Swift.Extensions var and func. Which one is better?

Question

I'm a newbie. Here is the code

extension Double  {
    func abs1() -> Double  {
        return ( self > 0 ) ? self : -1.0 * self
    }

    var abs2 : Double {
        return ( self > 0 ) ? self : -1.0 * self
    }
}

I would like to know what is the difference between the abs1 () function and the abs2 variable, how they work and which one is better?

Answer 1

They are the same in how they work. This is really a signal of intent. Personally, I would recommend a function in this case, which is a little contrary to intuition, so I will explain.

First rule: "are there any side effects?" If so, it should be a function.

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