// 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 // Send the sequence 2, 3, 4, ... to channel 'ch'. func Generate(ch chan int) { for i := 2; ; i++ { ch <- i // Send 'i' to channel 'ch'. } } // Copy the values from channel 'in' to channel 'out', // removing those divisible by 'prime'. func Filter(in, out chan int, prime int) { for { i := <-in; // Receive value of new variable 'i' from 'in'. if i % prime != 0 { out <- i // Send 'i' to channel 'out'. } } } // The prime sieve: Daisy-chain Filter processes together. func main() { ch := make(chan int); // Create a new channel. go Generate(ch); // Start Generate() as a goroutine. for { prime := <-ch; print(prime, "\n"); ch1 := make(chan int); go Filter(ch, ch1, prime); ch = ch1 } }