For loops

Swift has a few ways of writing loops, but their underlying mechanism is the same: run some code repeatedly until a condition evaluates as false.

The most common loop in Swift is a for loop: it will loop over arrays and ranges, and each time the loop goes around it will pull out one item and assign to a constant.

For example, here’s a range of numbers:

let count = 1...10

We can use a for loop to print each item like this:

for number in count {
    print("Number is \(number)")
}

We can do the same with arrays:

let albums = ["Red", "1989", "Reputation"]

for album in albums {
    print("\(album) is on Apple Music")
}

If you don’t use the constant that for loops give you, you should use an underscore instead so that Swift doesn’t create needless values:

print("Players gonna ")

for _ in 1...5 {
    print("play")
}

Save 50% on all books and bundles

The biggest ever Hacking with Swift sale is now on, letting you save 50% on all books and bundles. Learn something new with Swift and enjoy great savings while the sale lasts!

Click here to save 50% in our Black Friday sale!