HashSet (vavr-champ 0.10.5 API)

java.lang.Object
- io.vavr.collection.HashSet<T>

Type Parameters:

T - the element type

All Implemented Interfaces:

Foldable<T>, Set<T>, Traversable<T>, Value<T>, java.io.Serializable, java.lang.Iterable<T>
```
public final class HashSet<T>
extends java.lang.Object
implements Set<T>, java.io.Serializable
```
Implements an immutable set using a Compressed Hash-Array Mapped Prefix-tree (CHAMP).
Features:
- supports up to 2³⁰ entries
- allows null elements
- is immutable
- is thread-safe
- does not guarantee a specific iteration order
Performance characteristics:
- add: O(1)
- remove: O(1)
- contains: O(1)
- toMutable: O(1) + O(log N) distributed across subsequent updates in the mutable copy
- clone: O(1)
- iterator.next(): O(1)
Implementation details:
This set performs read and write operations of single elements in O(1) time, and in O(1) space.
The CHAMP trie contains nodes that may be shared with other sets.
If a write operation is performed on a node, then this set creates a copy of the node and of all parent nodes up to the root (copy-path-on-write). Since the CHAMP trie has a fixed maximal height, the cost is O(1).
The immutable version of this set extends from the non-public class ChampBitmapIndexNode. This design safes 16 bytes for every instance, and reduces the number of redirections for finding an element in the collection by 1.
References:
Portions of the code in this class have been derived from 'The Capsule Hash Trie Collections Library', and from 'JHotDraw 8'.

Michael J. Steindorfer (2017). Efficient Immutable Collections.

michael.steindorfer.name

The Capsule Hash Trie Collections Library.
Copyright (c) Michael Steindorfer. BSD-2-Clause License

github.com

JHotDraw 8. Copyright © 2023 The authors and contributors of JHotDraw. MIT License.

github.com
See Also:

