title: Overload function with parameters of same type but different ranges
body: <p>Is it possible to overload a function with the same parameter types but different ranges? I’m trying to implement a subscript extension for <code>Array</code> for negative indices, so that if <code>let a = [3, 1, 4]</code>, <code>a[-1] == 4</code>, <code>a[-2] == 1</code>, etc. Swift’s <code>Array</code> already has a subscript function, so I don’t want to replace it, but create an overloaded function just for negative integers. Is this any way of doing this? Thanks.</p>