A Collection of unique values with O(log32 N)
adds and has.
type Set<T> extends Collection.Set<T>
When iterating a Set, the entries will be (value, value) pairs. Iteration order of a Set is undefined, however is stable. Multiple iterations of the same Set will iterate in the same order.
Set values, like Map keys, may be of any type. Equality is determined by Immutable.is
enabling Sets to uniquely include other Immutable collections, custom value types, and NaN.
Create a new Immutable Set.
Set<T>(collection?: Iterable<T> | ArrayLike<T>): Set<T>
Note: Set
is a factory function and not a class, and does not use the new
keyword during construction.
True if the provided value is a Set.
Set.isSet(maybeSet: unknown): boolean
Creates a new Set containing values
.
Set.of<T>(...values: Array<T>): Set<T>
Set.fromKeys()
creates a new immutable Set containing the keys from this Collection or JavaScript Object.
Set.fromKeys<T>(iter: Collection.Keyed<T, unknown>): Set<T>
Set.fromKeys<T>(iter: Collection<T, unknown>): Set<T>
Set.fromKeys(obj: { [key: string]: unknown }): Set<string>
Creates a Set that contains every value shared between all of the provided Sets.
Set.intersect<T>(sets: Iterable<Iterable<T>>): Set<T>
Creates a Set that contains all values contained in any of the provided Sets.
Set.union<T>(sets: Iterable<Iterable<T>>): Set<T>
The number of items in this Set.
size: number
Returns a new Set which includes this value.
add(value: T): Set<T>
Note: add
can be used in withMutations
.
Returns a new Set which excludes this value.
delete(value: T): Set<T>
Note: delete
cannot be safely used in IE8, use remove
if supporting old browsers.
Note: delete
can be used in withMutations
.
Returns a new Set containing no values.
clear(): Set<T>
Note: clear
can be used in withMutations
.
Returns a Set including any value from collections
that does not already exist in this Set.
union<C>(...collections: Array<Iterable<C>>): Set<T | C>
Note: union
can be used in withMutations
.
Returns a Set which has removed any values not also contained within collections
.
intersect(...collections: Array<Iterable<T>>): Set<T>
Note: intersect
can be used in withMutations
.
Returns a Set excluding any values contained within collections
.
subtract(...collections: Array<Iterable<T>>): Set<T>
Note: subtract
can be used in withMutations
.
Note: Not all methods can be used on a mutable collection or within withMutations
! Check the documentation for each method to see if it allows being used in withMutations
.
withMutations(mutator: (mutable: this) => unknown): Set<T>
asMutable(): Set<T>
Note: Not all methods can be used on a mutable collection or within withMutations
! Check the documentation for each method to see if it allows being used in withMutations
.
Returns true if this is a mutable copy (see asMutable()
) and mutative alterations have been applied.
wasAltered(): boolean
The yin to asMutable
's yang. Because it applies to mutable collections, this operation is mutable and may return itself (though may not return itself, i.e. if the result is an empty collection). Once performed, the original mutable copy must no longer be mutated since it may be the immutable result.
asImmutable(): Set<T>
If possible, use withMutations
to work with temporary mutable copies as it provides an easier to use API and considers many common optimizations.
Returns a new Set with values passed through a mapper
function.
map<M>(mapper: (value: T, key: T, iter: this) => M, context?: unknown): Set<M>
Flat-maps the Set, returning a new Set.
Similar to set.map(...).flatten(true)
.
flatMap<M>(mapper: (value: T, key: T, iter: this) => Iterable<M>, context?: unknown): Set<M>
Returns a new Set with only the values for which the predicate
function returns true.
Note: filter()
always returns a new instance, even if it results in not filtering out any values.
filter(predicate: (value: T, key: T, iter: this) => boolean, context?: unknown): Set<T>
Returns a new Set with only the values for which the predicate
function returns false.
filterNot(predicate: (value: T, key: T, iter: this) => boolean, context?: unknown): Set<T>
Note: filterNot()
always returns a new instance, even if it results in not filtering out any values.
