struct String.CharacterView A String's collection of Characters (extended grapheme clusters) elements. Inheritance CollectionType, Indexable, RangeReplaceableCollectionType, SequenceType View Protocol Hierarchy → Associated Types Generator = IndexingGenerator<String.CharacterView> Type alias inferred. Element = Character Type alias inferred. Index = String.CharacterView.Index Type alias inferred. SubSequence = String.CharacterView Type alias inferred. Nested Types String.CharacterView.Index Import import Swift Initializers init() Create an empty instance. Declaration init() init(_: String) Create a view of the Characters in text. Declaration init(_ text: String) init<S : SequenceType where S.Generator.Element == Character>(_: S) Create an instance containing characters. Declaration init<S : SequenceType where S.Generator.Element == Character>(_ characters: S) init(_:) Creates a collection instance that contains elements. Declaration init<S : SequenceType where S.Generator.Element == Generator.Element>(_ elements: S) Declared In RangeReplaceableCollectionType Instance Variables var count: String.CharacterView.Index.Distance Returns the number of elements. Complexity: O(1) if Index conforms to RandomAccessIndexType; O(N) otherwise. Declaration var count: String.CharacterView.Index.Distance { get } Declared In RangeReplaceableCollectionType , CollectionType var endIndex: String.CharacterView.Index The "past the end" position. endIndex is not a valid argument to subscript, and is always reachable from startIndex by zero or more applications of successor(). Declaration var endIndex: String.CharacterView.Index { get } var first: Character? Returns the first element of self, or nil if self is empty. Complexity: O(1) Declaration var first: Character? { get } Declared In RangeReplaceableCollectionType , CollectionType var indices: Range<String.CharacterView.Index> Returns the range of valid index values. The result's endIndex is the same as that of self. Because Range is half-open, iterating the values of the result produces all valid subscript arguments for self, omitting its endIndex. Declaration var indices: Range<String.CharacterView.Index> { get } Declared In RangeReplaceableCollectionType , CollectionType var isEmpty: Bool Returns true iff self is empty. Complexity: O(1) Declaration var isEmpty: Bool { get } Declared In RangeReplaceableCollectionType , CollectionType var last: Character? Declaration var last: Character? { get } Declared In RangeReplaceableCollectionType , CollectionType var lazy: LazyCollection<String.CharacterView> A collection with contents identical to self, but on which normally-eager operations such as map and filter are implemented lazily. See Also: LazySequenceType, LazyCollectionType. Declaration var lazy: LazyCollection<String.CharacterView> { get } Declared In RangeReplaceableCollectionType , CollectionType var startIndex: String.CharacterView.Index The position of the first Character if self is non-empty; identical to endIndex otherwise. Declaration var startIndex: String.CharacterView.Index { get } Subscripts subscript(_: Range<String.CharacterView.Index>) Access the characters in the given subRange. Complexity: O(1) unless bridging from Objective-C requires an O(N) conversion. Declaration subscript(subRange: Range<String.CharacterView.Index>) -> String.CharacterView { get } subscript(_: String.CharacterView.Index) Access the Character at position. Requires: position is a valid position in self and position != endIndex. Declaration subscript(i: String.CharacterView.Index) -> Character { get } Instance Methods mutating func append(_:) Append c to self. Complexity: Amortized O(1). Declaration mutating func append(c: Character) Declared In String.CharacterView, RangeReplaceableCollectionType mutating func appendContentsOf(_:) Append the elements of newElements to self. Declaration mutating func appendContentsOf<S : SequenceType where S.Generator.Element == Character>(newElements: S) Declared In String.CharacterView, RangeReplaceableCollectionType func contains(_:) Returns true iff an element in self satisfies predicate. Declaration func contains(@noescape predicate: (Character) throws -> Bool) rethrows -> Bool Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func dropFirst() Returns a subsequence containing all but the first element. Complexity: O(1) Declaration func dropFirst() -> String.CharacterView Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func dropFirst(_:) Returns a subsequence containing all but the first n elements. Requires: n >= 0 Complexity: O(n) Declaration func dropFirst(n: Int) -> String.CharacterView Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func dropLast() Returns a subsequence containing all but the last element. Requires: self is a finite sequence. Complexity: O(self.count) Declaration func dropLast() -> String.CharacterView Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func dropLast(_:) Returns a subsequence containing all but the last n elements. Requires: n >= 0 Complexity: O(self.count) Declaration func dropLast(n: