How to use map() with an optional value
Swift version: 5.4
The map() method of optionals allows you to transform the optional if it has a value, or do nothing if it is empty. This makes for shorter and more expressive code than doing a regular unwrap, and doesn’t require you to change your data type.
For example, if you had an optional string like this one:
let name: String? = "twostraws"You could use the map() method to transform it safely, without having to check and unwrap it – if it were nil, the map() call would do nothing.
For example:
let twitterName = name.map { "@\($0)" }
print(twitterName)That will print @twostraws.
SPONSORED Join a FREE crash course for iOS devs who want to become complete senior developers — from October 18th to 24th. Learn how to apply iOS app architecture patterns through a series of lectures and practical coding sessions.
Sponsor Hacking with Swift and reach the world's largest Swift community!
Available from iOS – learn more in my book Pro Swift
Similar solutions…
- Optional vs implicitly unwrapped optional: what’s the difference?
- How to create a random terrain tile map using SKTileMapNode and GKPerlinNoiseSource
- How to use flatMap() with an optional value
- What is an optional value in Swift?
- How to show a Map view
About the Swift Knowledge Base
This is part of the Swift Knowledge Base, a free, searchable collection of solutions for common iOS questions.
