m, _ := time.ParseDuration("1m30s")
	fmt.Printf("Take off in t-%.0f seconds.", m.Seconds())
	// Output: Take off in t-90 seconds.
}

var c chan int

func handle(int) {}

func ExampleAfter() {
	select {
	case m := <-c:
		handle(m)
	case <-time.After(10 * time.Second):
		fmt.Println("timed out")
	}
}

func ExampleSleep() {
	time.Sleep(100 * time.Millisecond)
}