Range
A half-open interval from a lower bound up to, but not including, an upper bound.
@frozen struct Range<Bound> where Bound : ComparableYou create a Range instance by using the half-open range operator (..<).
let underFive = 0.0..<5.0You can use a Range instance to quickly check if a value is contained in a particular range of values. For example:
underFive.contains(3.14)
// true
underFive.contains(6.28)
// false
underFive.contains(5.0)
// falseRange instances can represent an empty interval, unlike ClosedRange.
let empty = 0.0..<0.0
empty.contains(0.0)
// false
empty.isEmpty
// trueUsing a Range as a Collection of Consecutive Values
When a range uses integers as its lower and upper bounds, or any other type that conforms to the Strideable protocol with an integer stride, you can use that range in a for-in loop or with any sequence or collection method. The elements of the range are the consecutive values from its lower bound up to, but not including, its upper bound.
for n in 3..<5 {
print(n)
}
// Prints "3"
// Prints "4"Because floating-point types such as Float and Double are their own Stride types, they cannot be used as the bounds of a countable range. If you need to iterate over consecutive floating-point values, see the stride(from:to:by:) function.
Citizens in Swift
Members
init(uncheckedBounds: (lower: Bound, upper: Bound)) Creates an instance with the given bounds.
var isEmpty: BoolA Boolean value indicating whether the range contains no elements.
let lowerBound: BoundThe range’s lower bound.
let upperBound: BoundThe range’s upper bound.
func contains(Bound) -> Bool Returns a Boolean value indicating whether the given element is contained within the range.
Citizens in Swift
where Bound:Strideable, Bound.Stride:SignedIntegerConformances
protocol BidirectionalCollectionA collection that supports backward as well as forward traversal.
protocol CollectionA sequence whose elements can be traversed multiple times, nondestructively, and accessed by an indexed subscript.
protocol RandomAccessCollectionA collection that supports efficient random-access index traversal.
protocol SequenceA type that provides sequential, iterated access to its elements.
Members
init(ClosedRange<Bound>) Creates an instance equivalent to the given
ClosedRange.var endIndex: Range<Bound>.Indexvar indices: Range<Bound>.IndicesThe indices that are valid for subscripting the range, in ascending order.
var startIndex: Range<Bound>.Indexsubscript(Range<Range<Bound>.Index>) -> Range<Bound> Accesses the subsequence bounded by the given range.
subscript(Range<Bound>.Index) -> Range<Bound>.Element Accesses the element at specified position.
func distance(from: Range<Bound>.Index, to: Range<Bound>.Index) -> Int func index(Range<Bound>.Index, offsetBy: Int) -> Range<Bound>.Index func index(after: Range<Bound>.Index) -> Range<Bound>.Index func index(before: Range<Bound>.Index) -> Range<Bound>.Index typealias Elementtypealias IndexA type that represents a position in the range.
typealias Indicestypealias Iteratortypealias SubSequenceinit(Range<Bound>) Now that Range is conditionally a collection when Bound: Strideable, CountableRange is no longer needed. This is a deprecated initializer for any remaining uses of Range(countableRange).
Citizens in Swift
where Bound:ComparableConformances
protocol CustomDebugStringConvertibleA type with a customized textual representation suitable for debugging purposes.
protocol CustomReflectableA type that explicitly supplies its own mirror.
protocol CustomStringConvertibleA type with a customized textual representation.
protocol EquatableA type that can be compared for value equality.
protocol RangeExpressionA type that can be used to slice a collection.
Members
var customMirror: Mirrorvar debugDescription: StringA textual representation of the range, suitable for debugging.
var description: StringA textual representation of the range.
static func == (Range<Bound>, Range<Bound>) -> Bool Returns a Boolean value indicating whether two ranges are equal.
func clamped(to: Range<Bound>) -> Range<Bound> Returns a copy of this range clamped to the given limiting range.
func overlaps(ClosedRange<Bound>) -> Bool func overlaps(Range<Bound>) -> Bool Returns a Boolean value indicating whether this range and the given range contain an element in common.
func relative<C>(to: C) -> Range<Bound> Returns the range of indices described by this range expression within the given collection.
Features
static func != (Self, Self) -> Bool static func ~= (Self, Self.Bound) -> Bool Returns a Boolean value indicating whether a value is included in a range.
Citizens in Swift
where Bound:Comparable, Bound:DecodableConformances
protocol DecodableA type that can decode itself from an external representation.
Members
Citizens in Swift
where Bound:Comparable, Bound:EncodableConformances
protocol EncodableA type that can encode itself to an external representation.
Members
Citizens in Swift
where Bound:Comparable, Bound:SendableConformances
protocol SendableA type whose values can safely be passed across concurrency domains by copying.
Citizens in Swift
where Bound:Comparable, Bound:HashableConformances
protocol HashableA type that can be hashed into a
Hasherto produce an integer hash value.
Members
func hash(into: inout Hasher) Hashes the essential components of this value by feeding them into the given hasher.
Available in _RegexParser
where Bound:ComparableMembers
Available in Foundation
where Bound:BinaryIntegerMembers
Available in Foundation
where Bound == AttributedString.IndexMembers
Available in Foundation
where Bound == String.IndexMembers
Available in Foundation
where Bound == IntMembers
Extension in Markdown
where Bound == SourceLocationMembers
func diagnosticDescription(includePath: Bool) -> String A textual description for use in diagnostics.
init(start: Bound, end: Bound) var end: SourceLocationvar start: SourceLocation