UPGRADE YOUR SKILLS: Learn advanced Swift and SwiftUI on Hacking with Swift+! >>

How to unwrap an optional in Swift

Swift version: 5.6

Paul Hudson    @twostraws   

Optional values are a central concept in Swift, although admittedly they can be a little hard to understand at first. Put simply, an optional value is one that may or may not exist, which means Swift won't let you use it by accident – you need to either check whether it has a value and unwrap it, or force unwrap. Of the two options the first is definitely preferable, because it's significantly safer.

To check whether an optional has a value then unwrap it all in one, you should use if let syntax, like this:

// fetch an example optional string
let optionalString = fetchOptionalString()

// now unwrap it
if let unwrapped = optionalString {
    print(unwrapped)
}

In that example, the print(unwrapped) line will only be executed if optionalString has a value. If that line is reached, you can know for sure that unwrapped has a value that you can use, which makes that code safe.

Hacking with Swift is sponsored by RevenueCat

SPONSORED Take the pain out of configuring and testing your paywalls. RevenueCat's Paywalls allow you to remotely configure your entire paywall view without any code changes or app updates.

Learn more here

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

Available from iOS 7.0 – see Hacking with Swift tutorial 1

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 Coding Challenges Buy Swift on Sundays Volume One Buy Server-Side Swift Buy Advanced iOS Volume One Buy Advanced iOS Volume Two Buy Advanced iOS Volume Three 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: 4.1/5

 
Unknown user

You are not logged in

Log in or create account
 

Link copied to your pasteboard.