CODEWITHSUNDEEP
swiftgenericstype-conversion
Damian Dudycz
Damian Dudycz

Reputation: 2800

FloatingPoint extension - init with other FloatingPoint type

I need to write an initializer for any FloatingPoint value, which can take other type of FloatingPoint, and convert it to Self. Is this possible in swift? I tried something like this:

init<FloatingPointType: FloatingPoint>(_ value: FloatingPointType) {
    guard let sameValue = value as? Self else {
        // Pass throu double to get best precision
        self.init(Double(value))
        return
    }
    self = sameValue // The same type
}

But this just creates infinite loop. The problem is with creating new self, there is no initializer that takes any other FloatingPoint. I think this might be impossible, but maybe there is some way to achieve this.

Upvotes: 0

Views: 128

Answers (1)

ielyamani
ielyamani

Reputation: 18591

Such initializers already exist in the standard library:

let a: Double = Double(3.625)

//From Double to Float and Float80
let b: Float = Float(a)
let c: Float80 = Float80(a)

//From Float to Double and Float80
let d: Double = Double(b)
let e: Float80 = Float80(b)

//From Float80 to Double and Float
let f: Double = Double(c)
let g: Float = Float(c)

You can find it right here:

public init<Source : BinaryFloatingPoint>(_ value: Source) {
    self = Self._convert(from: value).value
}

Upvotes: 1

Related Questions