GO by example, part 4

5-go-by-example/31-closing-channels.go

@@ -0,0 +1,36 @@
+// closing a channel indicates that no more values will be sent on it
+package main
+
+import "fmt"
+
+func main() {
+	// jobs channel to communicate work to be done
+	jobs := make(chan int, 5)
+	done := make(chan bool)
+
+	// repeatedly receives from jobs
+	// more value will be false if jobs has been closed and all values in the channel have already been received
+	go func() {
+		for {
+			j, more := <-jobs
+			if more {
+				fmt.Println("received job", j)
+			} else {
+				fmt.Println("received all jobs")
+				done <- true
+				return
+			}
+		}
+	}()
+
+	// sends 3 jobs to the worker over the jobs channel, then closes it
+	for j := 1; j <= 3; j++ {
+		jobs <- j
+		fmt.Println("sent job", j)
+	}
+	close(jobs)
+	fmt.Println("sent all jobs")
+
+	// await the worker using the synchronization approach
+	<-done
+}