#![feature(plugin)] #![plugin(clippy)] #![deny(unit_cmp)] #![allow(no_effect, unnecessary_operation)] #[derive(PartialEq)] pub struct ContainsUnit(()); // should be fine fn main() { // this is fine if true == false { } // this warns if { true; } == { false; } { //~ERROR ==-comparison of unit values detected. This will always be true } if { true; } > { false; } { //~ERROR >-comparison of unit values detected. This will always be false } }