NEW: Master Swift design patterns with my latest book! >>

Using stride() to loop over a range of numbers

Written by Paul Hudson    @twostraws

Swift has a helpful stride(), which lets you move from one value to another using any increment – and even lets you specify whether the upper bound is exclusive or inclusive.

First, some examples. This first example counts from 0 to 10 in 2s:

for i in stride(from: 0, to: 10, by: 2) {
    print(i)
}

This second example counts from 0.1 up to to 0.5, exclusive:

for i in stride(from: 0, to: 0.5, by: 0.1) {
    print(i)
}

Both those examples use stride(from:to:by:), which counts from the start point up to by excluding the to parameter. If you want to count up and including the to parameter, you should use stride(from:through:by:), like this:

for i in stride(from: 0, through: 10, by: 2) {
    print(i)
}

Available from iOS 7.0

Did this solution work for you? Please pass it on!

Other people are reading…

About the Swift Knowledge Base

This is part of the Swift Knowledge Base, a free, searchable collection of solutions for common iOS questions.

Need to know Objective-C fast?

I wrote a book dedicated to teaching Objective-C to developers who already know Swift – it's the fastest way to get up to speed!

Click here to visit the Hacking with Swift store >>