// Copyright 2016 The Rust Project Developers. See the COPYRIGHT // file at the top-level directory of this distribution and at // http://rust-lang.org/COPYRIGHT. // // Licensed under the Apache License, Version 2.0 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. // Some traits can be derived for unions. #![feature(untagged_unions)] #[derive( Copy, Clone, Eq, )] union U { a: u8, b: u16, } impl PartialEq for U { fn eq(&self, rhs: &Self) -> bool { true } } #[derive( Clone, Copy, Eq )] union W { a: T, } impl PartialEq for W { fn eq(&self, rhs: &Self) -> bool { true } } fn main() { let u = U { b: 0 }; let u1 = u; let u2 = u.clone(); assert!(u1 == u2); let w = W { a: 0 }; let w1 = w.clone(); assert!(w == w1); }