Serialized Form

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`HashSet<T>`	`add(T element)` Add the given element to this set, if it is not already contained.
`HashSet<T>`	`addAll(java.lang.Iterable<? extends T> elements)` Adds all of the given elements to this set, if not already contained.
`<R> HashSet<R>`	`collect(PartialFunction<? super T,? extends R> partialFunction)` Collects all elements that are in the domain of the given `partialFunction` by mapping the elements to type `R`.
`static <T> java.util.stream.Collector<T,java.util.ArrayList<T>,HashSet<T>>`	`collector()` Returns a `Collector` which may be used in conjunction with `Stream.collect(java.util.stream.Collector)` to obtain a `HashSet`.
`boolean`	`contains(T element)` Shortcut for `exists(e -> Objects.equals(e, element))`, tests if the given `element` is contained.
`HashSet<T>`	`diff(Set<? extends T> elements)` Calculates the difference between this set and another set.
`HashSet<T>`	`distinct()` Returns a new version of this which contains no duplicates.
`HashSet<T>`	`distinctBy(java.util.Comparator<? super T> comparator)` Returns a new version of this which contains no duplicates.
`<U> HashSet<T>`	`distinctBy(java.util.function.Function<? super T,? extends U> keyExtractor)` Returns a new version of this which contains no duplicates.
`HashSet<T>`	`drop(int n)` Drops the first n elements of this or all elements, if this length < n.
`HashSet<T>`	`dropRight(int n)` Drops the last n elements of this or all elements, if this length < n.
`HashSet<T>`	`dropUntil(java.util.function.Predicate<? super T> predicate)` Drops elements until the predicate holds for the current element.
`HashSet<T>`	`dropWhile(java.util.function.Predicate<? super T> predicate)` Drops elements while the predicate holds for the current element.
`static <T> HashSet<T>`	`empty()`
`boolean`	`equals(java.lang.Object o)` In Vavr there are four basic classes of collections: Seq (sequential elements) Set (distinct elements) Map (indexed elements) Multimap (indexed collections) Two collection instances of these classes are equal if and only if both collections belong to the same basic collection class (Seq, Set, Map or Multimap) contain the same elements have the same element order, if the collections are of type Seq Two Map/Multimap elements, resp.
`static <T> HashSet<T>`	`fill(int n, java.util.function.Supplier<? extends T> s)` Returns a HashSet containing tuples returned by `n` calls to a given Supplier `s`.
`HashSet<T>`	`filter(java.util.function.Predicate<? super T> predicate)` Returns a new traversable consisting of all elements which satisfy the given predicate.
`HashSet<T>`	`filterNot(java.util.function.Predicate<? super T> predicate)` Returns a new traversable consisting of all elements which do not satisfy the given predicate.
`<U> HashSet<U>`	`flatMap(java.util.function.Function<? super T,? extends java.lang.Iterable<? extends U>> mapper)` FlatMaps this Traversable.
`<U> U`	`foldRight(U zero, java.util.function.BiFunction<? super T,? super U,? extends U> f)` Folds this elements from the right, starting with `zero` and successively calling `combine`.
`<C> Map<C,HashSet<T>>`	`groupBy(java.util.function.Function<? super T,? extends C> classifier)` Groups this elements by classifying the elements.
`Iterator<HashSet<T>>`	`grouped(int size)` Groups this `Traversable` into fixed size blocks.
`boolean`	`hasDefiniteSize()` Checks if this Traversable is known to have a finite size.
`int`	`hashCode()` Returns the hash code of this collection.
`T`	`head()` Returns the first element of a non-empty Traversable.
`Option<T>`	`headOption()` Returns the first element of a non-empty Traversable as `Option`.
`HashSet<T>`	`init()` Dual of Traversable.tail(), returning all elements except the last.
`Option<HashSet<T>>`	`initOption()` Dual of Traversable.tailOption(), returning all elements except the last as `Option`.
`HashSet<T>`	`intersect(Set<? extends T> elements)` Computes the intersection between this set and another set.
`boolean`	`isAsync()` A `HashSet` is computed synchronously.
`boolean`	`isEmpty()` Checks if this Traversable is empty.
`boolean`	`isLazy()` A `HashSet` is computed eagerly.
`boolean`	`isTraversableAgain()` Checks if this Traversable can be repeatedly traversed.
`Iterator<T>`	`iterator()` An iterator by means of head() and tail().
`T`	`last()` Dual of Traversable.head(), returning the last element.
`int`	`length()` Computes the number of elements of this Traversable.
`<U> HashSet<U>`	`map(java.util.function.Function<? super T,? extends U> mapper)` Maps the elements of this `Traversable` to elements of a new type preserving their order, if any.
`java.lang.String`	`mkString(java.lang.CharSequence prefix, java.lang.CharSequence delimiter, java.lang.CharSequence suffix)` Joins the string representations of this elements using a specific delimiter, prefix and suffix.
`static <T> HashSet<T>`	`narrow(HashSet<? extends T> hashSet)` Narrows a widened `HashSet<? extends T>` to `HashSet<T>` by performing a type-safe cast.
`static <T> HashSet<T>`	`of(T... elements)` Creates a HashSet of the given elements.
`static <T> HashSet<T>`	`of(T element)` Returns a singleton `HashSet`, i.e.
`static HashSet<java.lang.Boolean>`	`ofAll(boolean... elements)` Creates a HashSet from boolean values.
`static HashSet<java.lang.Byte>`	`ofAll(byte... elements)` Creates a HashSet from byte values.
`static HashSet<java.lang.Character>`	`ofAll(char... elements)` Creates a HashSet from char values.
`static HashSet<java.lang.Double>`	`ofAll(double... elements)` Creates a HashSet from double values.
`static HashSet<java.lang.Float>`	`ofAll(float... elements)` Creates a HashSet from float values.
`static HashSet<java.lang.Integer>`	`ofAll(int... elements)` Creates a HashSet from int values.
`static <T> HashSet<T>`	`ofAll(java.lang.Iterable<? extends T> elements)` Creates a HashSet of the given elements.
`static HashSet<java.lang.Long>`	`ofAll(long... elements)` Creates a HashSet from long values.
`static HashSet<java.lang.Short>`	`ofAll(short... elements)` Creates a HashSet from short values.
`static <T> HashSet<T>`	`ofAll(java.util.stream.Stream<? extends T> javaStream)` Creates a HashSet that contains the elements of the given `Stream`.
`HashSet<T>`	`orElse(java.lang.Iterable<? extends T> other)` Returns this `Traversable` if it is nonempty, otherwise return the alternative.
`HashSet<T>`	`orElse(java.util.function.Supplier<? extends java.lang.Iterable<? extends T>> supplier)` Returns this `Traversable` if it is nonempty, otherwise return the result of evaluating supplier.
`Tuple2<HashSet<T>,HashSet<T>>`	`partition(java.util.function.Predicate<? super T> predicate)` Creates a partition of this `Traversable` by splitting this elements in two in distinct traversables according to a predicate.
`HashSet<T>`	`peek(java.util.function.Consumer<? super T> action)` Performs the given `action` on the first element if this is an eager implementation.
`static HashSet<java.lang.Character>`	`range(char from, char toExclusive)`
`static HashSet<java.lang.Integer>`	`range(int from, int toExclusive)` Creates a HashSet of int numbers starting from `from`, extending to `toExclusive - 1`.
`static HashSet<java.lang.Long>`	`range(long from, long toExclusive)` Creates a HashSet of long numbers starting from `from`, extending to `toExclusive - 1`.
`static HashSet<java.lang.Character>`	`rangeBy(char from, char toExclusive, int step)`
`static HashSet<java.lang.Double>`	`rangeBy(double from, double toExclusive, double step)`
`static HashSet<java.lang.Integer>`	`rangeBy(int from, int toExclusive, int step)` Creates a HashSet of int numbers starting from `from`, extending to `toExclusive - 1`, with `step`.
`static HashSet<java.lang.Long>`	`rangeBy(long from, long toExclusive, long step)` Creates a HashSet of long numbers starting from `from`, extending to `toExclusive - 1`, with `step`.
`static HashSet<java.lang.Character>`	`rangeClosed(char from, char toInclusive)`
`static HashSet<java.lang.Integer>`	`rangeClosed(int from, int toInclusive)` Creates a HashSet of int numbers starting from `from`, extending to `toInclusive`.
`static HashSet<java.lang.Long>`	`rangeClosed(long from, long toInclusive)` Creates a HashSet of long numbers starting from `from`, extending to `toInclusive`.
`static HashSet<java.lang.Character>`	`rangeClosedBy(char from, char toInclusive, int step)`
`static HashSet<java.lang.Double>`	`rangeClosedBy(double from, double toInclusive, double step)`
`static HashSet<java.lang.Integer>`	`rangeClosedBy(int from, int toInclusive, int step)` Creates a HashSet of int numbers starting from `from`, extending to `toInclusive`, with `step`.
`static HashSet<java.lang.Long>`	`rangeClosedBy(long from, long toInclusive, long step)` Creates a HashSet of long numbers starting from `from`, extending to `toInclusive`, with `step`.
`HashSet<T>`	`remove(T key)` Removes a specific element from this set, if present.
`HashSet<T>`	`removeAll(java.lang.Iterable<? extends T> elements)` Removes all of the given elements from this set, if present.
`HashSet<T>`	`replace(T currentElement, T newElement)` Replaces the first occurrence (if exists) of the given currentElement with newElement.
`HashSet<T>`	`replaceAll(T currentElement, T newElement)` Replaces all occurrences of the given currentElement with newElement.
`HashSet<T>`	`retainAll(java.lang.Iterable<? extends T> elements)` Keeps all occurrences of the given elements from this.
`HashSet<T>`	`scan(T zero, java.util.function.BiFunction<? super T,? super T,? extends T> operation)` Computes a prefix scan of the elements of the collection.
`<U> HashSet<U>`	`scanLeft(U zero, java.util.function.BiFunction<? super U,? super T,? extends U> operation)` Produces a collection containing cumulative results of applying the operator going left to right.
`<U> HashSet<U>`	`scanRight(U zero, java.util.function.BiFunction<? super T,? super U,? extends U> operation)` Produces a collection containing cumulative results of applying the operator going right to left.
`Iterator<HashSet<T>>`	`slideBy(java.util.function.Function<? super T,?> classifier)` Slides a non-overlapping window of a variable size over this `Traversable`.
`Iterator<HashSet<T>>`	`sliding(int size)` Slides a window of a specific `size` and step size 1 over this `Traversable` by calling `Traversable.sliding(int, int)`.
`Iterator<HashSet<T>>`	`sliding(int size, int step)` Slides a window of a specific `size` and `step` size over this `Traversable`.
`Tuple2<HashSet<T>,HashSet<T>>`	`span(java.util.function.Predicate<? super T> predicate)` Returns a tuple where the first element is the longest prefix of elements that satisfy the given `predicate` and the second element is the remainder.
`java.util.Spliterator<T>`	`spliterator()`
`java.lang.String`	`stringPrefix()` Returns the name of this Value type, which is used by toString().
`static <T> HashSet<T>`	`tabulate(int n, java.util.function.Function<? super java.lang.Integer,? extends T> f)` Returns an HashSet containing `n` values of a given Function `f` over a range of integer values from 0 to `n - 1`.
`HashSet<T>`	`tail()` Drops the first element of a non-empty Traversable.
`Option<HashSet<T>>`	`tailOption()` Drops the first element of a non-empty Traversable and returns an `Option`.
`HashSet<T>`	`take(int n)` Takes the first n elements of this or all elements, if this length < n.
`HashSet<T>`	`takeRight(int n)` Takes the last n elements of this or all elements, if this length < n.
`HashSet<T>`	`takeUntil(java.util.function.Predicate<? super T> predicate)` Takes elements until the predicate holds for the current element.
`HashSet<T>`	`takeWhile(java.util.function.Predicate<? super T> predicate)` Takes elements while the predicate holds for the current element.
`java.util.HashSet<T>`	`toJavaSet()` Converts this Vavr `Set` to a `java.util.Set` while preserving characteristics like insertion order (`LinkedHashSet`) and sort order (`SortedSet`).
`java.lang.String`	`toString()` Clarifies that values have a proper toString() method implemented.
`<U> U`	`transform(java.util.function.Function<? super HashSet<T>,? extends U> f)` Transforms this `HashSet`.
`HashSet<T>`	`union(Set<? extends T> elements)` Adds all of the elements of `that` set to this set, if not already present.
`<U> HashSet<Tuple2<T,U>>`	`zip(java.lang.Iterable<? extends U> that)` Returns a traversable formed from this traversable and another Iterable collection by combining corresponding elements in pairs.
`<U> HashSet<Tuple2<T,U>>`	`zipAll(java.lang.Iterable<? extends U> that, T thisElem, U thatElem)` Returns a traversable formed from this traversable and another Iterable by combining corresponding elements in pairs.
`<U,R> HashSet<R>`	`zipWith(java.lang.Iterable<? extends U> that, java.util.function.BiFunction<? super T,? super U,? extends R> mapper)` Returns a traversable formed from this traversable and another Iterable collection by mapping elements.
`HashSet<Tuple2<T,java.lang.Integer>>`	`zipWithIndex()` Zips this traversable with its indices.
`<U> HashSet<U>`	`zipWithIndex(java.util.function.BiFunction<? super T,? super java.lang.Integer,? extends U> mapper)` Zips this traversable with its indices by applying mapper provided.

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface io.vavr.collection.Set
isDistinct, narrow

Methods inherited from interface io.vavr.collection.Traversable
arrangeBy, average, containsAll, count, existsUnique, find, findLast, fold, foldLeft, forEachWithIndex, get, isOrdered, isSequential, isSingleValued, lastOption, max, maxBy, maxBy, min, minBy, minBy, mkCharSeq, mkCharSeq, mkCharSeq, mkString, mkString, narrow, nonEmpty, product, reduce, reduceLeft, reduceLeftOption, reduceOption, reduceRight, reduceRightOption, single, singleOption, size, sum, toLinkedMap, toMap, toSortedMap, toSortedMap, unzip, unzip3

Methods inherited from interface io.vavr.Value
collect, collect, corresponds, eq, exists, forAll, forEach, getOrElse, getOrElse, getOrElseThrow, getOrElseTry, getOrNull, narrow, out, out, stderr, stdout, 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, toTree, toTree, toTry, toTry, toValid, toValid, toValidation, toValidation, toVector

- Method Detail
 - empty
```
public static <T> HashSet<T> empty()
```
 - collector
```
public static <T> java.util.stream.Collector<T,java.util.ArrayList<T>,HashSet<T>> collector()
```
 Returns a Collector which may be used in conjunction with Stream.collect(java.util.stream.Collector) to obtain a HashSet.
 
