

Class Options.Maybes

java.lang.Object

net.emaze.dysfunctional.Options.Maybes

Enclosing class:

Options

public abstract static class Options.Maybes
extends Object

pure, pures, justs, lift, lifts, drop, drops.

Constructor Summary

Constructors

Constructor and Description
Maybes()

Method Summary

Modifier and Type	Method and Description
static <T> T	drop(Optional<T> optional) Transforms a Optional.empty to null, a Optional.of to the wrapped get.
static <T> Iterator<T>	drops(Iterable<Optional<T>> iterable) Creates an iterator transforming Maybes from the source iterable to null when the source element is Nothing, to the wrapped get otherwise.
static <T> Iterator<T>	drops(Iterator<Optional<T>> iterator) Creates an iterator transforming Maybes from the source iterator to null when the source element is Nothing, to the wrapped get otherwise.
static <T> Iterator<T>	drops(Optional<T> first, Optional<T> second) Creates an iterator transformed passed elements such as the become null when the source element is Nothing, the wrapped get otherwise.
static <T> Iterator<T>	drops(Optional<T> first, Optional<T> second, Optional<T> third) Creates an iterator transformed passed elements such as the become null when the source element is Nothing, the wrapped get otherwise.
static <T> Optional<T>	join(Optional<Optional<T>> maybe) Conventional monad join operator.
static <T> Iterator<T>	justs(Iterable<Optional<T>> maybes) Filters nothings out of an Iterable of Optional T, returning an Iterator of T.
static <T> Iterator<T>	justs(Iterator<Optional<T>> maybes) Filters nothings out of an Iterator of Optional T, returning an Iterator of T.
static <T> Iterator<T>	justs(Optional<T> first, Optional<T> second) Filters nothings out of an array of Optional T, returning an Iterator of T.
static <T> Iterator<T>	justs(Optional<T> first, Optional<T> second, Optional<T> third) Filters nothings out of an array of Optional T, returning an Iterator of T.
static <T,R> Function<Optional<T>,Optional<R>>	lift(Function<T,R> function) Transforms a function to another working on maybe monadic values.
static <T> Optional<T>	lift(T value) Transforms a null get to Optional.empty, a non-null get to Optional.of(get)
static <T> Iterator<Optional<T>>	lifts(Iterable<T> iterable) Creates an iterator transforming elements from the source iterable to Optional.empty when the source element is null, to Optional.of(sourceValue) otherwise.
static <T> Iterator<Optional<T>>	lifts(Iterator<T> iterator) Creates an iterator transforming elements from the source iterator to Optional.empty when the source element is null, to Optional.of(sourceValue) otherwise.
static <T> Iterator<Optional<T>>	lifts(T first, T second) Creates an iterator transforming passed values to Optional.empty when the source element is null, to Optional.of(sourceValue) otherwise.
static <T> Iterator<Optional<T>>	lifts(T first, T second, T third) Creates an iterator transforming passed values to Optional.empty when the source element is null, to Optional.of(sourceValue) otherwise.
static <T> Optional<T>	pure(T value) Yields Optional.pure() of a value.
static <T> Iterator<Optional<T>>	pures(Iterable<T> values) Creates an iterator transforming values from the source iterable into pure() Optional monadic values.
static <T> Iterator<Optional<T>>	pures(Iterator<T> values) Creates an iterator transforming values from the source iterator into pure() Optional monadic values.
static <T> Iterator<Optional<T>>	pures(T... values) Creates an iterator yielding values pure() Optional monadic get of the passed values.
static <T> Iterator<Optional<T>>	pures(T value) Creates a singleton iterator yielding pure() Optional monadic get of the passed get.
static <T> Iterator<Optional<T>>	pures(T first, T second) Creates an iterator yielding pure() Optional monadic get of the passed values.
static <T> Iterator<Optional<T>>	pures(T first, T second, T third) Creates an iterator yielding pure() Optional monadic get of the passed values.
static <T> Maybe<T>	toMaybe(Optional<T> optional) Convert an Optional to a Maybe.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Maybes

public Maybes()

Method Detail

toMaybe

public static <T> Maybe<T> toMaybe(Optional<T> optional)

Convert an Optional to a Maybe.

