type-qualifier-1.go

package main

import (
	"fmt"
	"time"
)

func producer(ch chan<- int) {
	ch <- 0
}

func producer_bad(ch chan<- int) {
	consumer(ch)
}

func consumer(ch <-chan int) {
	fmt.Println("consumed %d", <-ch)
}

func main() {
	ch := make(chan int)

	go producer(ch)
	go producer_bad(ch)

	time.Sleep(1 * time.Second)
}