Swift Concurrency

Apple introduced Swift concurrency, which adds support for structured asynchronous and parallel programming to Swift 5.5, during WWDC21. It allows you to write concurrent code, which is more readable and easier to understand. During WWDC24, Apple introduced Swift 6, which makes concurrency programming easier by diagnosing data races at compile time.

At the present time, it is not recommended to turn strict concurrency on for large existing projects, as it is likely to generate multiple errors and warnings. However, as this is Apple’s direction going forward, you will be turning it on for the project in this chapter and in Part 3 of this book so you may learn and gain experience with it.

In this chapter, you will learn the basic concepts of Swift concurrency. Next, you will examine an app without concurrency and explore its issues. After that, you will use async/await to implement concurrency in the app. Finally, you’ll make your...