Channels are a typed conduit through which you can send and receive values with the channel operator, <-.

ch <- v    // Send v to channel ch.v := <-ch  // Receive from ch, and           // assign value to v.

(The data flows in the direction of the arrow.)

Like maps and slices, channels must be created before use:

ch := make(chan int)

By default, sends and receives block until the other side is ready. This allows goroutines to synchronize without explicit locks or condition variables.

package mainimport "fmt"func sum(a []int, c chan int) {    sum := 0    for _, v := range a {        sum += v    }    c <- sum //send sum to c}func main() {    a := []int{7, 2, 8, -9, 4, 0}    c := make(chan int)    go sum(a[:len(a)/2], c)    go sum(a[len(a)/2:], c)    x, y := <-c,  <-c     fmt.Println(x, y, x + y)}

A Tour of Go Channels