filtermain.go

func main() {
  done := make(chan struct{})
  defer close(done)
  
  // Generates a channel sending integers
  // From 0 to 9
  range10 := rangeChannel(done, 10)
  
  isEven := func(x int) bool {
    return x % 2 == 0
  }
  for num := range Filter(done, range10, isEven) {
      fmt.Println(num)
  }
}