// +build ignore,OMIT package main import "fmt" // 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(src <-chan int, dst chan<- int, prime int) { for i := range src { // Loop over values received from 'src'. if i%prime != 0 { dst <- i; // Send 'i' to channel 'dst'. } } } // BREAK OMIT // The prime sieve: Daisy-chain filter processes together. func sieve() { ch := make(chan int); // Create a new channel. go generate(ch); // Start generate() as a subprocess. for { prime := <-ch; fmt.Print(prime, "\n"); ch1 := make(chan int); go filter(ch, ch1, prime); ch = ch1; } } func main() { sieve(); }