Swift is what’s known as a type-safe language, which means that every variable must be of one specific type. The
str variable that Xcode created for us holds a string of letters that spell “Hello, playground”, so Swift assigns it the type
On the other hand, if we want to store someone’s age we might make a variable like this:
var age = 38
That holds a whole number, so Swift assigns the type
Int – short for “integer”.
If you have large numbers, Swift lets you use underscores as thousands separators – they don’t change the number, but they do make it easier to read. For example:
var population = 8_000_000
Strings and integers are different types, and they can’t be mixed. So, while it’s safe to change
str to “Goodbye”, I can’t make it 38 because that’s an
Int not a
SPONSORED Play is the first native iOS design tool created for designers and engineers. You can install Play for iOS and iPad today and sign up to check out the Beta of our macOS app with SwiftUI code export. We're also hiring engineers!
Link copied to your pasteboard.