Kanallarni funksiya parametrlarida ishlatganda, kanal faqat yuborish (send-only) yoki faqat qabul qilish (receive-only) uchun ekanini ko'rsatish mumkin. Bu dastur tip xavfsizligini oshiradi.

package main

import "fmt"

// ping faqat yuborish uchun mo'ljallangan kanal qabul qiladi (chan<-)
// Bu kanaldan qabul qilishga urinish kompilyatsiya xatosi bo'ladi
func ping(pings chan<- string, msg string) {
    pings <- msg
}

// pong — bitta qabul qilish (<-chan) va bitta yuborish (chan<-) kanalini oladi
func pong(pings <-chan string, pongs chan<- string) {
    msg := <-pings
    pongs <- msg
}

func main() {
    pings := make(chan string, 1)
    pongs := make(chan string, 1)

    ping(pings, "passed message")
    pong(pings, pongs)

    fmt.Println(<-pongs)
}

Terminalda bajarish:

$ go run channel-directions.go
passed message