Overview
In some cases, you would like to pass a variable by reference. In Swift, we use the inout and the & keys.
Here’s an example of a generic swap.
1
2
3
4
5
6
7
8
9
10
11
12
13
var lucky = 7
var unlucky = 13
func swapTwoVariables<T>(inout first: T, inout second: T) {
let temp = first
first = second
second = temp
}
swapTwoVariables(&lucky, &unlucky)
println("lucky: \(lucky) unlucky: \(unlucky)")
// "lucky: 13 unlucky: 7"