Is Swift Pass By Value or Pass By Reference

Question

I\'m really new to Swift and I just read that classes are passed by reference and arrays/strings etc. are copied.

Is the pass by reference the same way as in Objecti

Answer 1

When you use inout with an infix operator such as += then the &address symbol can be ignored. I guess the compiler assumes pass by reference?

extension Dictionary {
    static func += (left: inout Dictionary, right: Dictionary) {
        for (key, value) in right {
            left[key] = value
        }
    }
}

origDictionary += newDictionaryToAdd

And nicely this dictionary 'add' only does one write to the original reference too, so great for locking!