Generic Structure

AnyCollection

A type-erased wrapper over any collection with indices that support forward traversal.

Overview

An AnyCollection instance forwards its operations to a base collection having the same Element type, hiding the specifics of the underlying collection.

Topics

Initializers

init(AnyCollection<AnyCollection<Element>.Element>)

Creates an AnyCollection having the same underlying collection as other.

init(AnyRandomAccessCollection<AnyCollection<Element>.Element>)

Creates an AnyCollection having the same underlying collection as other.

init(AnyBidirectionalCollection<AnyCollection<Element>.Element>)

Creates an AnyCollection having the same underlying collection as other.

init<C>(C)

Creates a type-erased collection that wraps the given collection.

init<C>(C)

Creates a type-erased collection that wraps the given collection.

init<C>(C)

Creates a type-erased collection that wraps the given collection.

Instance Properties

var count: Int

The number of elements in the collection.

var count: Int

The number of elements.

var endIndex: AnyCollection<Element>.Index

The collection’s “past the end” position—that is, the position one greater than the last valid subscript argument.

var first: Element?

The first element of the collection.

var indices: DefaultIndices<AnyCollection<Element>>

The indices that are valid for subscripting the collection, in ascending order.

var isEmpty: Bool

A Boolean value indicating whether the collection is empty.

var lazy: LazyCollection<AnyCollection<Element>>

A view onto this collection that provides lazy implementations of normally eager operations, such as map and filter.

var lazy: LazySequence<AnyCollection<Element>>

A sequence containing the same elements as this sequence, but on which some operations, such as map and filter, are implemented lazily.

var startIndex: AnyCollection<Element>.Index

The position of the first element in a non-empty collection.

var underestimatedCount: Int

A value less than or equal to the number of elements in the collection.

var underestimatedCount: Int

A value less than or equal to the number of elements in the sequence, calculated nondestructively.

Instance Methods

func allSatisfy((Element) -> Bool) -> Bool

Returns a Boolean value indicating whether every element of a sequence satisfies a given predicate.

Beta
func compactMap<ElementOfResult>((Element) -> ElementOfResult?) -> [ElementOfResult]

Returns an array containing the non-nil results of calling the given transformation with each element of this sequence.

func contains(Element) -> Bool

Returns a Boolean value indicating whether the sequence contains the given element.

func contains(where: (Element) -> Bool) -> Bool

Returns a Boolean value indicating whether the sequence contains an element that satisfies the given predicate.

func dropFirst() -> AnyCollection<Element>

Returns a subsequence containing all but the first element of the sequence.

func dropLast() -> AnyCollection<Element>

Returns a subsequence containing all but the last element of the sequence.

func elementsEqual<OtherSequence>(OtherSequence) -> Bool

Returns a Boolean value indicating whether this sequence and another sequence contain the same elements in the same order.

func elementsEqual<OtherSequence>(OtherSequence, by: (Element, OtherSequence.Element) -> Bool) -> Bool

Returns a Boolean value indicating whether this sequence and another sequence contain equivalent elements in the same order, using the given predicate as the equivalence test.

func enumerated() -> EnumeratedSequence<AnyCollection<Element>>

Returns a sequence of pairs (n, x), where n represents a consecutive integer starting at zero and x represents an element of the sequence.

func first(where: (Element) -> Bool) -> Element?

Returns the first element of the sequence that satisfies the given predicate.

func firstIndex(of: Element) -> AnyIndex?

Returns the first index where the specified value appears in the collection.

Beta
func firstIndex(where: (Element) -> Bool) -> AnyIndex?

Returns the first index in which an element of the collection satisfies the given predicate.

