src/test/run-pass/uniq-self-in-mut-slot.rs

   1 // Copyright 2013 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11
  12 #![allow(unknown_features)]
  13 #![feature(box_syntax)]
  14
  15 struct X {
  16     a: isize
  17 }
  18
  19 trait Changer {
  20     fn change(self: Box<Self>) -> Box<Self>;
  21 }
  22
  23 impl Changer for X {
  24     fn change(mut self: Box<X>) -> Box<X> {
  25         self.a = 55;
  26         self
  27     }
  28 }
  29
  30 pub fn main() {
  31     let x: Box<_> = box X { a: 32 };
  32     let new_x = x.change();
  33     assert_eq!(new_x.a, 55);
  34 }