Package io.vavr.collection

Interface Set<T>

Type Parameters:

T - component type

All Superinterfaces:

Foldable<T>, java.util.function.Function<T,java.lang.Boolean>, Function1<T,java.lang.Boolean>, java.lang.Iterable<T>, java.io.Serializable, Traversable<T>, Value<T>

All Known Subinterfaces:

BitSet<T>, SortedSet<T>

All Known Implementing Classes:

BitSetModule.AbstractBitSet, BitSetModule.BitSet1, BitSetModule.BitSet2, BitSetModule.BitSetN, HashSet, LinkedHashSet, TreeSet

public interface Set<T>
extends Traversable<T>, Function1<T,java.lang.Boolean>, java.io.Serializable

An immutable Set interface.

Vavr Set implementations generally support null elements, but SortedSet implementations require a Comparator, which may not support null.

Supports standard set operations like addition, removal, union, intersection, and difference. Can be converted to a Java Set.

Field Summary

Fields

Modifier and Type	Field	Description
static long	serialVersionUID	The serial version UID for serialization.

Method Summary

Modifier and Type	Method	Description
Set<T>	add(T element)	Returns a new set containing all elements of this set plus the given element, if it was not already present.
Set<T>	addAll(@NonNull java.lang.Iterable<? extends T> elements)	Returns a new set containing all elements of this set plus the given elements, excluding duplicates.
default java.lang.Boolean	apply(T element)	Deprecated. Will be removed
<R> Set<R>	collect(@NonNull PartialFunction<? super T,? extends R> partialFunction)	Applies a PartialFunction to all elements that are defined for it and collects the results.
boolean	contains(T element)	Shortcut for exists(e -> Objects.equals(e, element)), tests if the given element is contained.
Set<T>	diff(@NonNull Set<? extends T> that)	Returns a new set containing all elements of this set except those in the given set.
Set<T>	distinct()	Returns a new Traversable containing the elements of this instance with all duplicates removed.
Set<T>	distinctBy(@NonNull java.util.Comparator<? super T> comparator)	Returns a new Traversable containing the elements of this instance without duplicates, as determined by the given comparator.
<U> Set<T>	distinctBy(@NonNull java.util.function.Function<? super T,? extends U> keyExtractor)	Returns a new Traversable containing the elements of this instance without duplicates, based on keys extracted from elements using keyExtractor.
Set<T>	drop(int n)	Returns a new Traversable without the first n elements, or an empty instance if this contains fewer than n elements.
Set<T>	dropRight(int n)	Returns a new Traversable without the last n elements, or an empty instance if this contains fewer than n elements.
Set<T>	dropUntil(@NonNull java.util.function.Predicate<? super T> predicate)	Returns a new Traversable starting from the first element that satisfies the given predicate, dropping all preceding elements.
Set<T>	dropWhile(@NonNull java.util.function.Predicate<? super T> predicate)	Returns a new Traversable starting from the first element that does not satisfy the given predicate, dropping all preceding elements.
Set<T>	filter(@NonNull java.util.function.Predicate<? super T> predicate)	Returns a new traversable containing only the elements that satisfy the given predicate.
<U> Set<U>	flatMap(@NonNull java.util.function.Function<? super T,? extends java.lang.Iterable<? extends U>> mapper)	Transforms each element of this Traversable into an Iterable of elements and flattens the resulting iterables into a single Traversable.
<C> Map<C,? extends Set<T>>	groupBy(@NonNull java.util.function.Function<? super T,? extends C> classifier)	Groups elements of this Traversable based on a classifier function.
Iterator<? extends Set<T>>	grouped(int size)	Splits this Traversable into consecutive blocks of the given size.
Set<T>	init()	Returns all elements of this Traversable except the last one.
Option<? extends Set<T>>	initOption()	Returns all elements of this Traversable except the last one, wrapped in an Option.
Set<T>	intersect(@NonNull Set<? extends T> that)	Returns a new set containing only the elements present in both this set and the given set.
default boolean	isDistinct()	Indicates whether this Traversable may contain only distinct elements.
@NonNull Iterator<T>	iterator()	Returns an iterator over the elements of this Traversable, implemented via Traversable.head() and Traversable.tail().
int	length()	Returns the number of elements in this Traversable.
<U> Set<U>	map(@NonNull java.util.function.Function<? super T,? extends U> mapper)	Transforms the elements of this Traversable to a new type, preserving order if defined.
default <U> Set<U>	mapTo(U value)	Maps the underlying value to another fixed value.
default Set<java.lang.Void>	mapToVoid()	Maps the underlying value to Void
static <T> Set<T>	narrow(Set<? extends T> set)	Narrows a widened Set<? extends T> to Set<T> by performing a type-safe cast.
Set<T>	orElse(@NonNull java.lang.Iterable<? extends T> other)	Returns this Traversable if it is non-empty; otherwise, returns the given alternative.