Int) -> String.CharacterView Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func elementsEqual(_:) Returns true iff self and other contain the same elements in the same order. Declaration func elementsEqual<OtherSequence : SequenceType where OtherSequence.Generator.Element == Generator.Element>(other: OtherSequence) -> Bool Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func elementsEqual(_:isEquivalent:) Returns true iff self and other contain equivalent elements, using isEquivalent as the equivalence test. Requires: isEquivalent is an equivalence relation. Declaration func elementsEqual<OtherSequence : SequenceType where OtherSequence.Generator.Element == Generator.Element>(other: OtherSequence, @noescape isEquivalent: (Character, Character) throws -> Bool) rethrows -> Bool Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func enumerate() Returns a lazy SequenceType containing pairs (n, x), where ns are consecutive Ints starting at zero, and xs are the elements of base: > for (n, c) in "Swift".characters.enumerate() { print("\(n): '\(c)'") } 0: 'S' 1: 'w' 2: 'i' 3: 'f' 4: 't' Declaration func enumerate() -> EnumerateSequence<String.CharacterView> Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func filter(_:) Returns an Array containing the elements of self, in order, that satisfy the predicate includeElement. Declaration func filter(@noescape includeElement: (Character) throws -> Bool) rethrows -> [Character] Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func flatMap<T>(_: (Character) throws -> T?) Returns an Array containing the non-nil results of mapping transform over self. Complexity: O(M + N), where M is the length of self and N is the length of the result. Declaration func flatMap<T>(@noescape transform: (Character) throws -> T?) rethrows -> [T] Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func flatMap<S : SequenceType>(_: (Character) throws -> S) Returns an Array containing the concatenated results of mapping transform over self. s.flatMap(transform) is equivalent to Array(s.map(transform).flatten()) Complexity: O(M + N), where M is the length of self and N is the length of the result. Declaration func flatMap<S : SequenceType>(transform: (Character) throws -> S) rethrows -> [S.Generator.Element] Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func forEach(_:) Call body on each element in self in the same order as a for-in loop. sequence.forEach { // body code } is similar to: for element in sequence { // body code } Note: You cannot use the break or continue statement to exit the current call of the body closure or skip subsequent calls. Note: Using the return statement in the body closure will only exit from the current call to body, not any outer scope, and won't skip subsequent calls. Complexity: O(self.count) Declaration func forEach(@noescape body: (Character) throws -> Void) rethrows Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func generate() Declaration func generate() -> IndexingGenerator<String.CharacterView> Declared In RangeReplaceableCollectionType, CollectionType func indexOf(_:) Returns the first index where predicate returns true for the corresponding value, or nil if such value is not found. Complexity: O(self.count). Declaration func indexOf(@noescape predicate: (Character) throws -> Bool) rethrows -> String.CharacterView.Index? Declared In RangeReplaceableCollectionType, CollectionType mutating func insert(_:atIndex:) Insert newElement at index i. Invalidates all indices with respect to self. Complexity: O(self.count). Declaration mutating func insert(newElement: Character, atIndex i: String.CharacterView.Index) Declared In RangeReplaceableCollectionType mutating func insertContentsOf(_:at:) Insert newElements at index i. Invalidates all indices with respect to self. Complexity: O(self.count + newElements.count). Declaration mutating func insertContentsOf<C : CollectionType where C.Generator.Element == Generator.Element>(newElements: C, at i: String.CharacterView.Index) Declared In RangeReplaceableCollectionType func lexicographicalCompare(_:) Returns true iff self precedes other in a lexicographical ("dictionary") ordering, using "<" as the comparison between elements. Note: This method implements the mathematical notion of lexicographical ordering, which has no connection to Unicode. If you are sorting strings to present to the end-user, you should use String APIs that perform localized comparison. Declaration func lexicographicalCompare<OtherSequence : SequenceType where OtherSequence.Generator.Element == Generator.Element>(other: OtherSequence) -> Bool Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func lexicographicalCompare(_:isOrderedBefore:) Returns true iff self precedes other in a lexicographical ("dictionary") ordering, using isOrderedBefore as the comparison between elements. Note: This method implements the mathematical notion of lexicographical ordering, which has no connection to Unicode. If you are sorting strings to present to the end-user, you should use String APIs that perform localized comparison. Requires: isOrderedBefore is a strict weak ordering over the elements of self and other. Declaration func lexicographicalCompare<OtherSequence : SequenceType where OtherSequence.Generator.Element == Generator.Element>(other: OtherSequence, @noescape isOrderedBefore: (Character, Character) throws -> Bool) rethrows -> Bool Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func map(_:) Returns an Array containing the results of mapping transform over self. Complexity: O(N). Declaration func map<T>(@noescape transform: (Character) throws -> T) rethrows -> [T] Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func maxElement() Returns the maximum element in self or nil if the sequence is empty. Complexity: O(elements.count). Declaration func maxElement() -> Character? Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func maxElement(_:) Returns the maximum element in self or nil if the sequence is empty. Complexity: O(elements.count). Requires: isOrderedBefore is a strict weak ordering over self. Declaration func maxElement(@noescape isOrderedBefore: (Character, Character) throws -> Bool) rethrows -> Character? Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func minElement() Returns the minimum element in self or nil if the sequence is empty. Complexity: O(elements.count). Declaration func minElement() -> Character? Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func minElement(_:) Returns the minimum element in self or nil if the sequence is empty. Complexity: O(elements.count). Requires: isOrderedBefore is a strict weak ordering over self. Declaration func minElement(@noescape isOrderedBefore: (Character, Character) throws -> Bool) rethrows -> Character? Declared In RangeReplaceableCollectionType, CollectionType, SequenceType mutating func popFirst() If !self.isEmpty, remove the first element and return it, otherwise return nil. Complexity: O(1) Declaration mutating func popFirst() -> Character? Declared In RangeReplaceableCollectionType, CollectionType mutating func popLast() If !self.isEmpty, remove the last element and return it, otherwise return nil. Complexity: O(self.count) Deprecated: it will be removed in Swift 3. Declaration mutating func popLast() -> Character? Declared In RangeReplaceableCollectionType, CollectionType func prefix(_:) Returns a subsequence, up to maxLength in length, containing the initial elements. If maxLength exceeds self.count, the result contains all the elements of self. Requires: maxLength >= 0 Complexity: O(maxLength) Declaration func prefix(maxLength: Int) -> String.CharacterView Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func prefixThrough(_:) Returns prefixUpTo(position.successor()) Complexity: O(1) Declaration func prefixThrough(position: String.CharacterView.Index) -> String.CharacterView Declared In RangeReplaceableCollectionType, CollectionType func prefixUpTo(_:) Returns self[startIndex..<end] Complexity: O(1) Declaration func prefixUpTo(end: String.CharacterView.Index) -> String.CharacterView Declared In RangeReplaceableCollectionType, CollectionType func reduce(_:combine:) Returns the result of repeatedly calling combine with an accumulated value initialized to initial and each element of self, in turn, i.e. return combine(combine(...combine(combine(initial, self[0]), self[1]),...self[count-2]), self[count-1]). Declaration func reduce<T>(initial: T, @noescape combine: (T, Character) throws -> T) rethrows -> T Declared In RangeReplaceableCollectionType, CollectionType, SequenceType mutating func removeAll(keepCapacity:) Remove all elements. Invalidates all indices with respect to self. keepCapacity: If true, is a non-binding request to avoid releasing storage, which can be a useful optimization when self is going to be grown again. Complexity: O(self.count). Declaration mutating func removeAll(keepCapacity keepCapacity: Bool = default) Declared In RangeReplaceableCollectionType mutating func removeAtIndex(_:) Remove the element at index i. Invalidates all indices with respect to self. Complexity: O(self.count). Declaration mutating func removeAtIndex(index: String.CharacterView.Index) -> Character Declared In RangeReplaceableCollectionType mutating func removeFirst() Remove the element at startIndex and return it. Complexity: O(self.count) Requires: !self.isEmpty. Declaration mutating func removeFirst() -> Character Declared In RangeReplaceableCollectionType, CollectionType mutating func removeFirst(_:) Remove the first n elements. Complexity: O(self.count) Requires: n >= 0 && self.count >= n. Declaration mutating func removeFirst(n: Int) Declared In RangeReplaceableCollectionType, CollectionType mutating func removeLast() Remove an element from the end. Complexity: O(1) Requires: !self.isEmpty Declaration mutating func removeLast() -> Character Declared In RangeReplaceableCollectionType, CollectionType mutating func removeLast(_:) Remove the last n elements. Complexity: O(self.count) Requires: n >= 0 && self.count >= n. Declaration mutating func removeLast(n: Int) Declared In RangeReplaceableCollectionType, CollectionType mutating func