 Type Parameters:
 
 T - Component type of the HashSet.
 
 Returns:
 
 A io.vavr.collection.HashSet Collector.
 - narrow
```
public static <T> HashSet<T> narrow(HashSet<? extends T> hashSet)
```
 Narrows a widened HashSet<? extends T> to HashSet<T> by performing a type-safe cast. This is eligible because immutable/read-only collections are covariant.
 
 Type Parameters:
 
 T - Component type of the HashSet.
 
 Parameters:
 
 hashSet - A HashSet.
 
 Returns:
 
 the given hashSet instance as narrowed type HashSet<T>.
 - of
```
public static <T> HashSet<T> of(T element)
```
 Returns a singleton HashSet, i.e. a HashSet of one element.
 
 Type Parameters:
 
 T - The component type
 
 Parameters:
 
 element - An element.
 
 Returns:
 
 A new HashSet instance containing the given element
 - of
```
@SafeVarargs
public static <T> HashSet<T> of(T... elements)
```
 Creates a HashSet of the given elements.
```
HashSet.of(1, 2, 3, 4)
```
 Type Parameters:
 
 T - Component type of the HashSet.
 
 Parameters:
 
 elements - Zero or more elements.
 
 Returns:
 
 A set containing the given elements.
 
 Throws:
 
 java.lang.NullPointerException - if elements is null
 - tabulate
```
public static <T> HashSet<T> tabulate(int n,
 java.util.function.Function<? super java.lang.Integer,? extends T> f)
```
 Returns an HashSet containing n values of a given Function f over a range of integer values from 0 to n - 1.
 
 Type Parameters:
 
 T - Component type of the HashSet
 
 Parameters:
 
 n - The number of elements in the HashSet
 
 f - The Function computing element values
 
 Returns:
 
 An HashSet consisting of elements f(0),f(1), ..., f(n - 1)
 
 Throws:
 
 java.lang.NullPointerException - if f is null
 - fill
```
public static <T> HashSet<T> fill(int n,
 java.util.function.Supplier<? extends T> s)
```
 Returns a HashSet containing tuples returned by n calls to a given Supplier s.
 
 Type Parameters:
 
 T - Component type of the HashSet
 
 Parameters:
 
 n - The number of elements in the HashSet
 
 s - The Supplier computing element values
 
 Returns:
 
 An HashSet of size n, where each element contains the result supplied by s.
 
 Throws:
 
 java.lang.NullPointerException - if s is null
 - ofAll
```
public static <T> HashSet<T> ofAll(java.lang.Iterable<? extends T> elements)
```
 Creates a HashSet of the given elements.
 
 Type Parameters:
 
 T - The value type
 
 Parameters:
 
 elements - Set elements
 
 Returns:
 
 A new HashSet containing the given entries
 - ofAll
```
public static <T> HashSet<T> ofAll(java.util.stream.Stream<? extends T> javaStream)
```
 Creates a HashSet that contains the elements of the given Stream.
 
 Type Parameters:
 
 T - Component type of the Stream.
 
 Parameters:
 
 javaStream - A Stream
 
 Returns:
 
 A HashSet containing the given elements in the same order.
 - ofAll
```
public static HashSet<java.lang.Boolean> ofAll(boolean... elements)
```
 Creates a HashSet from boolean values.
 
 Parameters:
 
 elements - boolean values
 
 Returns:
 
 A new HashSet of Boolean values
 
 Throws:
 
 java.lang.NullPointerException - if elements is null
 - ofAll
```
public static HashSet<java.lang.Byte> ofAll(byte... elements)
```
 Creates a HashSet from byte values.
 
 Parameters:
 
 elements - byte values
 
 Returns:
 
 A new HashSet of Byte values
 
 Throws:
 
 java.lang.NullPointerException - if elements is null
 - ofAll
```
public static HashSet<java.lang.Character> ofAll(char... elements)
```
 Creates a HashSet from char values.
 
 Parameters:
 
 elements - char values
 
 Returns:
 
 A new HashSet of Character values
 
 Throws:
 
 java.lang.NullPointerException - if elements is null
 - ofAll
```
public static HashSet<java.lang.Double> ofAll(double... elements)
```
 Creates a HashSet from double values.
 
 Parameters:
 
 elements - double values
 
 Returns:
 
 A new HashSet of Double values
 
 Throws:
 
 java.lang.NullPointerException - if elements is null
 - ofAll
```
public static HashSet<java.lang.Float> ofAll(float... elements)
```
 Creates a HashSet from float values.
 
 Parameters:
 
 elements - float values
 
 Returns:
 
 A new HashSet of Float values
 
 Throws:
 
 java.lang.NullPointerException - if elements is null
 - ofAll
```
public static HashSet<java.lang.Integer> ofAll(int... elements)
```
 Creates a HashSet from int values.
 
 Parameters:
 
 elements - int values
 
 Returns:
 
 A new HashSet of Integer values
 
 Throws:
 
 java.lang.NullPointerException - if elements is null
 - ofAll
```
public static HashSet<java.lang.Long> ofAll(long... elements)
```
 Creates a HashSet from long values.
 
 Parameters:
 
 elements - long values
 
 Returns:
 
 A new HashSet of Long values
 
 Throws:
 
 java.lang.NullPointerException - if elements is null
 - ofAll
```
public static HashSet<java.lang.Short> ofAll(short... elements)
```
 Creates a HashSet from short values.
 
 Parameters:
 
 elements - short values
 
 Returns:
 
 A new HashSet of Short values
 
 Throws:
 
 java.lang.NullPointerException - if elements is null
 - range
```
public static HashSet<java.lang.Integer> range(int from,
 int toExclusive)
```
 Creates a HashSet of int numbers starting from from, extending to toExclusive - 1.
 Examples:
```
 
 HashSet.range(0, 0) // = HashSet()
 HashSet.range(2, 0) // = HashSet()
 HashSet.range(-2, 2) // = HashSet(-2, -1, 0, 1)
 
 
```
 Parameters:
 
 from - the first number
 
 toExclusive - the last number + 1
 
 Returns:
 
 a range of int values as specified or the empty range if from >= toExclusive
 - range
```
public static HashSet<java.lang.Character> range(char from,
 char toExclusive)
```
 - rangeBy
```
public static HashSet<java.lang.Integer> rangeBy(int from,
 int toExclusive,
 int step)
```
 Creates a HashSet of int numbers starting from from, extending to toExclusive - 1, with step.
 Examples:
```
 
 HashSet.rangeBy(1, 3, 1) // = HashSet(1, 2)
 HashSet.rangeBy(1, 4, 2) // = HashSet(1, 3)
 HashSet.rangeBy(4, 1, -2) // = HashSet(4, 2)
 HashSet.rangeBy(4, 1, 2) // = HashSet()
 
 
```
 Parameters:
 
 from - the first number
 
 toExclusive - the last number + 1
 
 step - the step
 
 Returns:
 
 a range of long values as specified or the empty range if
 from >= toInclusive and step > 0 or
 from <= toInclusive and step < 0
 
 Throws:
 
 java.lang.IllegalArgumentException - if step is zero
 - rangeBy
```
public static HashSet<java.lang.Character> rangeBy(char from,
 char toExclusive,
 int step)
```
 - rangeBy
```
public static HashSet<java.lang.Double> rangeBy(double from,
 double toExclusive,
 double step)
```
 - range
```
public static HashSet<java.lang.Long> range(long from,
 long toExclusive)
```
 Creates a HashSet of long numbers starting from from, extending to toExclusive - 1.
 Examples:
```
 
 HashSet.range(0L, 0L) // = HashSet()
 HashSet.range(2L, 0L) // = HashSet()
 HashSet.range(-2L, 2L) // = HashSet(-2L, -1L, 0L, 1L)
 
 
```
 Parameters:
 
 from - the first number
 
 toExclusive - the last number + 1
 
 Returns:
 
 a range of long values as specified or the empty range if from >= toExclusive
 - rangeBy
```
public static HashSet<java.lang.Long> rangeBy(long from,
 long toExclusive,
 long step)
```
 Creates a HashSet of long numbers starting from from, extending to toExclusive - 1, with step.
 Examples:
```
 
 HashSet.rangeBy(1L, 3L, 1L) // = HashSet(1L, 2L)
 HashSet.rangeBy(1L, 4L, 2L) // = HashSet(1L, 3L)
 HashSet.rangeBy(4L, 1L, -2L) // = HashSet(4L, 2L)
 HashSet.rangeBy(4L, 1L, 2L) // = HashSet()
 
 
```
 Parameters:
 
 from - the first number
 
 toExclusive - the last number + 1
 
 step - the step
 
 Returns:
 
 a range of long values as specified or the empty range if
 from >= toInclusive and step > 0 or
 from <= toInclusive and step < 0
 
