Order Dependent Operations on Set

Perform order-dependent operations common to all collections, as implemented for Set.

Topics

Manipulating Indices

var startIndex: Set<Element>.Index

The starting position for iterating members of the set.

var endIndex: Set<Element>.Index

The “past the end” position for the set—that is, the position one greater than the last valid subscript argument.

func formIndex(after: inout Set<Element>.Index)

Replaces the given index with its successor.

func index(Set<Element>.Index, offsetBy: Int) -> Set<Element>.Index

Returns an index that is the specified distance from the given index.

func formIndex(inout Set<Element>.Index, offsetBy: Int)

Offsets the given index by the specified distance.

func index(Set<Element>.Index, offsetBy: Int, limitedBy: Set<Element>.Index) -> Set<Element>.Index?

Returns an index that is the specified distance from the given index, unless that distance is beyond a given limiting index.

func formIndex(inout Set<Element>.Index, offsetBy: Int, limitedBy: Set<Element>.Index) -> Bool

Offsets the given index by the specified distance, or so that it equals the given limiting index.

var indices: DefaultIndices<Set<Element>>

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

Comparing Sets

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 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 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

Selecting Elements

subscript(Range<Set<Element>.Index>) -> Slice<Set<Element>>

Accesses a contiguous subrange of the collection’s elements.

subscript<R>(R) -> Slice<Set<Element>>

Accesses the contiguous subrange of the collection’s elements specified by a range expression.

func prefix(Int) -> Slice<Set<Element>>

Returns a subsequence, up to the specified maximum length, containing the initial elements of the collection.

func prefix(upTo: Set<Element>.Index) -> Slice<Set<Element>>

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

func prefix(through: Set<Element>.Index) -> Slice<Set<Element>>

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

func prefix(while: (Element) -> Bool) -> Slice<Set<Element>>

Returns a subsequence containing the initial elements until predicate returns false and skipping the remaining elements.

func suffix(Int) -> Slice<Set<Element>>

Returns a subsequence, up to the given maximum length, containing the final elements of the collection.

func suffix(from: Set<Element>.Index) -> Slice<Set<Element>>

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

Excluding Elements

func drop(while: (Element) -> Bool) -> Slice<Set<Element>>

Returns a subsequence by skipping elements while predicate returns true and returning the remaining elements.

func dropFirst() -> Slice<Set<Element>>

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

func dropFirst(Int) -> Slice<Set<Element>>

Returns a subsequence containing all but the given number of initial elements.

func dropLast() -> Slice<Set<Element>>

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

func dropLast(Int) -> Slice<Set<Element>>

Returns a subsequence containing all but the specified number of final elements.

func popFirst() -> Set<Element>.Element?

Removes and returns the first element of the set.

Reversing a Set's Elements

func reversed() -> [Element]

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

Splitting and Joining Elements

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

Returns the elements of this collection of collections, concatenated.

func joined() -> FlattenSequence<Set<Element>>

Returns the elements of this sequence of sequences, concatenated.

func joined<Separator>(separator: Separator) -> JoinedSequence<Set<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 split(separator: Element, maxSplits: Int, omittingEmptySubsequences: Bool) -> [Slice<Set<Element>>]

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

func split(maxSplits: Int, omittingEmptySubsequences: Bool, whereSeparator: (Element) -> Bool) -> [Slice<Set<Element>>]

Returns the longest possible subsequences of the collection, in order, that don’t contain elements satisfying the given predicate.

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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