advanced(by:)

Declaration

func advanced(by amount: Float16) -> Float16

Return Value

A value that is offset from this value by n.

Discussion

Use the advanced(by:) method in generic code to offset a value by a specified distance. If you’re working directly with numeric values, use the addition operator (+) instead of this method.

func addOne<T: Strideable>(to x: T) -> T
    where T.Stride: ExpressibleByIntegerLiteral
{
    return x.advanced(by: 1)
}

let x = addOne(to: 5)
// x == 6
let y = addOne(to: 3.5)
// y = 4.5

If this type’s Stride type conforms to BinaryInteger, then for a value x, a distance n, and a value y = x.advanced(by: n), x.distance(to: y) == n. Using this method with types that have a noninteger Stride may result in an approximation. If the result of advancing by n is not representable as a value of this type, then a runtime error may occur.