 Throws:
 
 java.lang.IllegalArgumentException - if step is zero
 - rangeClosed
```
public static HashSet<java.lang.Integer> rangeClosed(int from,
 int toInclusive)
```
 Creates a HashSet of int numbers starting from from, extending to toInclusive.
 Examples:
```
 
 HashSet.rangeClosed(0, 0) // = HashSet(0)
 HashSet.rangeClosed(2, 0) // = HashSet()
 HashSet.rangeClosed(-2, 2) // = HashSet(-2, -1, 0, 1, 2)
 
 
```
 Parameters:
 
 from - the first number
 
 toInclusive - the last number
 
 Returns:
 
 a range of int values as specified or the empty range if from > toInclusive
 - rangeClosed
```
public static HashSet<java.lang.Character> rangeClosed(char from,
 char toInclusive)
```
 - rangeClosedBy
```
public static HashSet<java.lang.Integer> rangeClosedBy(int from,
 int toInclusive,
 int step)
```
 Creates a HashSet of int numbers starting from from, extending to toInclusive, with step.
 Examples:
```
 
 HashSet.rangeClosedBy(1, 3, 1) // = HashSet(1, 2, 3)
 HashSet.rangeClosedBy(1, 4, 2) // = HashSet(1, 3)
 HashSet.rangeClosedBy(4, 1, -2) // = HashSet(4, 2)
 HashSet.rangeClosedBy(4, 1, 2) // = HashSet()
 
 
```
 Parameters:
 
 from - the first number
 
 toInclusive - the last number
 
 step - the step
 
 Returns:
 
 a range of int values as specified or the empty range if
 from > toInclusive and step > 0 or
 from < toInclusive and step < 0
 
 Throws:
 
 java.lang.IllegalArgumentException - if step is zero
 - rangeClosedBy
```
public static HashSet<java.lang.Character> rangeClosedBy(char from,
 char toInclusive,
 int step)
```
 - rangeClosedBy
```
public static HashSet<java.lang.Double> rangeClosedBy(double from,
 double toInclusive,
 double step)
```
 - rangeClosed
```
public static HashSet<java.lang.Long> rangeClosed(long from,
 long toInclusive)
```
 Creates a HashSet of long numbers starting from from, extending to toInclusive.
 Examples:
```
 
 HashSet.rangeClosed(0L, 0L) // = HashSet(0L)
 HashSet.rangeClosed(2L, 0L) // = HashSet()
 HashSet.rangeClosed(-2L, 2L) // = HashSet(-2L, -1L, 0L, 1L, 2L)
 
 
```
 Parameters:
 
 from - the first number
 
 toInclusive - the last number
 
 Returns:
 
 a range of long values as specified or the empty range if from > toInclusive
 - rangeClosedBy
```
public static HashSet<java.lang.Long> rangeClosedBy(long from,
 long toInclusive,
 long step)
```
 Creates a HashSet of long numbers starting from from, extending to toInclusive, with step.
 Examples:
```
 
 HashSet.rangeClosedBy(1L, 3L, 1L) // = HashSet(1L, 2L, 3L)
 HashSet.rangeClosedBy(1L, 4L, 2L) // = HashSet(1L, 3L)
 HashSet.rangeClosedBy(4L, 1L, -2L) // = HashSet(4L, 2L)
 HashSet.rangeClosedBy(4L, 1L, 2L) // = HashSet()
 
 
```
 Parameters:
 
 from - the first number
 
 toInclusive - the last number
 
 step - the step
 
 Returns:
 
 a range of int values as specified or the empty range if
 from > toInclusive and step > 0 or
 from < toInclusive and step < 0
 
 Throws:
 
 java.lang.IllegalArgumentException - if step is zero
 - add
```
public HashSet<T> add(T element)
```
 Description copied from interface: Set
 
 Add the given element to this set, if it is not already contained.
 
 Specified by:
 
 add in interface Set<T>
 
 Parameters:
 
 element - The element to be added.
 
 Returns:
 
 A new set containing all elements of this set and also element.
 - addAll
```
public HashSet<T> addAll(java.lang.Iterable<? extends T> elements)
```
 Description copied from interface: Set
 
 Adds all of the given elements to this set, if not already contained.
 
 Specified by:
 
 addAll in interface Set<T>
 
 Parameters:
 
 elements - The elements to be added.
 
 Returns:
 
 A new set containing all elements of this set and the given elements, if not already contained.
 - collect
```
public <R> HashSet<R> collect(PartialFunction<? super T,? extends R> partialFunction)
```
 Description copied from interface: Traversable
 Collects all elements that are in the domain of the given partialFunction by mapping the elements to type R.
 More specifically, for each of this elements in iteration order first it is checked
```
 partialFunction.isDefinedAt(element)
 
```
 If the elements makes it through that filter, the mapped instance is added to the result collection
```
 R newElement = partialFunction.apply(element)
 
```
 Note:If this Traversable is ordered (i.e. extends Ordered, the caller of collect has to ensure that the elements are comparable (i.e. extend Comparable).
 Specified by:
 
 collect in interface Set<T>
 
 Specified by:
 
 collect in interface Traversable<T>
 
 Type Parameters:
 
 R - The new element type
 
 Parameters:
 
 partialFunction - A function that is not necessarily defined of all elements of this traversable.
 
 Returns:
 
