no.motif.single

Interface A<V>

Type Parameters:

V -

All Superinterfaces:

Appendable<V>, Filterable<V>, Iterable<V>, Mappable<V>, Prependable<V>, Serializable

All Known Implementing Classes:

Optional.Some

public interface A<V>
extends Iterable<V>, Mappable<V>, Filterable<V>, Appendable<V>, Prependable<V>, Serializable

This is a V, i.e. A<V>, a singular value of type V which is always considered as "present". Most of the operations from Optional are available, except for the ones implying that the value may not be present. Unlike Optional, calling get() on A<V> will never throw an exception.

Method Summary

Modifier and Type	Method and Description
Optional<V>	asOptional()
Optional<V>	filter(Predicate<? super V> filter) Provide a predicate that evaluates which element(s) to be included.
V	get()
<O> Optional<O>	map(Fn<? super V,O> mapper) Map the contained to another value.
<O> Optional<O>	map(Predicate<? super O> isPresent, Fn<? super V,O> mapper) Map the value to another value.
<O> Elements<O>	split(Fn<? super V,? extends Iterable<O>> splitter) Split the value into multiple values.

Methods inherited from interface no.motif.types.Appendable

append, append

Methods inherited from interface no.motif.types.Prependable

prepend, prepend

Methods inherited from interface java.lang.Iterable

forEach, iterator, spliterator

Method Detail

get

V get()

Returns:

the contained value. Unlike Optional, calling get() on A<V> will never throw an exception.

map

<O> Optional<O> map(Fn<? super V,O> mapper)

Map the contained to another value. This will yield an Optional of the other type, which is "present" for any non-null value yielded from the mapping.

Specified by:

map in interface Mappable<V>

Parameters:

mapper - The function to apply.

Returns:

The result from the function application.

map

<O> Optional<O> map(Predicate<? super O> isPresent,
                    Fn<? super V,O> mapper)

Map the value to another value. This will yield an Optional of the other type. The given Predicate decides if the resulting value is "present".

See Also:

map(Fn)

filter

Optional<V> filter(Predicate<? super V> filter)

Description copied from interface: Filterable

Provide a predicate that evaluates which element(s) to be included.

Specified by:

filter in interface Filterable<V>

Parameters:

filter - The predicate, when evaluates an element to false, will exclude that element.

Returns:

the filtered elements.

split

<O> Elements<O> split(Fn<? super V,? extends Iterable<O>> splitter)

Split the value into multiple values.

Due to limitations of the type system in Java, it is not possible to overload this method to accept both functions yielding an Iterable (as this method does) as well as functions yielding an array. It is recommended to prefer implementing functions yielding Iterables. If implementing an array-yielding function is most appropriate for your case, and you wish to use the function to split an optional value using this method, it is possible to adapt the function using Iterate.toIterable(Fn)

Parameters:

splitter - a function yielding an iterable.

Returns:

the elements.

asOptional

Optional<V> asOptional()

Returns:

this, typed as an Optional which is present regardless of the contained value.