graue.rs

use task::spawn;
use pipes::{stream, SharedChan};

fn main() {
    // Create port/channel pair for receiving/sending ints, respectively
    let (port, chan) = stream();
    // To allow multiple tasks to write, turn the channel into a SharedChan
    let chan = SharedChan(chan);

    fn doubler(x: int) -> int { x * 2 }

    // Spawn 3 tasks to process data in the background,
    // each writing to its own clone of the SharedChan
    let child = chan.clone();
    do spawn { child.send(doubler(10)); }
    let child = chan.clone();
    do spawn { child.send(doubler(20)); }
    let child = chan.clone();
    do spawn { child.send((|a: int, b: int| a + b)(30, 40)); }

    // Make port/channel pair for the string result
    let (result_port, result_chan) = stream();
    do spawn {
        let (x, y, z) = (port.recv(), port.recv(), port.recv());
        let result = fmt!("%d + %d + %d = %d", x, y, z, x+y+z);
        result_chan.send(result);
    }

    // Receive and print result
    io::println(result_port.recv());
}