func worker(id int, jobs <-chan int, results chan<- int) {
for j := range jobs {
fmt.Println("worker", id, "processing job", j)
time.Sleep(time.Second)
results <- j * 2
}
}
func main() {
t := time.Now()
fmt.Println(t)
jobs := make(chan int, 100)
results := make(chan int, 100)
for w := 1; w <= 4; w++ {
go worker(w, jobs, results)
}
for j := 1; j <= 20; j++ {
jobs <- j
}
close(jobs)
for a := 1; a <= 20; a++ {
<-results
}
t = time.Now()
fmt.Println(t)
}
I am confused of the "<-" and I can not find any related documents about "<-". So what is the difference between <- and =?? why I can not use = here?