| // 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 <LICENSE-APACHE or |
| // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license |
| // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your |
| // option. This file may not be copied, modified, or distributed |
| // except according to those terms. |
| |
| macro_rules! not_an_lvalue { |
| ($thing:expr) => { |
| $thing = 42; |
| //~^ ERROR invalid left-hand side expression |
| } |
| } |
| |
| fn main() { |
| not_an_lvalue!(99); |
| //~^ NOTE in this expansion of not_an_lvalue! |
| } |
