extern crate futures; // 0.1.28
extern crate tokio; // 0.1.22

use std::time::Duration;
use futures::Stream;
use tokio::timer::DelayQueue;

fn main() {
   let mut times1 = DelayQueue::new();
   times1.insert(1, Duration::new(3, 0));
   times1.insert(2, Duration::new(3, 0));

   for time in times1.wait() {
      dbg!(time);
   }
}