Initializer

init(exactly:)

Creates a new instance initialized to the given value, if it can be represented without rounding.

Declaration

init?(exactly other: Double)

Parameters

other

The value to use for the new instance.

Discussion

If other can’t be represented as an instance of Double without rounding, the result of this initializer is nil. In particular, passing NaN as other always results in nil.

let x: Double = 21.25
let y = Double(exactly: x)
// y == Optional.some(21.25)

let z = Double(exactly: Double.nan)
// z == nil

See Also

Converting with No Loss of Precision

init?<Source>(exactly: Source)

Creates a new instance from the given value, if it can be represented exactly.

init?<Source>(exactly: Source)

Creates a new value, if the given integer can be represented exactly.

init?(exactly: Float)

Creates a new instance initialized to the given value, if it can be represented without rounding.

init?(exactly: Float80)

Creates a new instance initialized to the given value, if it can be represented without rounding.

init?(exactly: NSNumber)