Set<T>	orElse(@NonNull java.util.function.Supplier<? extends java.lang.Iterable<? extends T>> supplier)	Returns this Traversable if it is non-empty; otherwise, returns the result of evaluating the given supplier.
Tuple2<? extends Set<T>,? extends Set<T>>	partition(@NonNull java.util.function.Predicate<? super T> predicate)	Splits this Traversable into two partitions according to a predicate.
Set<T>	peek(@NonNull java.util.function.Consumer<? super T> action)	Performs the given action on the first element if this is an eager implementation.
Set<T>	reject(@NonNull java.util.function.Predicate<? super T> predicate)	Returns a new traversable containing only the elements that do not satisfy the given predicate.
Set<T>	remove(T element)	Returns a new set with the given element removed, if it was present.
Set<T>	removeAll(@NonNull java.lang.Iterable<? extends T> elements)	Returns a new set with all given elements removed, if present.
Set<T>	replace(T currentElement, T newElement)	Replaces the first occurrence of currentElement with newElement, if it exists.
Set<T>	replaceAll(T currentElement, T newElement)	Replaces all occurrences of currentElement with newElement.
Set<T>	retainAll(@NonNull java.lang.Iterable<? extends T> elements)	Retains only the elements from this Traversable that are contained in the given elements.
Set<T>	scan(T zero, @NonNull java.util.function.BiFunction<? super T,? super T,? extends T> operation)	Computes a prefix scan of the elements of this Traversable.
<U> Set<U>	scanLeft(U zero, @NonNull java.util.function.BiFunction<? super U,? super T,? extends U> operation)	Produces a collection containing cumulative results of applying the operator from left to right.
<U> Set<U>	scanRight(U zero, @NonNull java.util.function.BiFunction<? super T,? super U,? extends U> operation)	Produces a collection containing cumulative results of applying the operator from right to left.
Iterator<? extends Set<T>>	slideBy(@NonNull java.util.function.Function<? super T,?> classifier)	Partitions this Traversable into consecutive non-overlapping windows according to a classification function.
Iterator<? extends Set<T>>	sliding(int size)	Slides a window of a given size over this Traversable with a step size of 1.
Iterator<? extends Set<T>>	sliding(int size, int step)	Slides a window of a specific size with a given step over this Traversable.
Tuple2<? extends Set<T>,? extends Set<T>>	span(@NonNull java.util.function.Predicate<? super T> predicate)	Splits this Traversable into a prefix and remainder according to the given predicate.
Set<T>	tail()	Returns a new Traversable without its first element.
Option<? extends Set<T>>	tailOption()	Returns a new Traversable without its first element as an Option.
Set<T>	take(int n)	Returns the first n elements of this Traversable, or all elements if n exceeds the length.
Set<T>	takeRight(int n)	Returns the last n elements of this Traversable, or all elements if n exceeds the length.
Set<T>	takeUntil(@NonNull java.util.function.Predicate<? super T> predicate)	Takes elements from this Traversable until the given predicate holds for an element.
Set<T>	takeWhile(@NonNull java.util.function.Predicate<? super T> predicate)	Takes elements from this Traversable while the given predicate holds.
java.util.Set<T>	toJavaSet()	Converts this Vavr set to a java.util.Set, preserving insertion or sort order.
Set<T>	union(@NonNull Set<? extends T> that)	Returns a new set containing all distinct elements from this set and the given set.
<T1,T2> Tuple2<? extends Set<T1>,? extends Set<T2>>	unzip(@NonNull java.util.function.Function<? super T,Tuple2<? extends T1,? extends T2>> unzipper)	Unzips the elements of this Traversable by mapping each element to a pair and splitting them into two separate Traversable collections.
<T1,T2,T3> Tuple3<? extends Set<T1>,? extends Set<T2>,? extends Set<T3>>	unzip3(@NonNull java.util.function.Function<? super T,Tuple3<? extends T1,? extends T2,? extends T3>> unzipper)	Unzips the elements of this Traversable by mapping each element to a triple and splitting them into three separate Traversable collections.
<U> Set<Tuple2<T,U>>	zip(@NonNull java.lang.Iterable<? extends U> that)	Returns a Traversable formed by pairing elements of this Traversable with elements of another Iterable.
<U> Set<Tuple2<T,U>>	zipAll(@NonNull java.lang.Iterable<? extends U> that, T thisElem, U thatElem)	Returns a Traversable formed by pairing elements of this Traversable with elements of another Iterable, filling in placeholder elements when one collection is shorter than the other.
<U,R> Set<R>	zipWith(@NonNull java.lang.Iterable<? extends U> that, java.util.function.BiFunction<? super T,? super U,? extends R> mapper)	Returns a Traversable by combining elements of this Traversable with elements of another Iterable using a mapping function.
Set<Tuple2<T,java.lang.Integer>>	zipWithIndex()	Zips this Traversable with its indices, starting at 0.
<U> Set<U>	zipWithIndex(@NonNull java.util.function.BiFunction<? super T,? super java.lang.Integer,? extends U> mapper)	Zips this Traversable with its indices and maps the resulting pairs using the provided mapper.

