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// 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.
struct Point {
x: int,
y: int,
}
impl Add<int,int> for Point {
fn add(&self, z: &int) -> int {
self.x + self.y + (*z)
}
}
impl Point {
pub fn times(&self, z: int) -> int {
self.x * self.y * z
}
}
fn a() {
let mut p = Point {x: 3, y: 4};
// ok (we can loan out rcvr)
p + 3;
p.times(3);
}
fn b() {
let mut p = Point {x: 3, y: 4};
// Here I create an outstanding loan and check that we get conflicts:
let q = &mut p;
p + 3; //~ ERROR cannot borrow `p`
p.times(3); //~ ERROR cannot borrow `p`
*q + 3; // OK to use the new alias `q`
q.x += 1; // and OK to mutate it
}
fn c() {
// Here the receiver is in aliased memory but due to write
// barriers we can still consider it immutable.
let q = @mut Point {x: 3, y: 4};
*q + 3;
q.times(3);
}
fn main() {
}
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