 A new Traversable instance containing elements of type R
 - contains
```
public 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 Set<T>
 
 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.
 - diff
```
public HashSet<T> diff(Set<? extends T> elements)
```
 Description copied from interface: Set
 
 Calculates the difference between this set and another set.
 See also Set.removeAll(Iterable).
 
 Specified by:
 
 diff in interface Set<T>
 
 Parameters:
 
 elements - Elements to be removed from this set.
 
 Returns:
 
 A new Set containing all elements of this set which are not located in that set.
 - distinct
```
public HashSet<T> distinct()
```
 Description copied from interface: Traversable
 
 Returns a new version of this which contains no duplicates. Elements are compared using equals.
 
 Specified by:
 
 distinct in interface Set<T>
 
 Specified by:
 
 distinct in interface Traversable<T>
 
 Returns:
 
 a new Traversable containing this elements without duplicates
 - distinctBy
```
public HashSet<T> distinctBy(java.util.Comparator<? super T> comparator)
```
 Description copied from interface: Traversable
 
 Returns a new version of this which contains no duplicates. Elements are compared using the given comparator.
 
 Specified by:
 
 distinctBy in interface Set<T>
 
 Specified by:
 
 distinctBy in interface Traversable<T>
 
 Parameters:
 
 comparator - A comparator
 
 Returns:
 
 a new Traversable containing this elements without duplicates
 - distinctBy
```
public  HashSet<T> distinctBy(java.util.function.Function<? super T,? extends U> keyExtractor)
```
 Description copied from interface: Traversable
 
 Returns a new version of this which contains no duplicates. Elements mapped to keys which are compared using equals.
 The elements of the result are determined in the order of their occurrence - first match wins.
 
 Specified by:
 
 distinctBy in interface Set<T>
 
 Specified by:
 
 distinctBy in interface Traversable<T>
 
 Type Parameters:
 
 U - key type
 
 Parameters:
 
 keyExtractor - A key extractor
 
 Returns:
 
 a new Traversable containing this elements without duplicates
 - drop
```
public HashSet<T> drop(int n)
```
 Description copied from interface: Traversable
 
 Drops the first n elements of this or all elements, if this length < n.
 
 Specified by:
 
 drop in interface Set<T>
 
 Specified by:
 
 drop in interface Traversable<T>
 
 Parameters:
 
 n - The number of elements to drop.
 
 Returns:
 
 a new instance consisting of all elements of this except the first n ones, or else the empty instance, if this has less than n elements.
 - dropRight
```
public HashSet<T> dropRight(int n)
```
 Description copied from interface: Traversable
 
 Drops the last n elements of this or all elements, if this length < n.
 
 Specified by:
 
 dropRight in interface Set<T>
 
 Specified by:
 
 dropRight in interface Traversable<T>
 
 Parameters:
 
 n - The number of elements to drop.
 
 Returns:
 
 a new instance consisting of all elements of this except the last n ones, or else the empty instance, if this has less than n elements.
 - dropUntil
```
public HashSet<T> dropUntil(java.util.function.Predicate<? super T> predicate)
```
 Description copied from interface: Traversable
 
 Drops elements until the predicate holds for the current element.
 
 Specified by:
 
 dropUntil in interface Set<T>
 
 Specified by:
 
 dropUntil in interface Traversable<T>
 
 Parameters:
 
 predicate - A condition tested subsequently for this elements.
 
 Returns:
 
 a new instance consisting of all elements starting from the first one which does satisfy the given predicate.
 - dropWhile
```
public HashSet<T> dropWhile(java.util.function.Predicate<? super T> predicate)
```
 Description copied from interface: Traversable
 
 Drops elements while the predicate holds for the current element.
 Note: This is essentially the same as dropUntil(predicate.negate()). It is intended to be used with method references, which cannot be negated directly.
 
 Specified by:
 
 dropWhile in interface Set<T>
 
 Specified by:
 
 dropWhile in interface Traversable<T>
 
 Parameters:
 
 predicate - A condition tested subsequently for this elements.
 
 Returns:
 
 a new instance consisting of all elements starting from the first one which does not satisfy the given predicate.
 - filter
```
public HashSet<T> filter(java.util.function.Predicate<? super T> predicate)
```
 Description copied from interface: Traversable
 
 Returns a new traversable consisting of all elements which satisfy the given predicate.
 
 Specified by:
 
 filter in interface Set<T>
 
 Specified by:
 
 filter in interface Traversable<T>
 
 Parameters:
 
 predicate - A predicate
 
 Returns:
 
 a new traversable
 - filterNot
```
public HashSet<T> filterNot(java.util.function.Predicate<? super T> predicate)
```
 Description copied from interface: Traversable
 Returns a new traversable consisting of all elements which do not satisfy the given predicate.
 The default implementation is equivalent to
```
 filter(predicate.negate()
```
 Specified by:
 
 filterNot in interface Set<T>
 
 Specified by:
 
 filterNot in interface Traversable<T>
 
 Parameters:
 
 predicate - A predicate
 
 Returns:
 
 a new traversable
 - flatMap
```
public  HashSet flatMap(java.util.function.Function<? super T,? extends java.lang.Iterable<? extends U>> mapper)
```
 Description copied from interface: Traversable
 
 FlatMaps this Traversable.
 
 Specified by:
 
 flatMap in interface Set<T>
 
 Specified by:
 
 flatMap in interface Traversable<T>
 
 Type Parameters:
 
 U - The resulting component type.
 
 Parameters:
 
 mapper - A mapper
 
 Returns:
 
 A new Traversable instance.
 - foldRight
```
public  U foldRight(U zero,
 java.util.function.BiFunction<? super T,? super U,? extends U> f)
```
 Description copied from interface: Traversable
 Folds this elements from the right, starting with zero and successively calling combine.
 Example:
```
 
 // = "!cba"
 List("a", "b", "c").foldRight("!", (x, xs) -> xs + x)
 
```
 Specified by:
 
 foldRight in interface Foldable<T>
 
 Specified by:
 
 foldRight in interface Traversable<T>
 
 Type Parameters:
 
 U - the type of the folded value
 
 Parameters:
 
 zero - A zero element to start with.
 
 f - A function which combines elements.
 
 Returns:
 
 a folded value
 - groupBy
```
public <C> Map<C,HashSet<T>> groupBy(java.util.function.Function<? super T,? extends C> classifier)
```
 Description copied from interface: Traversable
 
 Groups this elements by classifying the elements.
 
 Specified by:
 
 groupBy in interface Set<T>
 
 Specified by:
 
 groupBy in interface Traversable<T>
 
 Type Parameters:
 
 C - classified class type
 
 Parameters:
 
 classifier - A function which classifies elements into classes
 
 Returns:
 
 A Map containing the grouped elements
 
 See Also:
 
 Traversable.arrangeBy(Function)
 - grouped
```
public Iterator<HashSet<T>> grouped(int size)
```
 Description copied from interface: Traversable
 Groups this Traversable into fixed size blocks.
 Let length be the length of this Iterable. Then grouped is defined as follows:
 - If this.isEmpty(), the resulting Iterator is empty.
 - If size <= length, the resulting Iterator will contain length / size blocks of size size and maybe a non-empty block of size length % size, if there are remaining elements.
 - If size > length, the resulting Iterator will contain one 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]]
 
 
```
 Please note that grouped(int) is a special case of Traversable.sliding(int, int), i.e. grouped(size) is the same as sliding(size, size).
 Specified by:
 
 grouped in interface Set<T>
 
 Specified by:
 
 grouped in interface Traversable<T>
 
 Parameters:
 
 size - a positive block size
 
 Returns:
 
 A new Iterator of grouped blocks of the given size
 - hasDefiniteSize
```
public boolean hasDefiniteSize()
```
 Description copied from interface: Traversable
 
 Checks if this Traversable is known to have a finite size.
 This method should be implemented by classes only, i.e. not by interfaces.
 
 Specified by:
 
 hasDefiniteSize in interface Traversable<T>
 
 Returns:
 
 true, if this Traversable is known to have a finite size, false otherwise.
 - head
```
public T head()
```
 Description copied from interface: Traversable
 
 Returns the first element of a non-empty Traversable.
 
 Specified by:
 
 head in interface Traversable<T>
 
 Returns:
 
 The first element of this Traversable.
 - headOption
```
public Option<T> headOption()
```
 Description copied from interface: Traversable
 
 Returns the first element of a non-empty Traversable as Option.
 
 Specified by:
 
 headOption in interface Traversable<T>
 
 Returns:
 
 Some(element) or None if this is empty.
 - init
```
public HashSet<T> init()
```
 Description copied from interface: Traversable
 
 Dual of Traversable.tail(), returning all elements except the last.
 
 Specified by:
 
 init in interface Set<T>
 
 Specified by:
 
 init in interface Traversable<T>
 
 Returns:
 
 a new instance containing all elements except the last.
 - initOption
```
public Option<HashSet<T>> initOption()
```
 Description copied from interface: Traversable
 
 Dual of Traversable.tailOption(), returning all elements except the last as Option.
 
 Specified by:
 
 initOption in interface Set<T>
 
 Specified by:
 
 initOption in interface Traversable<T>
 
 Returns:
 
 Some(traversable) or None if this is empty.
 - intersect
```
public HashSet<T> intersect(Set<? extends T> elements)
```
 Description copied from interface: Set
 
 Computes the intersection between this set and another set.
 See also Set.retainAll(Iterable).
 
 Specified by:
 
 intersect in interface Set<T>
 
 Parameters:
 
 elements - the set to intersect with.
 
 Returns:
 
 A new Set consisting of all elements that are both in this set and in the given set that.
 - isAsync
```
public boolean isAsync()
```
 A HashSet is computed synchronously.
 
 Specified by:
 
 isAsync in interface Value<T>
 
 Returns:
 
 false
 - isEmpty
```
public boolean isEmpty()
```
 Description copied from interface: Traversable
 
 Checks if this Traversable is empty.
 
 Specified by:
 
 isEmpty in interface Traversable<T>
 
 Specified by:
 
 isEmpty in interface Value<T>
 
 Returns:
 
 true, if this Traversable contains no elements, false otherwise.
 - isLazy
```
public boolean isLazy()
```
 A HashSet is computed eagerly.
 