Methods inherited from interface io.vavr.collection.Foldable

fold, reduce, reduceOption

Methods inherited from interface io.vavr.Function1

andThen, arity, compose, compose1, curried, isMemoized, memoized, partial, reversed, tupled

Methods inherited from interface io.vavr.collection.Traversable

arrangeBy, average, containsAll, count, equals, existsUnique, find, findLast, foldLeft, foldRight, forEachWithIndex, get, hasDefiniteSize, hashCode, head, headOption, isEmpty, isOrdered, isSequential, isSingleValued, isTraversableAgain, last, lastOption, max, maxBy, maxBy, min, minBy, minBy, mkCharSeq, mkCharSeq, mkCharSeq, mkString, mkString, mkString, nonEmpty, product, reduceLeft, reduceLeftOption, reduceRight, reduceRightOption, single, singleOption, size, spliterator, sum

Methods inherited from interface io.vavr.Value

collect, collect, corresponds, eq, exists, forAll, forEach, getOrElse, getOrElse, getOrElseThrow, getOrElseTry, getOrNull, isAsync, isLazy, out, out, stderr, stdout, stringPrefix, toArray, toCharSeq, toCompletableFuture, toEither, toEither, toInvalid, toInvalid, toJavaArray, toJavaArray, toJavaArray, toJavaCollection, toJavaList, toJavaList, toJavaMap, toJavaMap, toJavaMap, toJavaOptional, toJavaParallelStream, toJavaSet, toJavaStream, toLeft, toLeft, toLinkedMap, toLinkedMap, toLinkedSet, toList, toMap, toMap, toOption, toPriorityQueue, toPriorityQueue, toQueue, toRight, toRight, toSet, toSortedMap, toSortedMap, toSortedMap, toSortedMap, toSortedSet, toSortedSet, toStream, toString, toTree, toTree, toTry, toTry, toValid, toValid, toValidation, toValidation, toVector

Field Detail

serialVersionUID

static final long serialVersionUID

The serial version UID for serialization.

See Also:

Constant Field Values

Method Detail

narrow

static <T> Set<T> narrow(Set<? extends T> set)

Narrows a widened Set<? extends T> to Set<T> by performing a type-safe cast. This is eligible because immutable/read-only collections are covariant.

Type Parameters:

T - Component type of the Set.

Parameters:

set - A Set.

Returns:

the given set instance as narrowed type Set<T>.

add

Set<T> add(T element)

Returns a new set containing all elements of this set plus the given element, if it was not already present.

Parameters:

element - the element to add

Returns:

a new set including the element

addAll

Set<T> addAll(@NonNull java.lang.Iterable<? extends T> elements)

Returns a new set containing all elements of this set plus the given elements, excluding duplicates.

Parameters:

elements - the elements to add

Returns:

a new set including the additional elements

apply

@Deprecated
default java.lang.Boolean apply(T element)

Deprecated.

Will be removed

Tests if a given element is contained in this Set.

This method is equivalent to contains(Object).

Specified by:

apply in interface java.util.function.Function<T,java.lang.Boolean>

Specified by:

apply in interface Function1<T,java.lang.Boolean>

Parameters:

element - the element to test for membership.

Returns:

true if the given element is contained, false otherwise.

diff

Set<T> diff(@NonNull Set<? extends T> that)

Returns a new set containing all elements of this set except those in the given set.

Parameters:

that - the set of elements to remove

Returns:

a new set without the specified elements

intersect

Set<T> intersect(@NonNull Set<? extends T> that)

Returns a new set containing only the elements present in both this set and the given set.

Parameters:

that - the set to intersect with

Returns:

a new set with elements common to both sets

remove

Set<T> remove(T element)

Returns a new set with the given element removed, if it was present.

Parameters:

element - the element to remove

Returns:

a new set without the specified element

removeAll

Set<T> removeAll(@NonNull java.lang.Iterable<? extends T> elements)

Returns a new set with all given elements removed, if present.

