Go example of joining / merging a slice of arbitrary length into one chanel

channel_join.go

package main

import (
	"fmt"
)

func setupChans(count int) []chan int {
	c := []chan int{}

	for i := 0; i < count; i++ {
		newChan := make(chan int)
		c = append(c, newChan)

		go func(num int, cn chan int) {
			for j := 0; j < 4; j++ {
				cn <- j*count + num
			}
			close(cn)
		}(i, newChan)
	}

	return c
}

func joinChannels(chans []chan int) chan int {
	joint := make(chan int)
	closeChan := make(chan bool)

	for _, c := range chans {
		go func(inChan chan int) {
			for i := range inChan {
				joint <- i
			}
			closeChan <- true
		}(c)
	}

	go func() {
		for i := 0; i < len(chans); i++ {
			<-closeChan
		}
		close(joint)
	}()

	return joint
}

func main() {
	count := 4

	chans := setupChans(count)

	master := joinChannels(chans)

	for i := range master {
		fmt.Printf("%v\n", i)
	}
}