 Specified by:
 
 isLazy in interface Value<T>
 
 Returns:
 
 false
 - isTraversableAgain
```
public boolean isTraversableAgain()
```
 Description copied from interface: Traversable
 
 Checks if this Traversable can be repeatedly traversed.
 This method should be implemented by classes only, i.e. not by interfaces.
 
 Specified by:
 
 isTraversableAgain in interface Traversable<T>
 
 Returns:
 
 true, if this Traversable is known to be traversable repeatedly, false otherwise.
 - iterator
```
public Iterator<T> iterator()
```
 Description copied from interface: Traversable
 
 An iterator by means of head() and tail(). Subclasses may want to override this method.
 
 Specified by:
 
 iterator in interface Set<T>
 
 Specified by:
 
 iterator in interface Traversable<T>
 
 Specified by:
 
 iterator in interface Value<T>
 
 Specified by:
 
 iterator in interface java.lang.Iterable<T>
 
 Returns:
 
 A new Iterator of this Traversable elements.
 - last
```
public T last()
```
 Description copied from interface: Traversable
 
 Dual of Traversable.head(), returning the last element.
 
 Specified by:
 
 last in interface Traversable<T>
 
 Returns:
 
 the last element.
 - length
```
public int length()
```
 Description copied from interface: Traversable
 
 Computes the number of elements of this Traversable.
 Same as Traversable.size().
 
 Specified by:
 
 length in interface Set<T>
 
 Specified by:
 
 length in interface Traversable<T>
 
 Returns:
 
 the number of elements
 - map
```
public  HashSet map(java.util.function.Function<? super T,? extends U> mapper)
```
 Description copied from interface: Traversable
 
 Maps the elements of this Traversable to elements of a new type preserving their order, if any.
 
 Specified by:
 
 map in interface Set<T>
 
 Specified by:
 
 map in interface Traversable<T>
 
 Specified by:
 
 map in interface Value<T>
 
 Type Parameters:
 
 U - Component type of the target Traversable
 
 Parameters:
 
 mapper - A mapper.
 
 Returns:
 
 a mapped Traversable
 - mkString
```
public java.lang.String mkString(java.lang.CharSequence prefix,
 java.lang.CharSequence delimiter,
 java.lang.CharSequence suffix)
```
 Description copied from interface: Traversable
 
 Joins the string representations of this elements using a specific delimiter, prefix and suffix.
 Example: List.of("a", "b", "c").mkString("Chars(", ", ", ")") = "Chars(a, b, c)"
 
 Specified by:
 
 mkString in interface Traversable<T>
 
 Parameters:
 
 prefix - prefix of the resulting string
 
 delimiter - A delimiter string put between string representations of elements of this
 
 suffix - suffix of the resulting string
 
 Returns:
 
 a new String
 - orElse
```
public HashSet<T> orElse(java.lang.Iterable<? extends T> other)
```
 Description copied from interface: Traversable
 
 Returns this Traversable if it is nonempty, otherwise return the alternative.
 
 Specified by:
 
 orElse in interface Set<T>
 
 Specified by:
 
 orElse in interface Traversable<T>
 
 Parameters:
 
 other - An alternative Traversable
 
 Returns:
 
 this Traversable if it is nonempty, otherwise return the alternative.
 - orElse
```
public HashSet<T> orElse(java.util.function.Supplier<? extends java.lang.Iterable<? extends T>> supplier)
```
 Description copied from interface: Traversable
 
 Returns this Traversable if it is nonempty, otherwise return the result of evaluating supplier.
 
 Specified by:
 
 orElse in interface Set<T>
 
 Specified by:
 
 orElse in interface Traversable<T>
 
 Parameters:
 
 supplier - An alternative Traversable supplier
 
 Returns:
 
 this Traversable if it is nonempty, otherwise return the result of evaluating supplier.
 - partition
```
public Tuple2<HashSet<T>,HashSet<T>> partition(java.util.function.Predicate<? super T> predicate)
```
 Description copied from interface: Traversable
 
 Creates a partition of this Traversable by splitting this elements in two in distinct traversables according to a predicate.
 
 Specified by:
 
 partition in interface Set<T>
 
 Specified by:
 
 partition in interface Traversable<T>
 
 Parameters:
 
 predicate - A predicate which classifies an element if it is in the first or the second traversable.
 
 Returns:
 
 A disjoint union of two traversables. The first Traversable contains all elements that satisfy the given predicate, the second Traversable contains all elements that don't. The original order of elements is preserved.
 - peek
```
public HashSet<T> peek(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 Set<T>
 
 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
 - remove
```
public HashSet<T> remove(T key)
```
 Description copied from interface: Set
 
 Removes a specific element from this set, if present.
 
 Specified by:
 
 remove in interface Set<T>
 
 Parameters:
 
 key - The element to be removed from this set.
 
 Returns:
 
 A new set consisting of the elements of this set, without the given element.
 - removeAll
```
public HashSet<T> removeAll(java.lang.Iterable<? extends T> elements)
```
 Description copied from interface: Set
 
 Removes all of the given elements from this set, if present.
 
 Specified by:
 
 removeAll in interface Set<T>
 
 Parameters:
 
 elements - The elements to be removed from this set.
 
 Returns:
 
 A new set consisting of the elements of this set, without the given elements.
 - replace
```
public HashSet<T> replace(T currentElement,
 T newElement)
```
 Description copied from interface: Traversable
 
 Replaces the first occurrence (if exists) of the given currentElement with newElement.
 
 Specified by:
 
 replace in interface Set<T>
 
 Specified by:
 
 replace in interface Traversable<T>
 
 Parameters:
 
 currentElement - An element to be substituted.
 
 newElement - A replacement for currentElement.
 
 Returns:
 
 a Traversable containing all elements of this where the first occurrence of currentElement is replaced with newElement.
 - replaceAll
```
public HashSet<T> replaceAll(T currentElement,
 T newElement)
```
 Description copied from interface: Traversable
 
 Replaces all occurrences of the given currentElement with newElement.
 
 Specified by:
 
 replaceAll in interface Set<T>
 
 Specified by:
 
 replaceAll in interface Traversable<T>
 
 Parameters:
 
 currentElement - An element to be substituted.
 
 newElement - A replacement for currentElement.
 
 Returns:
 
 a Traversable containing all elements of this where all occurrences of currentElement are replaced with newElement.
 - retainAll
```
public HashSet<T> retainAll(java.lang.Iterable<? extends T> elements)
```
 Description copied from interface: Traversable
 
 Keeps all occurrences of the given elements from this.
 
 Specified by:
 
 retainAll in interface Set<T>
 
 Specified by:
 
 retainAll in interface Traversable<T>
 
 Parameters:
 
 elements - Elements to be kept.
 
 Returns:
 
 a Traversable containing all occurrences of the given elements.
 - scan
```
public HashSet<T> scan(T zero,
 java.util.function.BiFunction<? super T,? super T,? extends T> operation)
```
 Description copied from interface: Traversable
 
 Computes a prefix scan of the elements of the collection. Note: The neutral element z may be applied more than once.
 
 Specified by:
 
 scan in interface Set<T>
 
 Specified by:
 
 scan in interface Traversable<T>
 
 Parameters:
 
 zero - neutral element for the operator op
 
 operation - the associative operator for the scan
 
 Returns:
 
 a new traversable collection containing the prefix scan of the elements in this traversable collection
 - scanLeft
```
public  HashSet scanLeft(U zero,
 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 going left to right. Note: will not terminate for infinite-sized collections. Note: might return different results for different runs, unless the underlying collection type is ordered.
 