removeRange(_:) Remove the indicated subRange of elements. Invalidates all indices with respect to self. Complexity: O(self.count). Declaration mutating func removeRange(subRange: Range<String.CharacterView.Index>) Declared In RangeReplaceableCollectionType mutating func replaceRange(_:with:) Replace the given subRange of elements with newElements. Invalidates all indices with respect to self. Complexity: O(subRange.count) if subRange.endIndex == self.endIndex and newElements.isEmpty, O(N) otherwise. Declaration mutating func replaceRange<C : CollectionType where C.Generator.Element == Character>(subRange: Range<String.CharacterView.Index>, with newElements: C) mutating func reserveCapacity(_:) Reserve enough space to store n ASCII characters. Complexity: O(n). Declaration mutating func reserveCapacity(n: Int) Declared In String.CharacterView, RangeReplaceableCollectionType func reverse() Returns an Array containing the elements of self in reverse order. Complexity: O(N), where N is the length of self. Declaration func reverse() -> [Character] Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func sort() Returns an Array containing the sorted elements of source. The sorting algorithm is not stable (can change the relative order of elements that compare equal). Requires: The less-than operator (func <) defined in the Comparable conformance is a strict weak ordering over the elements in self. Declaration func sort() -> [Character] Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func sort(_:) Returns an Array containing the sorted elements of source according to isOrderedBefore. The sorting algorithm is not stable (can change the relative order of elements for which isOrderedBefore does not establish an order). Requires: isOrderedBefore is a strict weak ordering over the elements in self. Declaration func sort(@noescape isOrderedBefore: (Character, Character) -> Bool) -> [Character] Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func split(_:allowEmptySlices:isSeparator:) Returns the maximal SubSequences of self, in order, that don't contain elements satisfying the predicate isSeparator. maxSplit: The maximum number of SubSequences to return, minus 1. If maxSplit + 1 SubSequences are returned, the last one is a suffix of self containing the remaining elements. The default value is Int.max. allowEmptySubsequences: If true, an empty SubSequence is produced in the result for each pair of consecutive elements satisfying isSeparator. The default value is false. Requires: maxSplit >= 0 Declaration func split(maxSplit: Int = default, allowEmptySlices: Bool = default, @noescape isSeparator: (Character) throws -> Bool) rethrows -> [String.CharacterView] Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func split(_:maxSplit:allowEmptySlices:) Returns the maximal SubSequences of self, in order, around a separator element. maxSplit: The maximum number of SubSequences to return, minus 1. If maxSplit + 1 SubSequences are returned, the last one is a suffix of self containing the remaining elements. The default value is Int.max. allowEmptySubsequences: If true, an empty SubSequence is produced in the result for each pair of consecutive elements satisfying isSeparator. The default value is false. Requires: maxSplit >= 0 Declaration func split(separator: Character, maxSplit: Int = default, allowEmptySlices: Bool = default) -> [String.CharacterView] Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func startsWith(_:) Returns true iff the initial elements of self are equal to prefix. Returns true if other is empty. Declaration func startsWith<OtherSequence : SequenceType where OtherSequence.Generator.Element == Generator.Element>(other: OtherSequence) -> Bool Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func startsWith(_:isEquivalent:) Returns true iff self begins with elements equivalent to those of other, using isEquivalent as the equivalence test. Returns true if other is empty. Requires: isEquivalent is an equivalence relation. Declaration func startsWith<OtherSequence : SequenceType where OtherSequence.Generator.Element == Generator.Element>(other: OtherSequence, @noescape isEquivalent: (Character, Character) throws -> Bool) rethrows -> Bool Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func suffix(_:) Returns a slice, up to maxLength in length, containing the final elements of s. If maxLength exceeds s.count, the result contains all the elements of s. Requires: maxLength >= 0 Complexity: O(self.count) Declaration func suffix(maxLength: Int) -> String.CharacterView Declared In RangeReplaceableCollectionType, CollectionType, SequenceType func suffixFrom(_:) Returns self[start..<endIndex] Complexity: O(1) Declaration func suffixFrom(start: String.CharacterView.Index) -> String.CharacterView Declared In RangeReplaceableCollectionType, CollectionType func underestimateCount() Returns a value less than or equal to the number of elements in self, nondestructively. Complexity: O(N). Declaration func underestimateCount() -> Int Declared In RangeReplaceableCollectionType, CollectionType, SequenceType