Beta
func joined() -> FlattenSequence<AnyCollection<Element>>

Returns the elements of this sequence of sequences, concatenated.

func joined() -> FlattenCollection<AnyCollection<Element>>

Returns the elements of this collection of collections, concatenated.

func joined<Separator>(separator: Separator) -> JoinedSequence<AnyCollection<Element>>

Returns the concatenated elements of this sequence of sequences, inserting the given separator between each element.

func joined(separator: String) -> String

Returns a new string by concatenating the elements of the sequence, adding the given separator between each element.

func lexicographicallyPrecedes<OtherSequence>(OtherSequence) -> Bool

Returns a Boolean value indicating whether the sequence precedes another sequence in a lexicographical (dictionary) ordering, using the less-than operator (<) to compare elements.

func lexicographicallyPrecedes<OtherSequence>(OtherSequence, by: (Element, Element) -> Bool) -> Bool

Returns a Boolean value indicating whether the sequence precedes another sequence in a lexicographical (dictionary) ordering, using the given predicate to compare elements.

func makeIterator() -> AnyCollection<Element>.Iterator

Returns an iterator over the elements of this collection.

func map<T>((Element) -> T) -> [T]

Returns an array containing the results of mapping the given closure over the sequence’s elements.

func map<T>((Element) -> T) -> [T]

Returns an array containing the results of mapping the given closure over the sequence’s elements.

func max() -> Element?

Returns the maximum element in the sequence.

func max(by: (Element, Element) -> Bool) -> Element?

Returns the maximum element in the sequence, using the given predicate as the comparison between elements.

func min() -> Element?

Returns the minimum element in the sequence.

func min(by: (Element, Element) -> Bool) -> Element?

Returns the minimum element in the sequence, using the given predicate as the comparison between elements.

func popFirst() -> Element?

Removes and returns the first element of the collection.

func prefix(through: AnyIndex) -> AnyCollection<Element>

Returns a subsequence from the start of the collection through the specified position.

func prefix(upTo: AnyIndex) -> AnyCollection<Element>

Returns a subsequence from the start of the collection up to, but not including, the specified position.

func randomElement() -> Element?

Returns a random element of the collection.

Beta
func randomElement<T>(using: inout T) -> Element?

Returns a random element of the collection, using the given generator as a source for randomness.

Beta
func reduce<Result>(Result, (Result, Element) -> Result) -> Result

Returns the result of combining the elements of the sequence using the given closure.

func reduce<Result>(into: Result, (inout Result, Element) -> ()) -> Result

Returns the result of combining the elements of the sequence using the given closure.

func removeFirst() -> Element

Removes and returns the first element of the collection.

func removeFirst(Int)

Removes the specified number of elements from the beginning of the collection.

func reversed() -> [Element]

Returns an array containing the elements of this sequence in reverse order.

func shuffled() -> [Element]

Returns the elements of the sequence, shuffled.

Beta
func shuffled<T>(using: inout T) -> [Element]

Returns the elements of the sequence, shuffled using the given generator as a source for randomness.

Beta
func sorted() -> [Element]

Returns the elements of the sequence, sorted.

func sorted(by: (Element, Element) -> Bool) -> [Element]

Returns the elements of the sequence, sorted using the given predicate as the comparison between elements.

func split(separator: Element, maxSplits: Int, omittingEmptySubsequences: Bool) -> [AnyCollection<Element>]

Returns the longest possible subsequences of the sequence, in order, around elements equal to the given element.

func split(separator: Element, maxSplits: Int, omittingEmptySubsequences: Bool) -> [AnyCollection<Element>]

Returns the longest possible subsequences of the collection, in order, around elements equal to the given element.

func starts<PossiblePrefix>(with: PossiblePrefix) -> Bool

Returns a Boolean value indicating whether the initial elements of the sequence are the same as the elements in another sequence.

func starts<PossiblePrefix>(with: PossiblePrefix, by: (Element, PossiblePrefix.Element) -> Bool) -> Bool

Returns a Boolean value indicating whether the initial elements of the sequence are equivalent to the elements in another sequence, using the given predicate as the equivalence test.

Beta
func suffix(from: AnyIndex) -> AnyCollection<Element>

Returns a subsequence from the specified position to the end of the collection.

Relationships

Conforms To

See Also

Type-Erasing Wrappers

struct AnyBidirectionalCollection

A type-erased wrapper over any collection with indices that support bidirectional traversal.

struct AnyRandomAccessCollection

A type-erased wrapper over any collection with indices that support random access traversal.

struct AnyIterator

A type-erased iterator of Element.

struct AnyIndex

A wrapper over an underlying index that hides the specific underlying type.

struct AnyHashable

A type-erased hashable value.

Beta Software

This documentation contains preliminary information about an API or technology in development. This information is subject to change, and software implemented according to this documentation should be tested with final operating system software.

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