Example
func bufferedUnbufferedExample(buffered bool) {
// We'll declare the channel, and we'll make it buffered or
// unbuffered depending on the parameter `buffered` passed
// to this function.
var ch chan int
if buffered {
ch = make(chan int, 3)
} else {
ch = make(chan int)
}
// We'll start a goroutine, which will emulate a webserver
// receiving tasks to do every 25ms.
go func() {
for i := 0; i < 7; i++ {
// If the channel is buffered, then while there's an empty
// "slot" in the channel, sending to it will not be a
// blocking operation. If the channel is full, however, we'll
// have to wait until a "slot" frees up.
// If the channel is unbuffered, sending will block until
// there's a receiver ready to take the value. This is great
// for goroutine synchronization, not so much for queueing
// tasks for instance in a webserver, as the request will
// hang until the worker is ready to take our task.
fmt.Println(">", "Sending", i, "...")
ch <- i
fmt.Println(">", i, "sent!")
time.Sleep(25 * time.Millisecond)
}
// We'll close the channel, so that the range over channel
// below can terminate.
close(ch)
}()
for i := range ch {
// For each task sent on the channel, we would perform some
// task. In this case, we will assume the job is to
// "sleep 100ms".
fmt.Println("<", i, "received, performing 100ms job")
time.Sleep(100 * time.Millisecond)
fmt.Println("<", i, "job done")
}
}
go playground
