An iterator that never produces an element.
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A symbol with the same signature as this one exists in the latest stable release of Swift 6.1.
@frozen struct Iteratorimport Swift@frozen struct EmptyCollection<Element>A collection whose element type is Element but that is always empty.
init() Creates an instance.
var count: Int { get }The number of elements (always zero).
var endIndex: EmptyCollection<Element>.Index { get }Always zero, just like startIndex.
var startIndex: EmptyCollection<Element>.Index { get }Always zero, just like endIndex.
subscript(bounds: Range<EmptyCollection<Element>.Index>) -> EmptyCollection<Element>.SubSequence { get set } subscript(position: EmptyCollection<Element>.Index) -> Element { get set } Accesses the element at the given position.
static func == (lhs: EmptyCollection<Element>, rhs: EmptyCollection<Element>) -> Bool func distance(from start: EmptyCollection<Element>.Index, to end: EmptyCollection<Element>.Index) -> Int The distance between two indexes (always zero).
func index(_ i: EmptyCollection<Element>.Index, offsetBy n: Int) -> EmptyCollection<Element>.Index func index(_ i: EmptyCollection<Element>.Index, offsetBy n: Int, limitedBy limit: EmptyCollection<Element>.Index) -> EmptyCollection<Element>.Index? func index(after i: EmptyCollection<Element>.Index) -> EmptyCollection<Element>.Index Always traps.
func index(before i: EmptyCollection<Element>.Index) -> EmptyCollection<Element>.Index Always traps.
func makeIterator() -> EmptyCollection<Element>.Iterator Returns an empty iterator.
typealias Index = IntA type that represents a valid position in the collection.
typealias Indices = Range<Int>typealias SubSequence = EmptyCollection<Element>protocol BitwiseCopyableinit() Creates an instance.
mutating func next() -> Element? Returns nil, indicating that there are no more elements.
protocol CopyableA type whose values can be implicitly or explicitly copied.
protocol Escapableprotocol IteratorProtocol<Element>A type that supplies the values of a sequence one at a time.
protocol Sendableprotocol Sequence<Element>A type that provides sequential, iterated access to its elements.
var lazy: LazySequence<Self> { get }A sequence containing the same elements as this sequence, but on which some operations, such as map and filter, are implemented lazily.
var underestimatedCount: Int { get }A value less than or equal to the number of elements in the sequence, calculated nondestructively.
func allSatisfy(_ predicate: (Self.Element) throws -> Bool) rethrows -> Bool Returns a Boolean value indicating whether every element of a sequence satisfies a given predicate.
func compactMap<ElementOfResult>(_ transform: (Self.Element) throws -> ElementOfResult?) rethrows -> [ElementOfResult] Returns an array containing the non-nil results of calling the given transformation with each element of this sequence.
func contains(_ element: Self.Element) -> Bool Returns a Boolean value indicating whether the sequence contains the given element.
func contains(where predicate: (Self.Element) throws -> Bool) rethrows -> Bool Returns a Boolean value indicating whether the sequence contains an element that satisfies the given predicate.
func count<E>(where predicate: (Self.Element) throws(E) -> Bool) throws(E) -> Int where E : Error Returns the number of elements in the sequence that satisfy the given predicate.
func drop(while predicate: (Self.Element) throws -> Bool) rethrows -> DropWhileSequence<Self> Returns a sequence by skipping the initial, consecutive elements that satisfy the given predicate.
func dropFirst(_ k: Int = 1) -> DropFirstSequence<Self> Returns a sequence containing all but the given number of initial elements.
func dropLast(_ k: Int = 1) -> [Self.Element] Returns a sequence containing all but the given number of final elements.
func elementsEqual<OtherSequence>(_ other: OtherSequence) -> Bool where OtherSequence : Sequence, Self.Element == OtherSequence.Element Returns a Boolean value indicating whether this sequence and another sequence contain the same elements in the same order.
func elementsEqual<OtherSequence>(_ other: OtherSequence, by areEquivalent: (Self.Element, OtherSequence.Element) throws -> Bool) rethrows -> Bool where OtherSequence : Sequence 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<Self> 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 filter(_ isIncluded: (Self.Element) throws -> Bool) rethrows -> [Self.Element] Returns an array containing, in order, the elements of the sequence that satisfy the given predicate.
func first(where predicate: (Self.Element) throws -> Bool) rethrows -> Self.Element? Returns the first element of the sequence that satisfies the given predicate.
