Want to work on your asynchronous code in a Swift Playground? Just set needsIndefiniteExecution to true to keep it running:

import PlaygroundSupport

PlaygroundPage.current.needsIndefiniteExecution = true

DispatchQueue.main.asyncAfter(deadline: .now() + 3) {
    let greeting = "Hello after 3 seconds"
    print(greeting)
}

To stop the playground from executing, simply call PlaygroundPage.current.finishExecution().

Support Swift by Sundell by checking out this sponsor:

Essential Developer: Learn the most up-to-date techniques and strategies for testing new and legacy Swift code in this free practical course for developers who want to become complete senior iOS developers. This virtual event includes lectures, mentoring sessions, and step-by-step instructions. Click to learn more.