single-direction_single-channel.go

package main

import (
	"fmt"
)

func main() {
	n := 3

	// This is where we "make" the channel, which can be used to move the `int` datatype
	out := make(chan int)

	// We still run this function as a goroutine, but this time, the channel that we made is also provided
	go multiplyByTwo(n, out)

	// Blocking code: once any output is received on this channel, print it to the console and proceed
	fmt.Println(n, "multiplied by 2:", <-out)
}

// This function accepts a channel as its second argument...
func multiplyByTwo(num int, out chan<- int) {
	result := num * 2

	//... and pipes the result into it
	out <- result
}