Parameters:

elements - the elements to remove

Returns:

a new set without the specified elements

toJavaSet

java.util.Set<T> toJavaSet()

Converts this Vavr set to a java.util.Set, preserving insertion or sort order.

Specified by:

toJavaSet in interface Value<T>

Returns:

a new java.util.Set instance

union

Set<T> union(@NonNull Set<? extends T> that)

Returns a new set containing all distinct elements from this set and the given set.

Parameters:

that - the set to union with

Returns:

a new set with all elements from both sets

collect

<R> Set<R> collect(@NonNull PartialFunction<? super T,? extends R> partialFunction)

Description copied from interface: Traversable

Applies a PartialFunction to all elements that are defined for it and collects the results.

For each element in iteration order, the function is first tested:

 partialFunction.isDefinedAt(element)
 

If true, the element is mapped to type R:

 R newElement = partialFunction.apply(element)
 

Note: If this Traversable is ordered (i.e., extends Ordered), the caller must ensure that the resulting elements are comparable (i.e., implement Comparable).

Specified by:

collect in interface Traversable<T>

Type Parameters:

R - the type of elements in the resulting Traversable

Parameters:

partialFunction - a function that may not be defined for all elements of this traversable

Returns:

a new Traversable containing the results of applying the partial function

contains

boolean contains(T element)

Description copied from interface: Value

Shortcut for exists(e -> Objects.equals(e, element)), tests if the given element is contained.

Specified by:

contains in interface Value<T>

Parameters:

element - An Object of type A, may be null.

Returns:

true, if element is contained, false otherwise.

distinct

Set<T> distinct()

Description copied from interface: Traversable

Returns a new Traversable containing the elements of this instance with all duplicates removed. Element equality is determined using equals.

Specified by:

distinct in interface Traversable<T>

Returns:

a new Traversable without duplicate elements

distinctBy

Set<T> distinctBy(@NonNull java.util.Comparator<? super T> comparator)

Description copied from interface: Traversable

Returns a new Traversable containing the elements of this instance without duplicates, as determined by the given comparator.

Specified by:

distinctBy in interface Traversable<T>

Parameters:

comparator - a comparator used to determine equality of elements

Returns:

a new Traversable with duplicates removed

distinctBy

<U> Set<T> distinctBy(@NonNull java.util.function.Function<? super T,? extends U> keyExtractor)

Description copied from interface: Traversable

Returns a new Traversable containing the elements of this instance without duplicates, based on keys extracted from elements using keyExtractor.

The first occurrence of each key is retained in the resulting sequence.

Specified by:

distinctBy in interface Traversable<T>

Type Parameters:

U - the type of key

Parameters:

keyExtractor - a function to extract keys for determining uniqueness

Returns:

a new Traversable with duplicates removed based on keys

drop

Set<T> drop(int n)

Description copied from interface: Traversable

Returns a new Traversable without the first n elements, or an empty instance if this contains fewer than n elements.

Specified by:

drop in interface Traversable<T>

Parameters:

n - the number of elements to drop

Returns:

a new instance excluding the first n elements

dropRight

Set<T> dropRight(int n)

Description copied from interface: Traversable

Returns a new Traversable without the last n elements, or an empty instance if this contains fewer than n elements.

Specified by:

dropRight in interface Traversable<T>

Parameters:

n - the number of elements to drop from the end

Returns:

a new instance excluding the last n elements

dropUntil

Set<T> dropUntil(@NonNull java.util.function.Predicate<? super T> predicate)

Description copied from interface: Traversable

Returns a new Traversable starting from the first element that satisfies the given predicate, dropping all preceding elements.

Specified by:

dropUntil in interface Traversable<T>

Parameters:

predicate - a condition tested on each element

Returns:

a new instance starting from the first element matching the predicate

dropWhile

Set<T> dropWhile(@NonNull java.util.function.Predicate<? super T> predicate)

Description copied from interface: Traversable

Returns a new Traversable starting from the first element that does not satisfy the given predicate, dropping all preceding elements.

This is equivalent to dropUntil(predicate.negate()), which is useful for method references that cannot be negated directly.

Specified by:

dropWhile in interface Traversable<T>

Parameters:

predicate - a condition tested on each element

Returns:

a new instance starting from the first element not matching the predicate

filter

Set<T> filter(@NonNull java.util.function.Predicate<? super T> predicate)

Description copied from interface: Traversable

Returns a new traversable containing only the elements that satisfy the given predicate.