Returns a new Set with the values for which the predicate
function returns false and another for which is returns true.
partition(predicate: (this: C, value: T, key: T, iter: this) => boolean, context?: C): [Set<T>, Set<T>]
Returns an OrderedSet of the same type which includes the same entries, stably sorted by using a comparator
.
sort(comparator?: Comparator<T>): OrderedSet<T>
If a comparator
is not provided, a default comparator uses <
and >
.
comparator(valueA, valueB)
:
0
if the elements should not be swapped.-1
(or any negative number) if valueA
comes before valueB
1
(or any positive number) if valueA
comes after valueB
PairSorting
enum typeNote: sort()
Always returns a new instance, even if the original was already sorted.
Note: This is always an eager operation.
Like sort
, but also accepts a comparatorValueMapper
which allows for sorting by more sophisticated means:
sortBy<C>(comparatorValueMapper: (value: T, key: T, iter: this) => C, comparator?: (valueA: C, valueB: C) => number): this & OrderedSet<T>
Note: sortBy()
Always returns a new instance, even if the original was already sorted.
Note: This is always an eager operation.
Returns a new Set with the order of the values reversed.
reverse(): Set<T>
Returns a Map
of Set
, grouped by the return value of the grouper
function.
groupBy<G>(grouper: (value: T, key: T, iter: this) => G, context?: unknown): Map<G, Set<T>>
Note: This is not a lazy operation.
Deeply converts this Set to equivalent native JavaScript Array.
toJS(): Array<DeepCopy<T>>
Shallowly converts this Set to equivalent native JavaScript Array.
toJSON(): Array<T>
Shallowly converts this collection to an Array.
toArray(): Array<T>
Shallowly converts this Collection to an Object.
toObject(): { [key: string]: T }
Converts keys to Strings.
Returns itself.
toSeq(): Seq.Set<T>
Returns a Seq.Keyed from this Collection where indices are treated as keys.
This is useful if you want to operate on a Collection and preserve the [value, value] pairs.
toKeyedSeq(): Seq.Keyed<T, T>
Returns an Seq.Indexed of the values of this Collection, discarding keys.
toIndexedSeq(): Seq.Indexed<T>
Returns a Seq.Set of the values of this Collection, discarding keys.
toSetSeq(): Seq.Set<T>
True if this and the other Collection have value equality, as defined by Immutable.is()
.
equals(other): boolean
Note: This is equivalent to Immutable.is(this, other)
, but provided to allow for chained expressions.
Computes and returns the hashed identity for this Collection.
The hashCode
of a Collection is used to determine potential equality, and is used when adding this to a Set
or as a key in a Map
, enabling lookup via a different instance.
hashCode(): number
If two values have the same hashCode
, they are not guaranteed to be equal. If two values have different hashCode
s, they must not be equal.
Returns the value associated with the provided key, or notSetValue if the Collection does not contain this key.
Note: it is possible a key may be associated with an undefined
value, so if notSetValue
is not provided and this method returns undefined
, that does not guarantee the key was not found.
get<NSV>(key: T, notSetValue: NSV): T | NSV
get(key: T): T | undefined
True if a key exists within this Collection, using Immutable.is
to determine equality.
has(key: T): boolean
True if a value exists within this Collection
, using Immutable.is
to determine equality.
includes(value: T): boolean
Returns the first value in this Collection.
first<NSV>(notSetValue: NSV): T | NSV
first(): T | undefined
Returns the last value in this Collection.
last<NSV>(notSetValue: NSV): T | NSV
last(): T | undefined
Returns the value found by following a path of keys or indices through nested Collections.
getIn(searchKeyPath: Iterable<unknown>, notSetValue?: unknown): unknown
Plain JavaScript Object or Arrays may be nested within an Immutable.js Collection, and getIn() can access those values as well:
True if the result of following a path of keys or indices through nested Collections results in a set value.
hasIn(searchKeyPath: Iterable<unknown>): boolean
Converts this Collection to a Map, Throws if keys are not hashable.
toMap(): Map<T, T>
Note: This is equivalent to Map(this.toKeyedSeq())
, but provided for convenience and to allow for chained expressions.
Converts this Collection to a Map, maintaining the order of iteration.
toOrderedMap(): OrderedMap<T, T>
Note: This is equivalent to OrderedMap(this.toKeyedSeq())
, but provided for convenience and to allow for chained expressions.
Returns itself.
toSet(): Set<T>
Converts this Collection to a Set, maintaining the order of iteration.
toOrderedSet(): OrderedSet<T>
Note: This is equivalent to OrderedSet(this)
, but provided for convenience and to allow for chained expressions.