func flatMap<SegmentOfResult>(_ transform: (Self.Element) throws -> SegmentOfResult) rethrows -> [SegmentOfResult.Element] where SegmentOfResult : Sequence Returns an array containing the concatenated results of calling the given transformation with each element of this sequence.
func forEach(_ body: (Self.Element) throws -> Void) rethrows Calls the given closure on each element in the sequence in the same order as a for-in loop.
func joined() -> FlattenSequence<Self> Returns the elements of this sequence of sequences, concatenated.
func joined<Separator>(separator: Separator) -> JoinedSequence<Self> where Separator : Sequence, Separator.Element == Self.Element.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>(_ other: OtherSequence) -> Bool where OtherSequence : Sequence, Self.Element == OtherSequence.Element 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>(_ other: OtherSequence, by areInIncreasingOrder: (Self.Element, Self.Element) throws -> Bool) rethrows -> Bool where OtherSequence : Sequence, Self.Element == OtherSequence.Element 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() -> Self Returns an iterator over the elements of this sequence.
func map<T, E>(_ transform: (Self.Element) throws(E) -> T) throws(E) -> [T] where E : Error Returns an array containing the results of mapping the given closure over the sequence’s elements.
@warn_unqualified_access func max() -> Self.Element? Returns the maximum element in the sequence.
@warn_unqualified_access func max(by areInIncreasingOrder: (Self.Element, Self.Element) throws -> Bool) rethrows -> Self.Element? Returns the maximum element in the sequence, using the given predicate as the comparison between elements.
@warn_unqualified_access func min() -> Self.Element? Returns the minimum element in the sequence.
@warn_unqualified_access func min(by areInIncreasingOrder: (Self.Element, Self.Element) throws -> Bool) rethrows -> Self.Element? Returns the minimum element in the sequence, using the given predicate as the comparison between elements.
func prefix(_ maxLength: Int) -> PrefixSequence<Self> Returns a sequence, up to the specified maximum length, containing the initial elements of the sequence.
func prefix(while predicate: (Self.Element) throws -> Bool) rethrows -> [Self.Element] Returns a sequence containing the initial, consecutive elements that satisfy the given predicate.
func reduce<Result>(_ initialResult: Result, _ nextPartialResult: (Result, Self.Element) throws -> Result) rethrows -> Result Returns the result of combining the elements of the sequence using the given closure.
func reduce<Result>(into initialResult: Result, _ updateAccumulatingResult: (inout Result, Self.Element) throws -> ()) rethrows -> Result Returns the result of combining the elements of the sequence using the given closure.
func reversed() -> [Self.Element] Returns an array containing the elements of this sequence in reverse order.
func shuffled() -> [Self.Element] Returns the elements of the sequence, shuffled.
func shuffled<T>(using generator: inout T) -> [Self.Element] where T : RandomNumberGenerator Returns the elements of the sequence, shuffled using the given generator as a source for randomness.
func sorted() -> [Self.Element] Returns the elements of the sequence, sorted.
func sorted(by areInIncreasingOrder: (Self.Element, Self.Element) throws -> Bool) rethrows -> [Self.Element] Returns the elements of the sequence, sorted using the given predicate as the comparison between elements.
func split(maxSplits: Int = Int.max, omittingEmptySubsequences: Bool = true, whereSeparator isSeparator: (Self.Element) throws -> Bool) rethrows -> [ArraySlice<Self.Element>] Returns the longest possible subsequences of the sequence, in order, that don’t contain elements satisfying the given predicate. Elements that are used to split the sequence are not returned as part of any subsequence.
func split(separator: Self.Element, maxSplits: Int = Int.max, omittingEmptySubsequences: Bool = true) -> [ArraySlice<Self.Element>] Returns the longest possible subsequences of the sequence, in order, around elements equal to the given element.
func starts<PossiblePrefix>(with possiblePrefix: PossiblePrefix) -> Bool where PossiblePrefix : Sequence, Self.Element == PossiblePrefix.Element 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: PossiblePrefix, by areEquivalent: (Self.Element, PossiblePrefix.Element) throws -> Bool) rethrows -> Bool where PossiblePrefix : Sequence 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.
func suffix(_ maxLength: Int) -> [Self.Element] Returns a subsequence, up to the given maximum length, containing the final elements of the sequence.
func withContiguousStorageIfAvailable<R>(_ body: (UnsafeBufferPointer<Self.Element>) throws -> R) rethrows -> R? func flatMap<ElementOfResult>(_ transform: (Self.Element) throws -> ElementOfResult?) rethrows -> [ElementOfResult]