rust/tests/ui/traits/superdefault-generics.rs

40 lines
706 B
Rust

//@ run-pass
#![allow(dead_code)]
#![allow(non_snake_case)]
// There is some other borrowck bug, so we make the stuff not mut.
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<S> { x: S, y: S }
impl<S: Clone> Positioned<S> for Point<S> {
fn SetX(&mut self, x: S) {
self.x = x;
}
fn X(&self) -> S {
self.x.clone()
}
}
impl<S: Clone + Add<Output=S>> Movable<S> for Point<S> {}
pub fn main() {
let mut p = Point{ x: 1, y: 2};
p.translate(3);
assert_eq!(p.X(), 4);
}