An iterator over the elements traversed by some base iterator that also satisfy a given predicate.
SDK
- Xcode 10.0+
Framework
- Swift Standard Library
Declaration
@frozen struct Iterator
StructureLazy
Lazy
Topics
Type Aliases
typealias LazyThe type of element traversed by the iterator.
typealias LazyA type that provides the sequence’s iteration interface and encapsulates its iteration state.
Instance Properties
var base: BaseThe underlying iterator whose elements are being filtered.
var lazy: LazyA sequence containing the same elements as this sequence, but on which some operations, such as map and filter, are implemented lazily.
var underestimatedA value less than or equal to the number of elements in the sequence, calculated nondestructively.
Instance Methods
func allReturns a Boolean value indicating whether every element of a sequence satisfies a given predicate.
func compactReturns an array containing the non-nil results of calling the given transformation with each element of this sequence.
func contains(BaseReturns a Boolean value indicating whether the sequence contains the given element.
func contains(where: (BaseReturns a Boolean value indicating whether the sequence contains an element that satisfies the given predicate.
func drop(while: (BaseReturns a sequence by skipping the initial, consecutive elements that satisfy the given predicate.
func dropReturns a sequence containing all but the given number of initial elements.
func dropReturns a sequence containing all but the given number of final elements.
func elementsReturns a Boolean value indicating whether this sequence and another sequence contain the same elements in the same order.
func elementsReturns 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() -> EnumeratedReturns 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((BaseReturns an array containing, in order, the elements of the sequence that satisfy the given predicate.
func first(where: (BaseReturns the first element of the sequence that satisfies the given predicate.
func flatReturns an array containing the concatenated results of calling the given transformation with each element of this sequence.
func flatReturns an array containing the non-nil results of calling the given transformation with each element of this sequence.
func forCalls the given closure on each element in the sequence in the same order as a for-in loop.
func joined() -> FlattenReturns the elements of this sequence of sequences, concatenated.
func joined(separator: String) -> StringReturns a new string by concatenating the elements of the sequence, adding the given separator between each element.
func joined<Separator>(separator: Separator) -> JoinedReturns the concatenated elements of this sequence of sequences, inserting the given separator between each element.
func lexicographicallyReturns a Boolean value indicating whether the sequence precedes another sequence in a lexicographical (dictionary) ordering, using the less-than operator (<) to compare elements.
func lexicographicallyReturns a Boolean value indicating whether the sequence precedes another sequence in a lexicographical (dictionary) ordering, using the given predicate to compare elements.
func makeReturns an iterator over the elements of this sequence.
func map<T>((BaseReturns an array containing the results of mapping the given closure over the sequence’s elements.
func max() -> BaseReturns the maximum element in the sequence.
func max(by: (BaseReturns the maximum element in the sequence, using the given predicate as the comparison between elements.
func min() -> BaseReturns the minimum element in the sequence.
func min(by: (BaseReturns the minimum element in the sequence, using the given predicate as the comparison between elements.
func next() -> LazyAdvances to the next element and returns it, or nil if no next element exists.
func prefix(Int) -> PrefixReturns a sequence, up to the specified maximum length, containing the initial elements of the sequence.
func prefix(while: (BaseReturns a sequence containing the initial, consecutive elements that satisfy the given predicate.
func reduce<Result>(Result, (Result, BaseReturns the result of combining the elements of the sequence using the given closure.
func reduce<Result>(into: Result, (inout Result, BaseReturns the result of combining the elements of the sequence using the given closure.
func reversed() -> [BaseReturns an array containing the elements of this sequence in reverse order.
func shuffled() -> [BaseReturns the elements of the sequence, shuffled.
func shuffled<T>(using: inout T) -> [BaseReturns the elements of the sequence, shuffled using the given generator as a source for randomness.
func sorted() -> [BaseReturns the elements of the sequence, sorted.
func sorted(by: (BaseReturns the elements of the sequence, sorted using the given predicate as the comparison between elements.
func split(maxReturns 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: BaseReturns the longest possible subsequences of the sequence, in order, around elements equal to the given element.
func starts<PossibleReturns a Boolean value indicating whether the initial elements of the sequence are the same as the elements in another sequence.
func starts<PossibleReturns 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(Int) -> [BaseReturns a subsequence, up to the given maximum length, containing the final elements of the sequence.
func withCall body(p), where p is a pointer to the collection’s contiguous storage. If no such storage exists, it is first created. If the collection does not support an internal representation in a form of contiguous storage, body is not called and nil is returned.