How to loop through an array in reverse

Swift version: 5.6

Paul Hudson @twostraws May 28th 2019

If you want to read through an array in reverse, you should use the reversed() method. You can use this as part of the regular fast enumeration technique if you want, which would give you code like this:

let array = ["Apples", "Peaches", "Plums"]

for item in array.reversed() {
    print("Found \(item)")
}

You can also reverse an enumerated array just by appending the method call, like this:

for (index, item) in array.reversed().enumerated() {
    print("Found \(item) at position \(index)")
}

Note that whether you call reversed() then enumerated() or vice versa matters! In the above code, enumerate will count upwards, but if you use array.enumerated().reversed() it will count backwards.