GO FURTHER, FASTER: Try the Swift Career Accelerator today! >>

How to use one-sided ranges

Swift version: 5.10

Paul Hudson    @twostraws   

One-sided ranges allow us to skip either the start or end of a range to have Swift infer the starting point for us. As an example, consider this array:

let characters = ["Dr Horrible", "Captain Hammer", "Penny", "Bad Horse", "Moist"]

If we wanted to read only the first three items from that array, we could use characters[..<3] – we skipped the start point, so Swift will automatically infer the start of the array:

let bigParts = characters[..<3]

That will create an array containing ["Dr Horrible", "Captain Hammer", "Penny"].

Similarly, we could skip the end of the range to have Swift infer the end of the array, like this:

let smallParts = characters[3...]

That will create an array containing ["Bad Horse", "Moist"].

Hacking with Swift is sponsored by Alex.

SPONSORED Alex is the iOS & Mac developer’s ultimate AI assistant. It integrates with Xcode, offering a best-in-class Swift coding agent. Generate modern SwiftUI from images. Fast-apply suggestions from Claude 3.5 Sonnet, o3-mini, and DeepSeek R1. Autofix Swift 6 errors and warnings. And so much more. Start your 7-day free trial today!

Try for free!

Sponsor Hacking with Swift and reach the world's largest Swift community!

Available from iOS 8.0

Similar solutions…

About the Swift Knowledge Base

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

BUY OUR BOOKS
Buy Pro Swift Buy Pro SwiftUI Buy Swift Design Patterns Buy Testing Swift Buy Hacking with iOS Buy Swift Interview Challenges Buy Swift on Sundays Volume One Buy Server-Side Swift Buy Hacking with watchOS Buy Hacking with tvOS Buy Hacking with macOS Buy Dive Into SpriteKit Buy Swift in Sixty Seconds Buy Objective-C for Swift Developers Buy Beyond Code

Was this page useful? Let us know!

Average rating: 5.0/5

 
Unknown user

You are not logged in

Log in or create account
 

Link copied to your pasteboard.