A trivial, useless example of async/await using Async that does something and returns something.

AsyncDemo2.swift

let Q1 = DispatchQueue(label: "DemoQueue1")
let Q2 = DispatchQueue(label: "DemoQueue2")

func demo() -> Task<Int> {
	return async { (task: Task<Int>) in
		var calculation = 0
		Q2.async {
			print("Doing some expensive calculation of universal truths...")
			calculation = 42
			print("Figured it all out, lets wake up.")
			Async.Wake(task)
		}
		print("Suspend until some work is done...")
		Async.Suspend()
		return calculation
	}
}

Q1.async {
	print("The magic number is: \(await (demo()))")
}