channelmux.go

package main

import (
	"fmt"
	"time"
)

func Mux(funcs []func(string)) chan string {
	ch := make(chan string)
	childrens := GetChannelsWriterForFuncs(funcs)
	go ChannelMux(ch, childrens)
	return ch
}

func GetChannelsWriterForFuncs(funcs []func(string)) []chan string {
	if len(funcs) == 0 {
		funcs = append(funcs, func(string) {})
	}
	childrenChan := []chan string{}
	for _, fn := range funcs {
		childChan := make(chan string)
		childrenChan = append(childrenChan, childChan)
		go ReadChanWithFunc(childChan, fn)
	}
	return childrenChan
}

func ReadChanWithFunc(ch chan string, fn func(string)) {
	for elem := range ch {
		fn(elem)
	}
	fn("dying")
}

func ChannelMux(from chan string, to []chan string) {
	for elem := range from {
		fmt.Println("sending elem", elem)
		for _, c := range to {
			c <- elem
		}
	}
	fmt.Println("killing children")
	for _, c := range to {
		close(c)
	}
}

func main() {
	ch := Mux([]func(string){
		func(s string) {
			fmt.Println("1", s)
		},
		func(s string) {
			fmt.Println("2", s)
		},
	})

	for i := 0; i < 10; i++ {
		ch <- fmt.Sprintf("step %d", i)
		time.Sleep(time.Second)
	}
	close(ch)

	time.Sleep(time.Second)
}