#![feature(plugin)] #![plugin(clippy)] #![warn(clippy)] #![allow(unused)] fn the_answer(ref mut x: u8) { *x = 42; } fn main() { let mut x = 0; the_answer(x); // Closures should not warn let y = |ref x| { println!("{:?}", x) }; y(1u8); let ref x = 1; let ref y: (&_, u8) = (&1, 2); let ref z = 1 + 2; let ref mut z = 1 + 2; let (ref x, _) = (1,2); // okay, not top level println!("The answer is {}.", x); }