String.UnicodeScalarView

struct String.UnicodeScalarView

A collection of Unicode scalar values that encodes a String value.

Inheritance CollectionType, CustomDebugStringConvertible, CustomStringConvertible, Indexable, RangeReplaceableCollectionType, SequenceType, _Reflectable View Protocol Hierarchy →
Associated Types
Generator = String.UnicodeScalarView.Generator

Type alias inferred.

Element = UnicodeScalar

Type alias inferred.

Index = String.UnicodeScalarView.Index

Type alias inferred.

SubSequence = String.UnicodeScalarView

Type alias inferred.

Nested Types String.UnicodeScalarView.Index, String.UnicodeScalarView.Generator
Import import Swift

Initializers

init()

Construct an empty instance.

Declaration

init()
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.UnicodeScalarView.Index.Distance

Returns the number of elements.

Complexity: O(1) if Index conforms to RandomAccessIndexType; O(N) otherwise.

Declaration

var count: String.UnicodeScalarView.Index.Distance { get }

Declared In

RangeReplaceableCollectionType , CollectionType
var debugDescription: String

Declaration

var debugDescription: String { get }
var description: String

Declaration

var description: String { get }
var endIndex: String.UnicodeScalarView.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.UnicodeScalarView.Index { get }
var first: UnicodeScalar?

Returns the first element of self, or nil if self is empty.

Complexity: O(1)

Declaration

var first: UnicodeScalar? { get }

Declared In

RangeReplaceableCollectionType , CollectionType
var indices: Range<String.UnicodeScalarView.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.UnicodeScalarView.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: UnicodeScalar?

Declaration

var last: UnicodeScalar? { get }

Declared In

RangeReplaceableCollectionType , CollectionType
var lazy: LazyCollection<String.UnicodeScalarView>

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.UnicodeScalarView> { get }

Declared In

RangeReplaceableCollectionType , CollectionType
var startIndex: String.UnicodeScalarView.Index

The position of the first UnicodeScalar if the String is non-empty; identical to endIndex otherwise.

Declaration

var startIndex: String.UnicodeScalarView.Index { get }

Subscripts

subscript(_: Range<String.UnicodeScalarView.Index>)

Access the elements delimited by the given half-open range of indices.

Complexity: O(1) unless bridging from Objective-C requires an O(N) conversion.

Declaration

subscript(r: Range<String.UnicodeScalarView.Index>) -> String.UnicodeScalarView { get }
subscript(_: String.UnicodeScalarView.Index)

Access the element at position.

Requires: position is a valid position in self and position != endIndex.

Declaration

subscript(position: String.UnicodeScalarView.Index) -> UnicodeScalar { get }

Instance Methods

mutating func append(_:)

Append x to self.

Complexity: Amortized O(1).

Declaration

mutating func append(x: UnicodeScalar)

Declared In

String.UnicodeScalarView, RangeReplaceableCollectionType
mutating func appendContentsOf(_:)

Append the elements of newElements to self.

Complexity: O(length of result).

Declaration

mutating func appendContentsOf<S : SequenceType where S.Generator.Element == UnicodeScalar>(newElements: S)

Declared In

String.UnicodeScalarView, RangeReplaceableCollectionType
func contains(_:)

Returns true iff an element in self satisfies predicate.

Declaration

func contains(@noescape predicate: (UnicodeScalar) 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.UnicodeScalarView

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.UnicodeScalarView

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.UnicodeScalarView

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.UnicodeScalarView

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: (UnicodeScalar, UnicodeScalar) 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.UnicodeScalarView>

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: (UnicodeScalar) throws -> Bool) rethrows -> [UnicodeScalar]

Declared In

RangeReplaceableCollectionType, CollectionType, SequenceType
func flatMap<T>(_: (UnicodeScalar) 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: (UnicodeScalar) throws -> T?) rethrows -> [T]

Declared In

RangeReplaceableCollectionType, CollectionType, SequenceType
func flatMap<S : SequenceType>(_: (UnicodeScalar) 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: (UnicodeScalar) 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: (UnicodeScalar) throws -> Void) rethrows

Declared In

RangeReplaceableCollectionType, CollectionType, SequenceType
func generate()

Returns a generator over the UnicodeScalars that comprise this sequence.

Complexity: O(1).

Declaration

func generate() -> String.UnicodeScalarView.Generator
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: (UnicodeScalar) throws -> Bool) rethrows -> String.UnicodeScalarView.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: UnicodeScalar, atIndex i: String.UnicodeScalarView.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.UnicodeScalarView.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: (UnicodeScalar, UnicodeScalar) 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: (UnicodeScalar) 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() -> UnicodeScalar?

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: (UnicodeScalar, UnicodeScalar) throws -> Bool) rethrows -> UnicodeScalar?

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() -> UnicodeScalar?

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: (UnicodeScalar, UnicodeScalar) throws -> Bool) rethrows -> UnicodeScalar?

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() -> UnicodeScalar?

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() -> UnicodeScalar?

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.UnicodeScalarView

Declared In

RangeReplaceableCollectionType, CollectionType, SequenceType
func prefixThrough(_:)

Returns prefixUpTo(position.successor())

Complexity: O(1)

Declaration

func prefixThrough(position: String.UnicodeScalarView.Index) -> String.UnicodeScalarView

Declared In

RangeReplaceableCollectionType, CollectionType
func prefixUpTo(_:)

Returns self[startIndex..<end]

Complexity: O(1)

Declaration

func prefixUpTo(end: String.UnicodeScalarView.Index) -> String.UnicodeScalarView

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, UnicodeScalar) 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.UnicodeScalarView.Index) -> UnicodeScalar

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() -> UnicodeScalar

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() -> UnicodeScalar

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.UnicodeScalarView.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 == UnicodeScalar>(subRange: Range<String.UnicodeScalarView.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.UnicodeScalarView, 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() -> [UnicodeScalar]

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() -> [UnicodeScalar]

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: (UnicodeScalar, UnicodeScalar) -> Bool) -> [UnicodeScalar]

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: (UnicodeScalar) throws -> Bool) rethrows -> [String.UnicodeScalarView]

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: UnicodeScalar, maxSplit: Int = default, allowEmptySlices: Bool = default) -> [String.UnicodeScalarView]

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: (UnicodeScalar, UnicodeScalar) 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.UnicodeScalarView

Declared In

RangeReplaceableCollectionType, CollectionType, SequenceType
func suffixFrom(_:)

Returns self[start..<endIndex]

Complexity: O(1)

Declaration

func suffixFrom(start: String.UnicodeScalarView.Index) -> String.UnicodeScalarView

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