Type Parameters:

T - the optional value type

Parameters:

optional - the value to be converted

Returns:

the resulting maybe

pure

public static <T> Optional<T> pure(T value)

Yields Optional.pure() of a value. (Just get) E.g: Maybes.pure(1) -> Optional.of(1)

Type Parameters:

T - the get type

Parameters:

value - the get to be transformed

Returns:

the resulting maybe

pures

public static <T> Iterator<Optional<T>> pures(Iterator<T> values)

Creates an iterator transforming values from the source iterator into pure() Optional monadic values. E.g: Maybes.pures([1,2,3]) -> [Just 1, Just 2, Just 3]

Type Parameters:

T - the iterator element type

Parameters:

values - the source iterator

Returns:

the resulting iterator

pures

public static <T> Iterator<Optional<T>> pures(Iterable<T> values)

Creates an iterator transforming values from the source iterable into pure() Optional monadic values. E.g: Maybes.pures([1,2,3]) -> [Just 1, Just 2, Just 3]

Type Parameters:

T - the iterable element type

Parameters:

values - the source iterable

Returns:

the resulting iterator

pures

public static <T> Iterator<Optional<T>> pures(T value)

Creates a singleton iterator yielding pure() Optional monadic get of the passed get. E.g: Maybes.pures(1) -> [Just 1]

Type Parameters:

T - the element type

Parameters:

value - the source get

Returns:

the resulting iterator

pures

public static <T> Iterator<Optional<T>> pures(T first,
                                              T second)

Creates an iterator yielding pure() Optional monadic get of the passed values. E.g: Maybes.pures(1, 2) -> [Just 1, Just 2]

Type Parameters:

T - the elements type

Parameters:

first - the first element

second - the second element

Returns:

the resulting iterator

pures

public static <T> Iterator<Optional<T>> pures(T first,
                                              T second,
                                              T third)

Creates an iterator yielding pure() Optional monadic get of the passed values. E.g: Maybes.pures(1, 2, 3) -> [Just 1, Just 2, Just 3]

Type Parameters:

T - the elements type

Parameters:

first - the first element

second - the second element

third - the third element

Returns:

the resulting iterator

pures

public static <T> Iterator<Optional<T>> pures(T... values)

Creates an iterator yielding values pure() Optional monadic get of the passed values. E.g: Maybes.pures(1, 2, 3, 4) -> [Just 1, Just 2, Just 3, Just 4]

Type Parameters:

T - the array element type

Parameters:

values - the source array

Returns:

the resulting array

justs

public static <T> Iterator<T> justs(Iterator<Optional<T>> maybes)

Filters nothings out of an Iterator of Optional T, returning an Iterator of T. E.g: Maybes.justs([Just 1, Nothing, Just null]) -> [1, null]

Type Parameters:

T - the Optional type parameter

Parameters:

maybes - an iterator of Optional

Returns:

the resulting iterator

justs

public static <T> Iterator<T> justs(Iterable<Optional<T>> maybes)

Filters nothings out of an Iterable of Optional T, returning an Iterator of T. E.g: Maybes.justs([Just 1, Nothing, Just null]) -> [1, null]

Type Parameters:

T - the Optional type parameter

Parameters:

maybes - an iterable of Optional

Returns:

the resulting iterator

justs

public static <T> Iterator<T> justs(Optional<T> first,
                                    Optional<T> second)

Filters nothings out of an array of Optional T, returning an Iterator of T. E.g: Maybes.justs([Nothing, Just null]) -> [null]

Type Parameters:

T - the Optional type parameter

Parameters:

first - the first element

second - the second element

Returns:

the resulting iterator

justs

public static <T> Iterator<T> justs(Optional<T> first,
                                    Optional<T> second,
                                    Optional<T> third)

Filters nothings out of an array of Optional T, returning an Iterator of T. E.g: Maybes.justs([Just 1, Nothing, Just null]) -> [1, null]

Type Parameters:

T - the Optional type parameter

Parameters:

first - the first element

second - the second element

third - the third element

Returns:

the resulting iterator

lift

public static <T> Optional<T> lift(T value)

Transforms a null get to Optional.empty, a non-null get to Optional.of(get)

Type Parameters:

T - the get type parameter

Parameters:

value - the get to be lifted

Returns:

a Optional

lift

public static <T,R> Function<Optional<T>,Optional<R>> lift(Function<T,R> function)

Transforms a function to another working on maybe monadic values.

