org.opencastproject.util.data

Class Monadics.IteratorMonadic<A>

java.lang.Object

org.opencastproject.util.data.Monadics.IteratorMonadic<A>

All Implemented Interfaces:

Iterable<A>

Enclosing class:

Monadics

public abstract static class Monadics.IteratorMonadic<A>
extends Object
implements Iterable<A>

The iterator monad.

Method Summary

Modifier and Type	Method and Description
abstract <B> Monadics.IteratorMonadic<B>	bind(Function<A,Iterator<B>> f) Monadic bind.
abstract Monadics.IteratorMonadic<A>	each(Function<A,Void> e) Apply side effect e to each element.
abstract Monadics.IteratorMonadic<A>	eachIndex(Function2<A,Integer,Void> e) Apply side effect e to each element.
abstract List<A>	eval() Evaluate to a list.
abstract boolean	exists(Function<A,Boolean> p) Check if at least one element satisfies predicate p.
abstract Monadics.IteratorMonadic<A>	filter(Function<A,Boolean> p) Retain all elements satisfying predicate p.
<B> Monadics.IteratorMonadic<B>	flatMap(Function<A,Iterator<B>> f) Alias for bind(Function).
abstract <B> Monadics.IteratorMonadic<B>	fmap(Function<A,B> f) Apply f to each element.
abstract <B> B	fold(B zero, Function2<B,A,B> f) Fold the elements applying binary operator f starting with zero.
<B> Monadics.IteratorMonadic<B>	map(Function<A,B> f) Alias for fmap(Function).
abstract <B> Monadics.IteratorMonadic<B>	mapIndex(Function2<A,Integer,B> f) Apply f to each element.
abstract Option<A>	next() Return the head of the iterator.
abstract A	reduce(Function2<A,A,A> f) Reduce the elements applying binary operator f.
abstract Monadics.IteratorMonadic<A>	take(int n) Limit iteration to the first n elements.
abstract Iterator<A>	value() Return the wrapped iterator.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach, iterator, spliterator

Method Detail

map

public final <B> Monadics.IteratorMonadic<B> map(Function<A,B> f)

Alias for fmap(Function).

fmap

public abstract <B> Monadics.IteratorMonadic<B> fmap(Function<A,B> f)

Apply f to each element.

mapIndex

public abstract <B> Monadics.IteratorMonadic<B> mapIndex(Function2<A,Integer,B> f)

Apply f to each element. The function also receives the element's index.

flatMap

public final <B> Monadics.IteratorMonadic<B> flatMap(Function<A,Iterator<B>> f)

Alias for bind(Function).

bind

public abstract <B> Monadics.IteratorMonadic<B> bind(Function<A,Iterator<B>> f)

Monadic bind. Apply f to each elements concatenating the results.

fold

public abstract <B> B fold(B zero,
                           Function2<B,A,B> f)

Fold the elements applying binary operator f starting with zero.

reduce

public abstract A reduce(Function2<A,A,A> f)

Reduce the elements applying binary operator f. The iterator must not be empty.

filter

public abstract Monadics.IteratorMonadic<A> filter(Function<A,Boolean> p)

Retain all elements satisfying predicate p.

exists

public abstract boolean exists(Function<A,Boolean> p)

Check if at least one element satisfies predicate p.

take

public abstract Monadics.IteratorMonadic<A> take(int n)

Limit iteration to the first n elements.

each

public abstract Monadics.IteratorMonadic<A> each(Function<A,Void> e)

Apply side effect e to each element.

eachIndex

public abstract Monadics.IteratorMonadic<A> eachIndex(Function2<A,Integer,Void> e)

Apply side effect e to each element. Indexed version of each(Function).

next

public abstract Option<A> next()

Return the head of the iterator. ATTENTION: This method is not pure since it has the side effect of taking and wrapping the next element of the wrapped iterator.

value

public abstract Iterator<A> value()

Return the wrapped iterator.

eval

public abstract List<A> eval()

Evaluate to a list.