blob: 567f5d9bb6876ef7c9de39ebc46e1f5c6a757a7d [file] [log] [blame]
// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package main
import "fmt"
// Send the sequence 2, 3, 4, ... to returned channel
func generate() chan int {
ch := make(chan int);
go func(ch chan int){
for i := 2; ; i++ {
ch <- i
}
}(ch);
return ch;
}
// Filter out input values divisible by 'prime', send rest to returned channel
func filter(in chan int, prime int) chan int {
out := make(chan int);
go func(in chan int, out chan int, prime int) {
for {
if i := <-in; i % prime != 0 {
out <- i
}
}
}(in, out, prime);
return out;
}
func sieve() chan int {
out := make(chan int);
go func(out chan int) {
ch := generate();
for {
prime := <-ch;
out <- prime;
ch = filter(ch, prime);
}
}(out);
return out;
}
func main() {
primes := sieve();
for {
fmt.Println(<-primes);
}
}