Collections: Shuffling Arrays

This tutorial belongs to the Swift series

Suppose you have an array in Swift, like this:

var items = 1...3

and you want to shuffle it, so that you get its items in random order.

There are 2 ways to do that in Swift.

One way is mutating the original array, and it’s using the shuffle() method that shuffles the items in the array:

items.shuffle()

Note that I used var because an array is a struct, and if I declare it as let then it’s immutable, and you will get an error.

Another way is not mutating the original array, but it’s returning a new array, and it’s using the shuffled() method:

let items = 1...3
let shuffledItems = items.shuffled()

Note that here I am safe to use let to declare my variables because shuffled() does not mutate the original array.