Redeclaring members in an extension hides the original member *sometimes*. Why?

Question

By chance, I discovered that you can do this without the compiler complaining:

extension Date {
    var timeIntervalSinceNow: TimeInterval {
        return 1         


        

Answer 1

This works because you are declaring this extension in a separate module from the original variable declaration.

Across modules a variable name can be overloaded but in my mind this has been a shortcoming of Swift as there is currently no way to explicitly state which module declaration it is that you want.