 Specified by:
 
 scanLeft in interface Set<T>
 
 Specified by:
 
 scanLeft in interface Traversable<T>
 
 Type Parameters:
 
 U - the type of the elements in the resulting collection
 
 Parameters:
 
 zero - the initial value
 
 operation - the binary operator applied to the intermediate result and the element
 
 Returns:
 
 collection with intermediate results
 - scanRight
```
public  HashSet scanRight(U zero,
 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 going right to left. The head of the collection is the last cumulative result. Note: will not terminate for infinite-sized collections. Note: might return different results for different runs, unless the underlying collection type is ordered.
 
 Specified by:
 
 scanRight in interface Set<T>
 
 Specified by:
 
 scanRight in interface Traversable<T>
 
 Type Parameters:
 
 U - the type of the elements in the resulting collection
 
 Parameters:
 
 zero - the initial value
 
 operation - the binary operator applied to the intermediate result and the element
 
 Returns:
 
 collection with intermediate results
 - slideBy
```
public Iterator<HashSet<T>> slideBy(java.util.function.Function<? super T,?> classifier)
```
 Description copied from interface: Traversable
 Slides a non-overlapping window of a variable size over this Traversable.
 Each window contains elements with the same class, as determined by classifier. Two consecutive values in this Traversable will be in the same window only if classifier returns equal values for them. Otherwise, the values will constitute the last element of the previous window and the first element of the next window.
 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 Set<T>
 
 Specified by:
 
 slideBy in interface Traversable<T>
 
 Parameters:
 
 classifier - A function which classifies elements into classes
 
 Returns:
 
 A new Iterator of windows of the grouped elements
 - sliding
```
public Iterator<HashSet<T>> sliding(int size)
```
 Description copied from interface: Traversable
 
 Slides a window of a specific size and step size 1 over this Traversable by calling Traversable.sliding(int, int).
 
 Specified by:
 
 sliding in interface Set<T>
 
 Specified by:
 
 sliding in interface Traversable<T>
 
 Parameters:
 
 size - a positive window size
 
 Returns:
 
 a new Iterator of windows of a specific size using step size 1
 - sliding
```
public Iterator<HashSet<T>> sliding(int size,
 int step)
```
 Description copied from interface: Traversable
 Slides a window of a specific size and step size 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]]
 
 
```
 Specified by:
 
 sliding in interface Set<T>
 
 Specified by:
 
 sliding in interface Traversable<T>
 
 Parameters:
 
 size - a positive window size
 
 step - a positive step size
 
 Returns:
 
 a new Iterator of windows of a specific size using a specific step size
 - span
```
public Tuple2<HashSet<T>,HashSet<T>> span(java.util.function.Predicate<? super T> predicate)
```
 Description copied from interface: Traversable
 
 Returns a tuple where the first element is the longest prefix of elements that satisfy the given predicate and the second element is the remainder.
 
 Specified by:
 
 span in interface Set<T>
 
 Specified by:
 
 span in interface Traversable<T>
 
 Parameters:
 
 predicate - A predicate.
 
 Returns:
 
 a Tuple containing the longest prefix of elements that satisfy p and the remainder.
 - spliterator
```
public java.util.Spliterator<T> spliterator()
```
 Specified by:
 
 spliterator in interface Traversable<T>
 
 Specified by:
 
 spliterator in interface Value<T>
 
 Specified by:
 
 spliterator in interface java.lang.Iterable<T>
 - tail
```
public HashSet<T> tail()
```
 Description copied from interface: Traversable
 
 Drops the first element of a non-empty Traversable.
 
 Specified by:
 
 tail in interface Set<T>
 
 Specified by:
 
 tail in interface Traversable<T>
 
 Returns:
 
 A new instance of Traversable containing all elements except the first.
 - tailOption
```
public Option<HashSet<T>> tailOption()
```
 Description copied from interface: Traversable
 
 Drops the first element of a non-empty Traversable and returns an Option.
 
 Specified by:
 
 tailOption in interface Set<T>
 
 Specified by:
 
 tailOption in interface Traversable<T>
 
 Returns:
 
 Some(traversable) or None if this is empty.
 - take
```
public HashSet<T> take(int n)
```
 Description copied from interface: Traversable
 
 Takes the first n elements of this or all elements, if this length < n.
 The result is equivalent to sublist(0, max(0, min(length(), n))) but does not throw if n < 0 or n > length().
 In the case of n < 0 the empty instance is returned, in the case of n > length() this is returned.
 
 Specified by:
 
 take in interface Set<T>
 
 Specified by:
 
 take in interface Traversable<T>
 
 Parameters:
 
 n - The number of elements to take.
 
 Returns:
 
 A new instance consisting of the first n elements of this or all elements, if this has less than n elements.
 - takeRight
```
public HashSet<T> takeRight(int n)
```
 Description copied from interface: Traversable
 
 Takes the last n elements of this or all elements, if this length < n.
 The result is equivalent to sublist(max(0, min(length(), length() - n)), n), i.e. takeRight will not throw if n < 0 or n > length().
 In the case of n < 0 the empty instance is returned, in the case of n > length() this is returned.
 
 Specified by:
 
 takeRight in interface Set<T>
 
 Specified by:
 
 takeRight in interface Traversable<T>
 
 Parameters:
 
 n - The number of elements to take.
 
 Returns:
 
 A new instance consisting of the last n elements of this or all elements, if this has less than n elements.
 - takeUntil
```
public HashSet<T> takeUntil(java.util.function.Predicate<? super T> predicate)
```
 Description copied from interface: Traversable
 
 Takes elements until the predicate holds for the current element.
 Note: This is essentially the same as takeWhile(predicate.negate()). It is intended to be used with method references, which cannot be negated directly.
 
 Specified by:
 
 takeUntil in interface Set<T>
 
 Specified by:
 
 takeUntil in interface Traversable<T>
 
 Parameters:
 
 predicate - A condition tested subsequently for this elements.
 
 Returns:
 
 a new instance consisting of all elements before the first one which does satisfy the given predicate.
 - takeWhile
```
public HashSet<T> takeWhile(java.util.function.Predicate<? super T> predicate)
```
 Description copied from interface: Traversable
 
 Takes elements while the predicate holds for the current element.
 
 Specified by:
 
 takeWhile in interface Set<T>
 
 Specified by:
 
 takeWhile in interface Traversable<T>
 
 Parameters:
 
 predicate - A condition tested subsequently for the contained elements.
 
 Returns:
 
 a new instance consisting of all elements before the first one which does not satisfy the given predicate.
 - transform
```
public  U transform(java.util.function.Function<? super HashSet<T>,? extends U> f)
```
 Transforms this HashSet.
 
 Type Parameters:
 
 U - Type of transformation result
 
 Parameters:
 
 f - A transformation
 
 Returns:
 
 An instance of type U
 
 Throws:
 
 java.lang.NullPointerException - if f is null
 - toJavaSet
```
public java.util.HashSet<T> toJavaSet()
```
 Description copied from interface: Set
 
 Converts this Vavr Set to a java.util.Set while preserving characteristics like insertion order (LinkedHashSet) and sort order (SortedSet).
 
 Specified by:
 
 toJavaSet in interface Set<T>
 
 Specified by:
 
 toJavaSet in interface Value<T>
 
 Returns:
 
 a new java.util.Set instance
 - union
```
public HashSet<T> union(Set<? extends T> elements)
```
 Description copied from interface: Set
 
 Adds all of the elements of that set to this set, if not already present.
 See also Set.addAll(Iterable).
 
 Specified by:
 
 union in interface Set<T>
 
 Parameters:
 
 elements - The set to form the union with.
 
 Returns:
 
 A new set that contains all distinct elements of this and that set.
 - zip
```
public  HashSet<Tuple2<T,U>> zip(java.lang.Iterable<? extends U> that)
```
 Description copied from interface: Traversable
 
 Returns a traversable formed from this traversable and another Iterable collection by combining corresponding elements in pairs. If one of the two iterables is longer than the other, its remaining elements are ignored.
 The length of the returned traversable is the minimum of the lengths of this traversable and that iterable.
 
 Specified by:
 
 zip in interface Set<T>
 
 Specified by:
 
 zip in interface Traversable<T>
 
 Type Parameters:
 
 U - The type of the second half of the returned pairs.
 
 Parameters:
 
 that - The Iterable providing the second half of each result pair.
 