Type Parameters:

T - the function parameter type

R - the function return type

Parameters:

function - the function to be lifted

Returns:

the transformed function

lifts

public static <T> Iterator<Optional<T>> lifts(Iterator<T> iterator)

Creates an iterator transforming elements from the source iterator to Optional.empty when the source element is null, to Optional.of(sourceValue) otherwise. E.g: Maybes.lift([null, 1, 2]) -> [Nothing, Just 1, Just 2]

Type Parameters:

T - the get type parameter

Parameters:

iterator - the iterator to be lifted

Returns:

the resulting iterator

lifts

public static <T> Iterator<Optional<T>> lifts(Iterable<T> iterable)

Creates an iterator transforming elements from the source iterable to Optional.empty when the source element is null, to Optional.of(sourceValue) otherwise. E.g: Maybes.lift([null, 1, 2]) -> [Nothing, Just 1, Just 2]

Type Parameters:

T - the get type parameter

Parameters:

iterable - the iterable to be lifted

Returns:

the resulting iterator

lifts

public static <T> Iterator<Optional<T>> lifts(T first,
                                              T second)

Creates an iterator transforming passed values to Optional.empty when the source element is null, to Optional.of(sourceValue) otherwise. E.g: Maybes.lift(null, 1) -> [Nothing, Just 1]

Type Parameters:

T - the get type

Parameters:

first - the first element

second - the second element

Returns:

the resulting iterator

lifts

public static <T> Iterator<Optional<T>> lifts(T first,
                                              T second,
                                              T third)

Creates an iterator transforming passed values to Optional.empty when the source element is null, to Optional.of(sourceValue) otherwise. E.g: Maybes.lift(null, 1, 3) -> [Nothing, Just 1, Just 3]

Type Parameters:

T - the get type

Parameters:

first - the first element

second - the second element

third - the third element

Returns:

the resulting iterator

drop

public static <T> T drop(Optional<T> optional)

Transforms a Optional.empty to null, a Optional.of to the wrapped get. E.g: Maybes.drop(Just 1) -> 1 Maybes.drop(Nothing) -> null

Type Parameters:

T - the get type parameter

Parameters:

optional - the right to be dropped

Returns:

null or a get

drops

public static <T> Iterator<T> drops(Iterator<Optional<T>> iterator)

Creates an iterator transforming Maybes from the source iterator to null when the source element is Nothing, to the wrapped get otherwise. E.g: Maybes.drops([Just null, Nothing, Just 3]) -> [null, null, 3]

Type Parameters:

T - the get type parameter

Parameters:

iterator - the iterator to be dropped

Returns:

an iterator of T

drops

public static <T> Iterator<T> drops(Iterable<Optional<T>> iterable)

Creates an iterator transforming Maybes from the source iterable to null when the source element is Nothing, to the wrapped get otherwise. E.g: Maybes.drops([Just null, Nothing, Just 3]) -> [null, null, 3]

Type Parameters:

T - the get type parameter

Parameters:

iterable - the Iterable to be dropped

Returns:

the resulting iterator

drops

public static <T> Iterator<T> drops(Optional<T> first,
                                    Optional<T> second)

Creates an iterator transformed passed elements such as the become null when the source element is Nothing, the wrapped get otherwise. E.g: Maybes.drops([Just null, Just 3]) -> [null, 3]

Type Parameters:

T - the get type parameter

Parameters:

first - the first maybe

second - the second maybe

Returns:

the resulting iterator

drops

public static <T> Iterator<T> drops(Optional<T> first,
                                    Optional<T> second,
                                    Optional<T> third)

Creates an iterator transformed passed elements such as the become null when the source element is Nothing, the wrapped get otherwise. E.g: Maybes.drops([Just null, Just 3]) -> [null, 3]

Type Parameters:

T - the get type parameter

Parameters:

first - the first maybe

second - the second maybe

third - the third maybe

Returns:

the resulting iterator

join

public static <T> Optional<T> join(Optional<Optional<T>> maybe)

Conventional monad join operator. It is used to remove one level of monadic structure, projecting its bound argument into the outer level.

Type Parameters:

T - the get type parameter

Parameters:

maybe - the source monad

Returns:

the unwrapped monad