Modern Concurrency: Beyond the Basics

Oct 20 2022 · Swift 5.5, iOS 15, Xcode 13.4

Part 1: AsyncStream & Continuations

05. Using a Buffered AsyncStream

Episode complete

Play next episode

About this episode

Leave a rating/review

See forum comments
Cinema mode Mark complete Download course materials
Previous episode: 04. Using AsyncStream for Notifications Next episode: 06. Unit Testing

Get immediate access to this and 4,000+ other videos and books.

Take your career further with a Kodeco Personal Plan. With unlimited access to over 40+ books and 4,000+ professional videos in a single subscription, it's simply the best investment you can make in your development career.

Learn more Already a subscriber? Sign in.

Notes: 05. Using a Buffered AsyncStream

Use Xcode 13 for this exercise. Xcode 14 beta uses Swift 6, which doesn’t allow using countdown in the scheduledTRimer closure.

Heads up... You've reached locked video content where the transcript will be shown as obfuscated text.

Your challenge is to rewrite countdown(to:) using the buffered push-based version of AsyncStream.

let counter = AsyncStream<String> { continuation in
  var countdown = 3
    withTimeInterval: 1.0,
    repeats: true
  ) { timer in

continuation.yield("\(countdown) ...")
countdown -= 1
) { timer in
  🟩guard countdown > 0 else {
    continuation.yield("🎉 " + message)
  🟥continuation.yield("\(countdown) ...")
  countdown -= 1
continuation.yield(with: .success("🎉 " + message))