Converts this Collection to a List.
toList(): List<T>
Converts this Collection to a Stack, discarding keys. Throws if values are not hashable.
toStack(): Stack<T>
Note: This is equivalent to Stack(this)
, but provided to allow for chained expressions.
An iterator of this Set
's keys.
keys(): IterableIterator<T>
Note: this will return an ES6 iterator which does not support Immutable.js sequence algorithms. Use keySeq
instead, if this is what you want.
An iterator of this Set
's values.
values(): IterableIterator<T>
Note: this will return an ES6 iterator which does not support Immutable.js sequence algorithms. Use valueSeq
instead, if this is what you want.
An iterator of this Set
's entries as [value, value]
tuples.
entries(): IterableIterator<[T, T]>
Note: this will return an ES6 iterator which does not support Immutable.js sequence algorithms. Use entrySeq
instead, if this is what you want.
Returns a new Seq.Indexed of the keys of this Collection, discarding values.
keySeq(): Seq.Indexed<T>
Returns an Seq.Indexed of the values of this Collection, discarding keys.
valueSeq(): Seq.Indexed<T>
Returns a new Seq.Indexed of [value, value] tuples.
entrySeq(): Seq.Indexed<[T, T]>
The sideEffect
is executed for every entry in the Collection.
forEach(sideEffect: (value: T, key: T, iter: this) => unknown, context?: unknown): number
Unlike Array#forEach
, if any call of sideEffect
returns false
, the iteration will stop. Returns the number of entries iterated (including the last iteration which returned false).
Returns a new Set of the same type representing a portion of this Set from start up to but not including end.
slice(begin?: number, end?: number): Set<T>
If begin is negative, it is offset from the end of the Collection. e.g. slice(-2)
returns a Collection of the last two entries. If it is not provided the new Collection will begin at the beginning of this Collection.
If end is negative, it is offset from the end of the Collection. e.g. slice(0, -1)
returns a Collection of everything but the last entry. If it is not provided, the new Collection will continue through the end of this Collection.
If the requested slice is equivalent to the current Collection, then it will return itself.
Returns a new Collection of the same type containing all entries except the first.
rest(): Set<T>
Returns a new Collection of the same type containing all entries except the last.
butLast(): Set<T>
Returns a new Collection of the same type which excludes the first amount
entries from this Collection.
skip(amount: number): Set<T>
Returns a new Collection of the same type which excludes the last amount
entries from this Collection.
skipLast(amount: number): Set<T>
Returns a new Collection of the same type which includes entries starting from when predicate
first returns false.
skipWhile(predicate: (value: T, key: T, iter: this) => boolean, context?: unknown): Set<T>
Returns a new Collection of the same type which includes entries starting from when predicate
first returns true.
skipUntil(predicate: (value: T, key: T, iter: this) => boolean, context?: unknown): Set<T>
Returns a new Collection of the same type which includes the first amount
entries from this Collection.
take(amount: number): Set<T>
Returns a new Collection of the same type which includes the last amount
entries from this Collection.
takeLast(amount: number): Set<T>
Returns a new Collection of the same type which includes entries from this Collection as long as the predicate
returns true.
takeWhile(predicate: (value: T, key: T, iter: this) => boolean, context?: unknown): Set<T>
Returns a new Collection of the same type which includes entries from this Collection as long as the predicate
returns false.
takeUntil(predicate: (value: T, key: T, iter: this) => boolean, context?: unknown): Set<T>
Returns a new Set with other collections concatenated to this one.
concat<C>(...valuesOrCollections: Array<Iterable<C> | C>): Set<T | C>
Flattens nested Collections.
Will deeply flatten the Collection by default, returning a Collection of the same type, but a depth
can be provided in the form of a number or boolean (where true means to shallowly flatten one level). A depth of 0 (or shallow: false) will deeply flatten.
Flattens only others Collection, not Arrays or Objects.
flatten(depth?: number): this
flatten(shallow?: boolean): this
Flat-maps the Set, returning a new Set.
