| // Copyright 2014 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. |
| |
| use std::ops::Deref; |
| |
| struct MyPtr<'a>(&'a mut usize); |
| impl<'a> Deref for MyPtr<'a> { |
| type Target = usize; |
| |
| fn deref<'b>(&'b self) -> &'b usize { self.0 } |
| } |
| |
| trait Tr { |
| fn poke(&self, s: &mut usize); |
| } |
| |
| impl Tr for usize { |
| fn poke(&self, s: &mut usize) { |
| *s = 2; |
| } |
| } |
| |
| fn main() { |
| let s = &mut 1; |
| |
| MyPtr(s).poke(s); |
| //~^ ERROR cannot borrow `*s` as mutable more than once at a time |
| } |