Specified by:

filter in interface Traversable<T>

Parameters:

predicate - the condition to test elements

Returns:

a traversable with elements matching the predicate

reject

Set<T> reject(@NonNull java.util.function.Predicate<? super T> predicate)

Description copied from interface: Traversable

Returns a new traversable containing only the elements that do not satisfy the given predicate.

This is equivalent to filter(predicate.negate()).

Specified by:

reject in interface Traversable<T>

Parameters:

predicate - the condition to test elements

Returns:

a traversable with elements not matching the predicate

flatMap

<U> Set<U> flatMap(@NonNull java.util.function.Function<? super T,? extends java.lang.Iterable<? extends U>> mapper)

Description copied from interface: Traversable

Transforms each element of this Traversable into an Iterable of elements and flattens the resulting iterables into a single Traversable.

Specified by:

flatMap in interface Traversable<T>

Type Parameters:

U - the type of elements in the resulting Traversable

Parameters:

mapper - a function mapping elements to iterables

Returns:

a new Traversable containing all elements produced by applying mapper and flattening

groupBy

<C> Map<C,? extends Set<T>> groupBy(@NonNull java.util.function.Function<? super T,? extends C> classifier)

Description copied from interface: Traversable

Groups elements of this Traversable based on a classifier function.

Specified by:

groupBy in interface Traversable<T>

Type Parameters:

C - The type of the group keys

Parameters:

classifier - A function that assigns each element to a group

Returns:

A map where each key corresponds to a group of elements

See Also:

Traversable.arrangeBy(Function)

grouped

Iterator<? extends Set<T>> grouped(int size)

Description copied from interface: Traversable

Splits this Traversable into consecutive blocks of the given size.

Let length be the number of elements in this Traversable:

• If empty, the resulting Iterator is empty.
• If size <= length, the resulting Iterator contains length / size blocks of size size and possibly a final smaller block of size length % size.
• If size > length, the resulting Iterator contains a single block of size length.

Examples:

 
 [].grouped(1) = []
 [].grouped(0) throws
 [].grouped(-1) throws
 [1,2,3,4].grouped(2) = [[1,2],[3,4]]
 [1,2,3,4,5].grouped(2) = [[1,2],[3,4],[5]]
 [1,2,3,4].grouped(5) = [[1,2,3,4]]
 
 

Note: grouped(size) is equivalent to sliding(size, size).

Specified by:

grouped in interface Traversable<T>

Parameters:

size - the block size; must be positive

Returns:

an Iterator over blocks of elements

init

Set<T> init()

Description copied from interface: Traversable

Returns all elements of this Traversable except the last one.

This is the dual of Traversable.tail().

Specified by:

init in interface Traversable<T>

Returns:

a new instance containing all elements except the last

initOption

Option<? extends Set<T>> initOption()

Description copied from interface: Traversable

Returns all elements of this Traversable except the last one, wrapped in an Option.

This is the dual of Traversable.tailOption().

Specified by:

initOption in interface Traversable<T>

Returns:

Some(traversable) if non-empty, or None if this Traversable is empty

isDistinct

default boolean isDistinct()

Description copied from interface: Traversable

Indicates whether this Traversable may contain only distinct elements.

Specified by:

isDistinct in interface Traversable<T>

Returns:

true if this Traversable may contain only distinct elements, false otherwise

iterator

@NonNull Iterator<T> iterator()

Description copied from interface: Traversable

Returns an iterator over the elements of this Traversable, implemented via Traversable.head() and Traversable.tail(). Subclasses may override for a more efficient implementation.

Specified by:

iterator in interface java.lang.Iterable<T>

Specified by:

iterator in interface Traversable<T>

Specified by:

iterator in interface Value<T>

Returns:

a new Iterator over the elements of this Traversable

length

int length()

Description copied from interface: Traversable

Returns the number of elements in this Traversable.

Equivalent to Traversable.size().

Specified by:

length in interface Traversable<T>

Returns:

the number of elements

map

<U> Set<U> map(@NonNull java.util.function.Function<? super T,? extends U> mapper)

Description copied from interface: Traversable

Transforms the elements of this Traversable to a new type, preserving order if defined.

Specified by:

map in interface Traversable<T>

Specified by:

map in interface Value<T>

Type Parameters:

U - the target element type

Parameters:

mapper - a mapping function

Returns:

a new Traversable containing the mapped elements

mapTo

default <U> Set<U> mapTo(U value)

Description copied from interface: Value

Maps the underlying value to another fixed value.