 Returns:
 
 a new traversable containing pairs consisting of corresponding elements of this traversable and that iterable.
 - zipWith
```
public <U,R> HashSet<R> zipWith(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 formed from this traversable and another Iterable collection by mapping elements. If one of the two iterables is longer than the other, its remaining elements are ignored.
 The length of the returned traversable is the minimum of the lengths of this traversable and that iterable.
 
 Specified by:
 
 zipWith in interface Set<T>
 
 Specified by:
 
 zipWith in interface Traversable<T>
 
 Type Parameters:
 
 U - The type of the second parameter of the mapper.
 
 R - The type of the mapped elements.
 
 Parameters:
 
 that - The Iterable providing the second parameter of the mapper.
 
 mapper - a mapper.
 
 Returns:
 
 a new traversable containing mapped elements of this traversable and that iterable.
 - zipAll
```
public  HashSet<Tuple2<T,U>> zipAll(java.lang.Iterable<? extends U> that,
 T thisElem,
 U thatElem)
```
 Description copied from interface: Traversable
 
 Returns a traversable formed from this traversable and another Iterable by combining corresponding elements in pairs. If one of the two collections is shorter than the other, placeholder elements are used to extend the shorter collection to the length of the longer.
 The length of the returned traversable is the maximum of the lengths of this traversable and that iterable.
 Special case: if this traversable is shorter than that elements, and that elements contains duplicates, the resulting traversable may be shorter than the maximum of the lengths of this and that because a traversable contains an element at most once.
 If this Traversable is shorter than that, thisElem values are used to fill the result. If that is shorter than this Traversable, thatElem values are used to fill the result.
 
 Specified by:
 
 zipAll in interface Set<T>
 
 Specified by:
 
 zipAll in interface Traversable<T>
 
 Type Parameters:
 
 U - The type of the second half of the returned pairs.
 
 Parameters:
 
 that - The Iterable providing the second half of each result pair.
 
 thisElem - The element to be used to fill up the result if this traversable is shorter than that.
 
 thatElem - The element to be used to fill up the result if that is shorter than this traversable.
 
 Returns:
 
 A new traversable containing pairs consisting of corresponding elements of this traversable and that.
 - zipWithIndex
```
public HashSet<Tuple2<T,java.lang.Integer>> zipWithIndex()
```
 Description copied from interface: Traversable
 
 Zips this traversable with its indices.
 
 Specified by:
 
 zipWithIndex in interface Set<T>
 
 Specified by:
 
 zipWithIndex in interface Traversable<T>
 
 Returns:
 
 A new traversable containing all elements of this traversable paired with their index, starting with 0.
 - zipWithIndex
```
public  HashSet zipWithIndex(java.util.function.BiFunction<? super T,? super java.lang.Integer,? extends U> mapper)
```
 Description copied from interface: Traversable
 
 Zips this traversable with its indices by applying mapper provided.
 
 Specified by:
 
 zipWithIndex in interface Set<T>
 
 Specified by:
 
 zipWithIndex in interface Traversable<T>
 
 Type Parameters:
 
 U - The type of the mapped elements.
 
 Parameters:
 
 mapper - a mapper.
 
 Returns:
 
 a new traversable containing elements of this traversable, zipped with indices, and mapped with mapper provided.
 - equals
```
public boolean equals(java.lang.Object o)
```
 Description copied from interface: Traversable
 In Vavr there are four basic classes of collections:
 - Seq (sequential elements)
 - Set (distinct elements)
 - Map (indexed elements)
 - Multimap (indexed collections)
 Two collection instances of these classes are equal if and only if both collections
 - belong to the same basic collection class (Seq, Set, Map or Multimap)
 - contain the same elements
 - have the same element order, if the collections are of type Seq
 Two Map/Multimap elements, resp. entries, (key1, value1) and (key2, value2) are equal, if the keys are equal and the values are equal.
 Notes:
 - No collection instance equals null, e.g. Queue(1) not equals null.
 - Nulls are allowed and handled as expected, e.g. List(null, 1) equals Stream(null, 1) and HashMap((null, 1)) equals LinkedHashMap((null, 1)).
 - The element order is taken into account for Seq only. E.g. List(null, 1) not equals Stream(1, null) and HashMap((null, 1), ("a", null)) equals LinkedHashMap(("a", null), (null, 1)). The reason is, that we do not know which implementations we compare when having two instances of type Map, Multimap or Set (see Liskov Substitution Principle).
 - Other collection classes are equal if their types are equal and their elements are equal (in iteration order).
 - Iterator equality is defined to be object reference equality.
 Specified by:
 
 equals in interface Traversable<T>
 
 Specified by:
 
 equals in interface Value<T>
 
 Overrides:
 
 equals in class java.lang.Object
 
 Parameters:
 
 o - an object, may be null
 
 Returns:
 
 true, if this collection equals the given object according to the rules described above, false otherwise.
 - hashCode
```
public int hashCode()
```
 Description copied from interface: Traversable
 Returns the hash code of this collection.
 We distinguish between two types of hashes, those for collections with predictable iteration order (like Seq) and those with arbitrary iteration order (like Set, Map and Multimap).
 In all cases the hash of an empty collection is defined to be 1.
 Collections with predictable iteration order are hashed as follows:
```
 int hash = 1;
 for (T t : this) { hash = hash * 31 + Objects.hashCode(t); }
 
```
 Collections with arbitrary iteration order are hashed in a way such that the hash of a fixed number of elements is independent of their iteration order.
```
 int hash = 1;
 for (T t : this) { hash += Objects.hashCode(t); }
 
```
 Please note that the particular hashing algorithms may change in a future version of Vavr.
 Generally, hash codes of collections aren't cached in Vavr (opposed to the size/length). Storing hash codes in order to reduce the time complexity would increase the memory footprint. Persistent collections are built upon tree structures, it allows us to implement efficient memory sharing. A drawback of tree structures is that they make it necessary to store collection attributes at each tree node (read: element).
 The computation of the hash code is linear in time, i.e. O(n). If the hash code of a collection is re-calculated often, e.g. when using a List as HashMap key, we might want to cache the hash code. This can be achieved by simply using a wrapper class, which is not included in Vavr but could be implemented like this:
```
 public final class Hashed<K> {

 private final K key;
 private final Lazy<Integer> hashCode;

 public Hashed(K key) {
 this.key = key;
 this.hashCode = Lazy.of(() -> Objects.hashCode(key));
 }

 public K key() {
 return key;
 }

 &#64;Override
 public boolean equals(Object o) {
 if (o == key) {
 return true;
 } else if (key != null && o instanceof Hashed) {
 final Hashed that = (Hashed) o;
 return key.equals(that.key);
 } else {
 return false;
 }
 }

 &#64;Override
 public int hashCode() {
 return hashCode.get();
 }

 &#64;Override
 public String toString() {
 return "Hashed(" + (key == null ? "null" : key.toString()) + ")";
 }
 }
 
```
 Specified by:
 
 hashCode in interface Traversable<T>
 
 Specified by:
 
 hashCode in interface Value<T>
 
 Overrides:
 
 hashCode in class java.lang.Object
 
 Returns:
 
 The hash code of this collection
 - stringPrefix
```
public java.lang.String stringPrefix()
```
 Description copied from interface: Value
 
 Returns the name of this Value type, which is used by toString().
 
 Specified by:
 
 stringPrefix in interface Value<T>
 
 Returns:
 
 This type name.
 - toString
```
public java.lang.String toString()
```
 Description copied from interface: Value
 
 Clarifies that values have a proper toString() method implemented.
 See Object.toString().
 
 Specified by:
 
 toString in interface Value<T>
 
 Overrides:
 
 toString in class java.lang.Object
 
 Returns:
 
 A String representation of this object

Class HashSet<T>

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface io.vavr.collection.Set

Methods inherited from interface io.vavr.collection.Traversable

Methods inherited from interface io.vavr.Value

Method Detail

empty

collector

narrow

of

of

tabulate

fill

ofAll

ofAll

ofAll

ofAll

ofAll

ofAll

ofAll

ofAll

ofAll

ofAll

range

range

rangeBy

rangeBy

rangeBy

range

rangeBy

rangeClosed

rangeClosed

rangeClosedBy

rangeClosedBy

rangeClosedBy

rangeClosed

rangeClosedBy

add

addAll

collect

contains

diff

distinct

distinctBy

distinctBy

drop

dropRight

dropUntil

dropWhile

filter

filterNot

flatMap

foldRight

groupBy

grouped

hasDefiniteSize

head

headOption

init

initOption

intersect

isAsync

isEmpty

isLazy

isTraversableAgain

iterator

last

length

map

mkString

orElse

orElse

partition

peek

remove

removeAll

replace

replaceAll

retainAll