// Copyright 2013 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. #![allow(unknown_features)] #![feature(box_syntax)] struct X { a: isize } trait Changer : Sized { fn change(mut self) -> Self { self.set_to(55); self } fn change_again(mut self: Box) -> Box { self.set_to(45); self } fn set_to(&mut self, a: isize); } impl Changer for X { fn set_to(&mut self, a: isize) { self.a = a; } } pub fn main() { let x = X { a: 32 }; let new_x = x.change(); assert_eq!(new_x.a, 55); let x: Box<_> = box new_x; let new_x = x.change_again(); assert_eq!(new_x.a, 45); }