cracklepop.go

// A concurrent CracklePop Program

package main

import (
	"fmt"
)

// Create a goroutine that sends infinite empty string on a channel
// and returns the channel
func generate() chan string {
	c := make(chan string)
	go func() {
		for {
			c <- ""
		}
	}()
	return c
}

// Creates a goroutine that takes a channel and modifies it so that
// it returns a string s on the new after every x incoming messages on the channel.
// The function returns a new channel
func filter(c chan string, x int, s string) chan string {
	ch := make(chan string)
	go func() {
		count := 0
		for {
			i := <-c
			count += 1
			if count%x == 0 {
				ch <- i + s
				count = 0
			} else {
				ch <- i
			}
		}
	}()
	return ch
}

func main() {
	// create a goroutine that sends infinite empty strings on c
	c := generate()

	// create a goroutine that modifies channel c to add Crackle
	// to the string after every 3 string
	c1 := filter(c, 3, "Crackle")

	// create a goroutine that modifies channel c1 to add Pop to the
	// string after every 5 strings
	c2 := filter(c1, 5, "Pop")

	for i := 1; i <= 100; i++ {
		if s := <-c2; s != "" {
			fmt.Printf("%s\n", s)
		} else {
			fmt.Printf("%d\n", i)
		}
	}
}