String interpolation

You’ve seen how you can type values for strings directly into your code, but Swift also has a feature called string interpolation – the ability to place variables inside your strings to make them more useful.

You can place any type of variable inside your string – all you have to do is write a backslash, \, followed by your variable name in parentheses. For example:

var score = 85
var str = "Your score was \(score)"

As you can see in the playground output, that sets the str variable to be “Your score was 85”.

You can do this as many times as you need, making strings out of strings if you want:

var results = "The test results are here: \(str)"

As you’ll see later on, string interpolation isn’t just limited to placing variables – you can actually run code inside there.