Exit a for loop using channel

main.go

package main

import (
	"fmt"
	"time"
)

func main() {

	function2()
	for {
		fmt.Println("this is main function")
		time.Sleep(1 * time.Second)
	}
}

func function2() {
	function3()
	fmt.Println("function2 exit")
}

func function3() {
	q := make(chan bool)
	go func() {
		for {
			select {
			case <-q:
				fmt.Println("EXIT")
				return
			default:
				fmt.Println("yeet")
				time.Sleep(1 * time.Second)
			}

		}
	}()
	go func() {
		for {
			select {
			case <-q:
				fmt.Println("EXIT 2")
				return
			default:
				fmt.Println("yeet 2")
				time.Sleep(2 * time.Second)
			}

		}
	}()
	time.Sleep(5 * time.Second)
	fmt.Println("closing channel q")
	close(q)
	return
}

It took me time to realize that goroutine exit when the MAIN function exit, not the CALLER function exit. In this example, I had a goroutine that running an infinite for loop, with for loop. select could achieve the same behavior while also I can trigger it to exit by using channel.