Specified by:

mapTo in interface Traversable<T>

Specified by:

mapTo in interface Value<T>

Type Parameters:

U - The new component type

Parameters:

value - value to replace the contents with

Returns:

A new value

mapToVoid

default Set<java.lang.Void> mapToVoid()

Description copied from interface: Value

Maps the underlying value to Void

Specified by:

mapToVoid in interface Traversable<T>

Specified by:

mapToVoid in interface Value<T>

Returns:

A new value of type Void

orElse

Set<T> orElse(@NonNull java.lang.Iterable<? extends T> other)

Description copied from interface: Traversable

Returns this Traversable if it is non-empty; otherwise, returns the given alternative.

Specified by:

orElse in interface Traversable<T>

Parameters:

other - an alternative Traversable to return if this is empty

Returns:

this Traversable if non-empty, otherwise other

orElse

Set<T> orElse(@NonNull java.util.function.Supplier<? extends java.lang.Iterable<? extends T>> supplier)

Description copied from interface: Traversable

Returns this Traversable if it is non-empty; otherwise, returns the result of evaluating the given supplier.

Specified by:

orElse in interface Traversable<T>

Parameters:

supplier - a supplier of an alternative Traversable if this is empty

Returns:

this Traversable if non-empty, otherwise the result of supplier.get()

partition

Tuple2<? extends Set<T>,? extends Set<T>> partition(@NonNull java.util.function.Predicate<? super T> predicate)

Description copied from interface: Traversable

Splits this Traversable into two partitions according to a predicate.

The first partition contains all elements that satisfy the predicate, and the second contains all elements that do not. The original iteration order is preserved.

Specified by:

partition in interface Traversable<T>

Parameters:

predicate - a predicate used to classify elements

Returns:

a Tuple2 containing the two resulting Traversable instances

peek

Set<T> peek(@NonNull java.util.function.Consumer<? super T> action)

Description copied from interface: Value

Performs the given action on the first element if this is an eager implementation. Performs the given action on all elements (the first immediately, successive deferred), if this is a lazy implementation.

Specified by:

peek in interface Traversable<T>

Specified by:

peek in interface Value<T>

Parameters:

action - The action that will be performed on the element(s).

Returns:

this instance

replace

Set<T> replace(T currentElement,
               T newElement)

Description copied from interface: Traversable

Replaces the first occurrence of currentElement with newElement, if it exists.

Specified by:

replace in interface Traversable<T>

Parameters:

currentElement - the element to be replaced

newElement - the replacement element

Returns:

a new Traversable with the first occurrence of currentElement replaced by newElement

replaceAll

Set<T> replaceAll(T currentElement,
                  T newElement)

Description copied from interface: Traversable

Replaces all occurrences of currentElement with newElement.

Specified by:

replaceAll in interface Traversable<T>

Parameters:

currentElement - the element to be replaced

newElement - the replacement element

Returns:

a new Traversable with all occurrences of currentElement replaced by newElement

retainAll

Set<T> retainAll(@NonNull java.lang.Iterable<? extends T> elements)

Description copied from interface: Traversable

Retains only the elements from this Traversable that are contained in the given elements.

Specified by:

retainAll in interface Traversable<T>

Parameters:

elements - the elements to keep

Returns:

a new Traversable containing only the elements present in elements, in their original order

scan

Set<T> scan(T zero,
            @NonNull java.util.function.BiFunction<? super T,? super T,? extends T> operation)

Description copied from interface: Traversable

Computes a prefix scan of the elements of this Traversable.

The neutral element zero may be applied more than once.

Specified by:

scan in interface Traversable<T>

Parameters:

zero - the neutral element for the operator

operation - an associative binary operator

Returns:

a new Traversable containing the prefix scan of the elements

scanLeft

<U> Set<U> scanLeft(U zero,
                    @NonNull java.util.function.BiFunction<? super U,? super T,? extends U> operation)

Description copied from interface: Traversable

Produces a collection containing cumulative results of applying the operator from left to right.

Will not terminate for infinite collections. The results may vary across runs unless the collection is ordered.

Specified by:

scanLeft in interface Traversable<T>

Type Parameters:

U - the type of the resulting elements

Parameters:

zero - the initial value

operation - a binary operator applied to the intermediate result and each element

Returns:

a new Traversable containing the cumulative results

scanRight

<U> Set<U> scanRight(U zero,
                     @NonNull java.util.function.BiFunction<? super T,? super U,? extends U> operation)

Description copied from interface: Traversable

Produces a collection containing cumulative results of applying the operator from right to left.

The head of the resulting collection is the last cumulative result. Will not terminate for infinite collections. Results may vary across runs unless the collection is ordered.

