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Creates an instance equivalent to the given range.

An equivalent range must be representable as an instance of Range. For example, passing a closed range with an upper bound of Int.max triggers a runtime error, because the resulting half-open range would require an upper bound of Int.max + 1, which is not representable as an Int.

other: A range to convert to a Range instance.

Declaration

init(_ other: ClosedRange<Bound>)

Creates an instance equivalent to the given range.

An equivalent range must be representable as an instance of Range. For example, passing a closed range with an upper bound of Int.max triggers a runtime error, because the resulting half-open range would require an upper bound of Int.max + 1, which is not representable as an Int.

other: A range to convert to a Range instance.

Declaration

init(_ other: CountableClosedRange<Bound>)

Creates an instance equivalent to the given range.

other: A range to convert to a Range instance.

Declaration

init(_ other: CountableRange<Bound>)

Creates an instance equivalent to the given range.

other: A range to convert to a Range instance.

Declaration

init(_ other: Range<Bound>)

Creates an instance with the given bounds.

Because this initializer does not perform any checks, it should be used as an optimization only when you are absolutely certain that lower is less than or equal to upper. Using the half-open range operator (..<) to form Range instances is preferred.

bounds: A tuple of the lower and upper bounds of the range.

Declaration

init(uncheckedBounds bounds: (lower: Bound, upper: Bound))

The number of values contained in the range.

Declaration

var count: Bound.Stride { get }

The custom mirror for this instance.

If this type has value semantics, the mirror should be unaffected by subsequent mutations of the instance.

Declaration

var customMirror: Mirror { get }

A textual representation of the range, suitable for debugging.

Declaration

var debugDescription: String { get }

A textual representation of the range.

Declaration

var description: String { get }

A Boolean value indicating whether the range contains no elements.

An empty Range instance has equal lower and upper bounds.

let empty: Range = 10..<10
print(empty.isEmpty)
// Prints "true"

Declaration

var isEmpty: Bool { get }

The range's lower bound.

In an empty range, lowerBound is equal to upperBound.

Declaration

var lowerBound: Bound { get }

The range's upper bound.

In an empty range, upperBound is equal to lowerBound. A Range instance does not contain its upper bound.

Declaration

var upperBound: Bound { get }

Returns a Boolean value indicating whether two ranges are equal.

Two ranges are equal when they have the same lower and upper bounds. That requirement holds even for empty ranges.

let x: Range = 5..<15
print(x == 5..<15)
// Prints "true"

let y: Range = 5..<5
print(y == 15..<15)
// Prints "false"

Parameters: lhs: A range to compare. rhs: Another range to compare.

Declaration

func ==(lhs: Range<Bound>, rhs: Range<Bound>) -> Bool

Returns a Boolean value indicating whether a value is included in a range.

You can use this pattern matching operator (~=) to test whether a value is included in a range. The following example uses the ~= operator to test whether an integer is included in a range of single-digit numbers.

let chosenNumber = 3
if 0..<10 ~= chosenNumber {
    print("\(chosenNumber) is a single digit.")
}
// Prints "3 is a single digit."

The ~= operator is used internally in case statements for pattern matching. When you match against a range in a case statement, this operator is called behind the scenes.

switch chosenNumber {
case 0..<10:
    print("\(chosenNumber) is a single digit.")
case Int.min..<0:
    print("\(chosenNumber) is negative.")
default:
    print("\(chosenNumber) is positive.")
}
// Prints "3 is a single digit."

Parameters: lhs: A range. rhs: A value to match against lhs.

Declaration

func ~=(pattern: Range<Bound>, value: Bound) -> Bool

Returns a copy of this range clamped to the given limiting range.

The bounds of the result are always limited to the bounds of limits. For example:

let x: Range = 0..<20
print(x.clamped(to: 10..<1000))
// Prints "10..<20"

If the two ranges do not overlap, the result is an empty range within the bounds of limits.

let y: Range = 0..<5
print(y.clamped(to: 10..<1000))
// Prints "10..<10"

limits: The range to clamp the bounds of this range. Returns: A new range clamped to the bounds of limits.

Declaration

func clamped(to limits: Range<Bound>) -> Range<Bound>

Returns a Boolean value indicating whether the given element is contained within the range.

Because Range represents a half-open range, a Range instance does not contain its upper bound. element is contained in the range if it is greater than or equal to the lower bound and less than the upper bound.

element: The element to check for containment. Returns: true if element is contained in the range; otherwise, false.

Declaration

func contains(_ element: Bound) -> Bool

Returns a Boolean value indicating whether this range and the given range contain an element in common.

This example shows two overlapping ranges:

let x: Range = 0..<20
print(x.overlaps(10...1000 as ClosedRange))
// Prints "true"

Because a half-open range does not include its upper bound, the ranges in the following example do not overlap:

let y: ClosedRange = 20..<30
print(x.overlaps(y))
// Prints "false"

other: A range to check for elements in common. Returns: true if this range and other have at least one element in common; otherwise, false.

Declaration

func overlaps(_ other: ClosedRange<Bound>) -> Bool

Returns a Boolean value indicating whether this range and the given range contain an element in common.

This example shows two overlapping ranges:

let x: Range = 0..<20
print(x.overlaps(10...1000 as CountableClosedRange))
// Prints "true"

Because a half-open range does not include its upper bound, the ranges in the following example do not overlap:

let y: CountableClosedRange = 20..<30
print(x.overlaps(y))
// Prints "false"

other: A range to check for elements in common. Returns: true if this range and other have at least one element in common; otherwise, false.

Declaration

func overlaps(_ other: CountableClosedRange<Bound>) -> Bool

Returns a Boolean value indicating whether this range and the given range contain an element in common.

This example shows two overlapping ranges:

let x: Range = 0..<20
print(x.overlaps(10..<1000 as CountableRange))
// Prints "true"

Because a half-open range does not include its upper bound, the ranges in the following example do not overlap:

let y: CountableRange = 20..<30
print(x.overlaps(y))
// Prints "false"

other: A range to check for elements in common. Returns: true if this range and other have at least one element in common; otherwise, false.

Declaration

func overlaps(_ other: CountableRange<Bound>) -> Bool

Returns a Boolean value indicating whether this range and the given range contain an element in common.

This example shows two overlapping ranges:

let x: Range = 0..<20
print(x.overlaps(10..<1000 as Range))
// Prints "true"

Because a half-open range does not include its upper bound, the ranges in the following example do not overlap:

let y: Range = 20..<30
print(x.overlaps(y))
// Prints "false"

other: A range to check for elements in common. Returns: true if this range and other have at least one element in common; otherwise, false.

Declaration

func overlaps(_ other: Range<Bound>) -> Bool