Go by Example: Range over Channels

In a previous example we saw how for and range provide iteration over basic data structures. We can also use this syntax to iterate over values received from a channel.

package main
import "fmt"
func main() {

We’ll iterate over 2 values in the queue channel.

    queue := make(chan string, 2)
    queue <- "one"
    queue <- "two"

This range iterates over each element as it’s received from queue. Because we closed the channel above, the iteration terminates after receiving the 2 elements.

    for elem := range queue {
$ go run range-over-channels.go

This example also showed that it’s possible to close a non-empty channel but still have the remaining values be received.

Next example: Timers.