Specified by:

scanRight in interface Traversable<T>

Type Parameters:

U - the type of the resulting elements

Parameters:

zero - the initial value

operation - a binary operator applied to each element and the intermediate result

Returns:

a new Traversable containing the cumulative results

slideBy

Iterator<? extends Set<T>> slideBy(@NonNull java.util.function.Function<? super T,?> classifier)

Description copied from interface: Traversable

Partitions this Traversable into consecutive non-overlapping windows according to a classification function.

Each window contains elements with the same class, as determined by classifier. Two consecutive elements belong to the same window only if classifier returns equal values for both. Otherwise, the current window ends and a new window begins with the next element.

Examples:

 [].slideBy(Function.identity()) = []
 [1,2,3,4,4,5].slideBy(Function.identity()) = [[1],[2],[3],[4,4],[5]]
 [1,2,3,10,12,5,7,20,29].slideBy(x -> x / 10) = [[1,2,3],[10,12],[5,7],[20,29]]
 

Specified by:

slideBy in interface Traversable<T>

Parameters:

classifier - A function classifying elements into groups

Returns:

An Iterator of windows (grouped elements)

sliding

Iterator<? extends Set<T>> sliding(int size)

Description copied from interface: Traversable

Slides a window of a given size over this Traversable with a step size of 1.

This is equivalent to calling Traversable.sliding(int, int) with a step size of 1.

Specified by:

sliding in interface Traversable<T>

Parameters:

size - a positive window size

Returns:

An Iterator of windows, each containing up to size elements

sliding

Iterator<? extends Set<T>> sliding(int size,
                                   int step)

Description copied from interface: Traversable

Slides a window of a specific size with a given step over this Traversable.

Examples:

 [].sliding(1, 1) = []
 [1,2,3,4,5].sliding(2, 3) = [[1,2],[4,5]]
 [1,2,3,4,5].sliding(2, 4) = [[1,2],[5]]
 [1,2,3,4,5].sliding(2, 5) = [[1,2]]
 [1,2,3,4].sliding(5, 3) = [[1,2,3,4],[4]]
 

Specified by:

sliding in interface Traversable<T>

Parameters:

size - a positive window size

step - a positive step size

Returns:

an Iterator of windows with the given size and step

span

Tuple2<? extends Set<T>,? extends Set<T>> span(@NonNull java.util.function.Predicate<? super T> predicate)

Description copied from interface: Traversable

Splits this Traversable into a prefix and remainder according to the given predicate.

The first element of the returned Tuple is the longest prefix of elements satisfying predicate, and the second element is the remaining elements.

Specified by:

span in interface Traversable<T>

Parameters:

predicate - a predicate used to determine the prefix

Returns:

a Tuple containing the prefix and remainder

tail

Set<T> tail()

Description copied from interface: Traversable

Returns a new Traversable without its first element.

Specified by:

tail in interface Traversable<T>

Returns:

a new Traversable containing all elements except the first

tailOption

Option<? extends Set<T>> tailOption()

Description copied from interface: Traversable

Returns a new Traversable without its first element as an Option.

Specified by:

tailOption in interface Traversable<T>

Returns:

Some(traversable) if non-empty, otherwise None

take

Set<T> take(int n)

Description copied from interface: Traversable

Returns the first n elements of this Traversable, or all elements if n exceeds the length.

Equivalent to sublist(0, max(0, min(length(), n))), but safe for n < 0 or n > length().

If n < 0, an empty instance is returned. If n > length(), the full instance is returned.

Specified by:

take in interface Traversable<T>

Parameters:

n - the number of elements to take

Returns:

a new Traversable containing the first n elements

takeRight

Set<T> takeRight(int n)

Description copied from interface: Traversable

Returns the last n elements of this Traversable, or all elements if n exceeds the length.

Equivalent to sublist(max(0, length() - n), length()), but safe for n < 0 or n > length().

If n < 0, an empty instance is returned. If n > length(), the full instance is returned.

Specified by:

takeRight in interface Traversable<T>

Parameters:

n - the number of elements to take from the end

Returns:

a new Traversable containing the last n elements

takeUntil

Set<T> takeUntil(@NonNull java.util.function.Predicate<? super T> predicate)

Description copied from interface: Traversable

Takes elements from this Traversable until the given predicate holds for an element.

Equivalent to takeWhile(predicate.negate()), but useful when using method references that cannot be negated directly.

Specified by:

takeUntil in interface Traversable<T>

Parameters:

predicate - a condition tested sequentially on the elements

Returns:

a new Traversable containing all elements before the first one that satisfies the predicate

takeWhile

Set<T> takeWhile(@NonNull java.util.function.Predicate<? super T> predicate)

Description copied from interface: Traversable

Takes elements from this Traversable while the given predicate holds.

