| // Copyright 2012 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. |
| |
| |
| trait Positioned { |
| fn SetX(&mut self, _: isize); |
| fn X(&self) -> isize; |
| } |
| |
| trait Movable: Positioned { |
| fn translate(&mut self, dx: isize) { |
| let x = self.X(); |
| self.SetX(x + dx); |
| } |
| } |
| |
| struct Point { x: isize, y: isize } |
| |
| impl Positioned for Point { |
| fn SetX(&mut self, x: isize) { |
| self.x = x; |
| } |
| fn X(&self) -> isize { |
| self.x |
| } |
| } |
| |
| impl Movable for Point {} |
| |
| pub fn main() { |
| let mut p = Point{ x: 1, y: 2}; |
| p.translate(3); |
| assert_eq!(p.X(), 4); |
| } |
