InitializerSwiftFoundationSwift
init(exactly:)
Creates a new instance from the given integer, if it can be represented exactly.
Available because
Self
conforms toSignedInteger
.Available when
Self
conforms toFixedWidthInteger
init?<T>(exactly source: T) where T : BinaryInteger
Parameters
- source
A value to convert to this type of integer.
Overview
If the value passed as source
is not representable exactly, the result is nil
. In the following example, the constant x
is successfully created from a value of 100
, while the attempt to initialize the constant y
from 1_000
fails because the Int8
type can represent 127
at maximum:
let x = Int8(exactly: 100)
// x == Optional(100)
let y = Int8(exactly: 1_000)
// y == nil