Specified by:

takeWhile in interface Traversable<T>

Parameters:

predicate - a condition tested sequentially on the elements

Returns:

a new Traversable containing all elements up to (but not including) the first one that does not satisfy the predicate

unzip

<T1,T2> Tuple2<? extends Set<T1>,? extends Set<T2>> unzip(@NonNull java.util.function.Function<? super T,Tuple2<? extends T1,? extends T2>> unzipper)

Description copied from interface: Traversable

Unzips the elements of this Traversable by mapping each element to a pair and splitting them into two separate Traversable collections.

Specified by:

unzip in interface Traversable<T>

Type Parameters:

T1 - type of the first element in the resulting pairs

T2 - type of the second element in the resulting pairs

Parameters:

unzipper - a function that maps elements of this Traversable to pairs

Returns:

a Tuple2 containing two Traversable collections with the split elements

unzip3

<T1,T2,T3> Tuple3<? extends Set<T1>,? extends Set<T2>,? extends Set<T3>> unzip3(@NonNull java.util.function.Function<? super T,Tuple3<? extends T1,? extends T2,? extends T3>> unzipper)

Description copied from interface: Traversable

Unzips the elements of this Traversable by mapping each element to a triple and splitting them into three separate Traversable collections.

Specified by:

unzip3 in interface Traversable<T>

Type Parameters:

T1 - type of the first element in the resulting triples

T2 - type of the second element in the resulting triples

T3 - type of the third element in the resulting triples

Parameters:

unzipper - a function that maps elements of this Traversable to triples

Returns:

a Tuple3 containing three Traversable collections with the split elements

zip

<U> Set<Tuple2<T,U>> zip(@NonNull java.lang.Iterable<? extends U> that)

Description copied from interface: Traversable

Returns a Traversable formed by pairing elements of this Traversable with elements of another Iterable. Pairing stops when either collection runs out of elements; any remaining elements in the longer collection are ignored.

The length of the resulting Traversable is the minimum of the lengths of this Traversable and that.

Specified by:

zip in interface Traversable<T>

Type Parameters:

U - the type of elements in the second half of each pair

Parameters:

that - an Iterable providing the second element of each pair

Returns:

a new Traversable containing pairs of corresponding elements

zipWith

<U,R> Set<R> zipWith(@NonNull java.lang.Iterable<? extends U> that,
                           java.util.function.BiFunction<? super T,? super U,? extends R> mapper)

Description copied from interface: Traversable

Returns a Traversable by combining elements of this Traversable with elements of another Iterable using a mapping function. Pairing stops when either collection runs out of elements.

The length of the resulting Traversable is the minimum of the lengths of this Traversable and that.

Specified by:

zipWith in interface Traversable<T>

Type Parameters:

U - the type of elements in the second parameter of the mapper

R - the type of elements in the resulting Traversable

Parameters:

that - an Iterable providing the second parameter of the mapper

mapper - a function that combines elements from this and that into a new element

Returns:

a new Traversable containing mapped elements

zipAll

<U> Set<Tuple2<T,U>> zipAll(@NonNull java.lang.Iterable<? extends U> that,
                                  T thisElem,
                                  U thatElem)

Description copied from interface: Traversable

Returns a Traversable formed by pairing elements of this Traversable with elements of another Iterable, filling in placeholder elements when one collection is shorter than the other.

The length of the resulting Traversable is the maximum of the lengths of this Traversable and that.

If this Traversable is shorter than that, thisElem is used as a filler. Conversely, if that is shorter, thatElem is used.

Specified by:

zipAll in interface Traversable<T>

Type Parameters:

U - the type of elements in the second half of each pair

Parameters:

that - an Iterable providing the second element of each pair

thisElem - the element used to fill missing values if this Traversable is shorter than that

thatElem - the element used to fill missing values if that is shorter than this Traversable

Returns:

a new Traversable containing pairs of elements, including fillers as needed

zipWithIndex

Set<Tuple2<T,java.lang.Integer>> zipWithIndex()

Description copied from interface: Traversable

Zips this Traversable with its indices, starting at 0.

Specified by:

zipWithIndex in interface Traversable<T>

Returns:

a new Traversable containing each element paired with its index

zipWithIndex

<U> Set<U> zipWithIndex(@NonNull java.util.function.BiFunction<? super T,? super java.lang.Integer,? extends U> mapper)

Description copied from interface: Traversable

Zips this Traversable with its indices and maps the resulting pairs using the provided mapper.

Specified by:

zipWithIndex in interface Traversable<T>

Type Parameters:

U - the type of elements in the resulting Traversable

Parameters:

mapper - a function mapping an element and its index to a new element

Returns:

a new Traversable containing the mapped elements