good good study, day day up!

vendor/gopl.io/ch8/countdown1/countdown.go

@@ -0,0 +1,29 @@
+// Copyright © 2016 Alan A. A. Donovan & Brian W. Kernighan.
+// License: https://creativecommons.org/licenses/by-nc-sa/4.0/
+
+// See page 244.
+
+// Countdown implements the countdown for a rocket launch.
+package main
+
+import (
+	"fmt"
+	"time"
+)
+
+//!+
+func main() {
+	fmt.Println("Commencing countdown.")
+	tick := time.Tick(1 * time.Second)
+	for countdown := 10; countdown > 0; countdown-- {
+		fmt.Println(countdown)
+		<-tick
+	}
+	launch()
+}
+
+//!-
+
+func launch() {
+	fmt.Println("Lift off!")
+}