Converting a Duration to a Double of seconds?

perhaps i am going crazy, but is there really no standard library API to convert a Duration to a Double of (milli)seconds?

next best thing i could think of is dividing by milliseconds(1). but this seems less efficient than doing the arithmetic manually.

let milliseconds:Double = duration / .milliseconds(1)

You’d compute it from components:

let seconds = Double(duration.components.seconds)

this loses the fractional component though?

Ah, your question was ambiguous on that point; you'd add the attoseconds component back (appropriately scaled) for the fractional component, of course.

Will this work?

extension Duration {
var inMilliseconds: Double {
Double((self * 1000).components.seconds)

Edit: no, that was not correct, this one is better:

extension Duration {
    var inMilliseconds: Double {
        let v = components
        return Double(v.seconds) * 1000 + Double(v.attoseconds) * 1e-15

Gee, I've just corrected another mistake (was multiplying integer seconds - which may overflow) :sweat_smile: Shouldn't this be in the standard library or was it deliberately not included?

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