...
Run Format

Source file test/sieve.go

Documentation: test

  // build
  
  // 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.
  
  // Test basic concurrency: the classic prime sieve.
  // Do not run - loops forever.
  
  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 <-chan int, 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 Sieve() {
  	ch := make(chan int) // Create a new channel.
  	go Generate(ch)      // Start Generate() as a subprocess.
  	for {
  		prime := <-ch
  		print(prime, "\n")
  		ch1 := make(chan int)
  		go Filter(ch, ch1, prime)
  		ch = ch1
  	}
  }
  
  func main() {
  	Sieve()
  }
  

View as plain text