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//@ run-pass
#![allow(dead_code)]
#![allow(non_snake_case)]
use std::ops::Add;
trait Positioned<S> {
fn SetX(&mut self, _: S);
fn X(&self) -> S;
}
trait Movable<S: Add<Output=S>>: Positioned<S> {
fn translate(&mut self, dx: S) {
let x = self.X() + dx;
self.SetX(x);
}
}
struct Point { x: isize, y: isize }
impl Positioned<isize> for Point {
fn SetX(&mut self, x: isize) {
self.x = x;
}
fn X(&self) -> isize {
self.x
}
}
impl Movable<isize> for Point {}
pub fn main() {
let mut p = Point{ x: 1, y: 2};
p.translate(3);
assert_eq!(p.X(), 4);
}
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