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"
    close(queue)

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 {
        fmt.Println(elem)
    }
}
 
$ go run range-over-channels.go
one
two

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.

by Mark McGranaghan and Eli Bendersky | source | license