channel_worker.ion

// Channel worker: main sends job ids on a channel; a spawned thread sums them and replies.

fn job_count() -> int {
    return 5;
}

fn main() -> int {
    let (job_tx, job_rx): (Sender<int>, Receiver<int>) = channel<int>();
    let (done_tx, done_rx): (Sender<int>, Receiver<int>) = channel<int>();

    spawn {
        let mut rx: Receiver<int> = job_rx;
        let mut sum: int = 0;
        let mut received: int = 0;
        loop {
            if received >= job_count() {
                break;
            }
            let job: int = recv(&mut rx);
            sum = sum + job;
            received = received + 1;
        }
        send(&done_tx, sum);
    };

    let mut next_job: int = 1;
    while next_job <= job_count() {
        send(&job_tx, next_job);
        next_job = next_job + 1;
    }

    let mut done_rx_mut: Receiver<int> = done_rx;
    let total: int = recv(&mut done_rx_mut);

    if total != 15 {
        return 1;
    }
    return 0;
}