Code shared from the Rust Playground

playground.rs

extern crate tokio; // 0.1.8;
extern crate futures; // 0.1.24;

use futures::sync::mpsc;
use futures::{task, Async, Future, Sink, Stream};

pub fn invoke_bpm_battle_warm_up( // this method is called from the poll parent method
    receiver: &mut Option<mpsc::Receiver<bool>>,
    msg: BattleWarmUp,
    addr: Addr<Bpm>,
) {
    let _ = receiver.get_or_insert_with(|| {
        let (tx, rx) = mpsc::channel::<bool>(1);
        let future = addr
            .send(msg)
            .map_err(Into::into)
            .and_then(|r| r)
            .map_err(|_| format_err!("mpsc send error"))
            .and_then(move |b| { 
                tx.send(b)
                    .map_err(|_| format_err!("mpsc receive error"))
                    .map(|_| ())
            }).map_err(|_| ());

        let _ = tokio::spawn(future);
        rx
    });
}