How do I use Swift actors?

To use Swift actors, you can follow these steps:

Define an Actor: Actors in Swift are similar to classes but are designed to handle concurrency by serializing access to their state. You can define an actor using the actor keyword.

actor UserStore {
    var users: [String] = []
    
    func addUser(_ user: String) {
        users.append(user)
    }
    
    func getUsers() -> [String] {
        return users
    }
}

Accessing Actor Methods: When you call methods on an actor from outside its context, these calls are asynchronous. You need to use the await keyword.
```
let userStore = UserStore()

Task {
    await userStore.addUser("Alice")
    let users = await userStore.getUsers()
    print(users)
}
```

Concurrency Safety: Actors automatically protect their state by ensuring that only one task can access their state at a time. This helps prevent data races.

actor UserStore {
    var users: [String] = []
    
    func addUser(_ user: String) {
        users.append(user)
    }
    
    func getUsers() -> [String] {
        return users
    }
}

let userStore = UserStore()

Task {
    await userStore.addUser("Alice")
    let users = await userStore.getUsers()
    print(users)
}

Using Actors in HTTP Handlers: When using actors in an HTTP request handler, you need to ensure that accesses to the actor are asynchronous.
```
func handleRequest(username: String) async -> [String] {
    await userStore.addUser(username)
    return await userStore.getUsers()
}
```

For more detailed information, you can refer to the session A Swift Tour: Explore Swift’s features and design which covers the basics of writing concurrent code in Swift, including tasks, async/await, and actors.

How do I use Swift actors?

Relevant Sessions