gistfile1.txt

use std::sync::{Arc, Mutex};
use std::sync::mpsc::*;

fn main() {
    let (tx, rx):(Sender<_>, Receiver<_>) = channel();
}

src/main.rs:21:18: 21:42 error: unable to infer enough type information about `_`; type annotations or generic parameter binding required [E0282]
src/main.rs:21     let (tx, rx):(Sender<_>, Receiver<_>) = channel(); //???????
                                ^~~~~~~~~~~~~~~~~~~~~~~~