Swift 3 How to declare an assignment operator on custom class

Question

I would like to declare an assignment operator on my custom class CGFloat01 so that I can use it like so:

var a:CGFloat01
var b:CGFloat

a = b

I tried the following, but it doesn't compile:

func = (lhs:CGFloat01, rhs:CGFloat) -> CGFloat01 {
    lhs.value = rhs
    return lhs
}

God I hate implicit behaviour like this – Alexander Dec 15 '16 at 16:02 — Alexander, Dec 15 '16 at 16:02

score 2 · Accepted Answer · answered Dec 15 '16 at 14:50

2

You can't

From the Swift Documentation

It is not possible to overload the default assignment operator (=). Only the compound assignment operators can be overloaded. Similarly, the ternary conditional operator (a ? b : c) cannot be overloaded.

answered Dec 15 '16 at 14:50

Mgetz

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well ... that explains it – andrewz Dec 15 '16 at 14:55
@andrewz most languages don't trust you with this power, as far as I know C++ is the only one that does. – Mgetz Dec 15 '16 at 14:57

Swift 3 How to declare an assignment operator on custom class

1 Answers1