Similar to set.map(...).flatten(true)
.
flatMap<M>(mapper: (value: T, key: T, iter: this) => Iterable<M>, context?: unknown): Set<M>
Reduces the Iterable to a value by calling the reducer
for every entry in the Iterable and passing along the reduced value.
reduce<R>(reducer: (reduced: R, value: T, key: T, iter: this) => R, initialValue: R): R
If initialValue is not provided, the first entry in the Iterable will be used as the initial value.
Reduces the Iterable to a value by calling the reducer
for every entry in the Iterable and passing along the reduced value.
reduceRight<R>(reducer: (reduced: R, value: T, key: T, iter: this) => R, initialValue: R): R
Note: Similar to this.reverse().reduce(), and provided for parity with Array#reduceRight
.
Returns true if the predicate
returns true for every entry in the Iterable.
every(predicate: (value: T, key: T, iter: this) => boolean, context?: unknown): boolean
Returns true if the predicate
returns true for any entry in the Iterable.
some(predicate: (value: T, key: T, iter: this) => boolean, context?: unknown): boolean
Returns a string of all the entries in the Iterable, separated by separator
.
join(separator?: string): string
Returns true if the Iterable is empty.
isEmpty(): boolean
Returns the number of entries in the Iterable.
count(): number
Returns a Map of the number of occurrences of each value in the Iterable.
countBy<G>(grouper: (value: T, key: T, iter: this) => G, context?: unknown): Map<G, number>
Returns the first value for which the predicate
returns true.
find(predicate: (value: T, key: T, iter: this) => boolean, context?: unknown, notSetValue?: T): T | undefined
Returns the last value for which the predicate
returns true.
findLast(predicate: (value: T, key: T, iter: this) => boolean, context?: unknown, notSetValue?: T): T | undefined
Note: predicate
will be called for each entry in reverse.
Returns the first [value, value] entry for which the predicate
returns true.
findEntry(predicate: (value: T, key: T, iter: this) => boolean, context?: unknown, notSetValue?: T): [T, T] | undefined
Returns the last [value, value] entry for which the predicate
returns true.
findLastEntry(predicate: (value: T, key: T, iter: this) => boolean, context?: unknown, notSetValue?: T): [T, T] | undefined
Note: predicate
will be called for each entry in reverse.
Returns the first key for which the predicate
returns true.
findKey(predicate: (value: T, key: T, iter: this) => boolean, context?: unknown): T | undefined
Returns the last key for which the predicate
returns true.
findLastKey(predicate: (value: T, key: T, iter: this) => boolean, context?: unknown): T | undefined
Note: predicate
will be called for each entry in reverse.
Returns the key associated with the search value, or undefined.
keyOf(searchValue: T): T | undefined
Returns the last key associated with the search value, or undefined.
lastKeyOf(searchValue: T): T | undefined
Returns the maximum value in this collection. If any values are comparatively equivalent, the first one found will be returned.
max(comparator?: Comparator<T>): T | undefined
The comparator is used in the same way as Collection#sort
. If it is not provided, the default comparator is >
.
When two values are considered equivalent, the first encountered will be returned. Otherwise, max
will operate independent of the order of input as long as the comparator is commutative. The default comparator >
is commutative only when types do not differ.
If comparator
returns 0 and either value is NaN, undefined, or null, that value will be returned.
Like max
, but also accepts a comparatorValueMapper
which allows for comparing by more sophisticated means:
maxBy<C>(comparatorValueMapper: (value: T, key: T, iter: this) => C, comparator?: Comparator<C>): T | undefined
Returns the minimum value in this collection. If any values are comparatively equivalent, the first one found will be returned.
min(comparator?: Comparator<T>): T | undefined
The comparator is used in the same way as Collection#sort
. If it is not provided, the default comparator is <
.
When two values are considered equivalent, the first encountered will be returned. Otherwise, min
will operate independent of the order of input as long as the comparator is commutative. The default comparator <
is commutative only when types do not differ.
If comparator
returns 0 and either value is NaN, undefined, or null, that value will be returned.
Like min
, but also accepts a comparatorValueMapper
which allows for comparing by more sophisticated means:
minBy<C>(comparatorValueMapper: (value: T, key: T, iter: this) => C, comparator?: Comparator<C>): T | undefined
True if iter
includes every value in this Collection.
isSubset(iter: Iterable<T>): boolean
True if this Collection includes every value in iter
.
isSuperset(iter: Iterable<T>): boolean