async/await

The concept of async/await in Swift is a key feature for handling asynchronous operations. In Swift, when a function may suspend its execution to wait for an asynchronous operation to complete, it is marked with the async keyword. When calling such a function, the await keyword is used to indicate that a suspension can occur at that point in the code. This allows the CPU to be yielded to other tasks that have work to do while waiting for the asynchronous operation to complete.

For example, in the session titled "A Swift Tour: Explore Swift’s features and design," it is explained how Swift uses the async/await syntax to model task suspension in code. This is particularly useful in server development environments where tasks like reading from disk or messaging another service are common. The session also discusses how actors in Swift can be used to encapsulate shared mutable state and ensure that only a single task executes at a time, with calls to actor methods being asynchronous.

Additionally, the session "Explore Swift performance" delves into the implementation details of async functions, explaining how they manage memory allocation and are split into multiple functions at runtime to handle potential suspension points efficiently.

For more detailed information, you can refer to the following sessions:

• A Swift Tour: Explore Swift’s features and design (18:33)
• Explore Swift performance (24:33)

These sessions provide a comprehensive overview of how async/await is utilized in Swift to enhance concurrency and performance.