gistfile1.txt

mod shared_cache {
    tag response[K, V] { 
        not_found(K);
        found(K, V);
    }

    tag command[K, V] {
        put_item(K, V);
        get_item(K, chan[response[K,V]]);
        quit;
    }

    type proxy[K, V] = obj {
    };

    fn cache_server[K, V] (chan[chan[command[K,V]]] c) {
        let port[command[K,V]] ctrl = port();
        c <| chan(ctrl);
        while(true) {
            auto cmd;
            ctrl |> cmd;
            alt(cmd) {
                case(put_item(?key, ?val)) {
                    fail
                }
                case(get_item(?key, ?out)) {
                    fail
                }
                case(quit) {
                    break;
                }
            }
        }
        log_err "Cache server exiting"
    }

    fn start_server[K, V]() -> chan[command[K,V]] {
        let port[chan[command[K, V]]] p = port();
        
        // Uh oh... this exposes issues with the task lifetime system.
        spawn cache_server(chan(p));

        auto c;
        p |> c;
        
        ret c;
    }
}