rust/tests/ui/borrowck/borrowck-loan-rcvr-overloaded-op.rs
2023-01-11 09:32:08 +00:00

47 lines
743 B
Rust

use std::ops::Add;
#[derive(Copy, Clone)]
struct Point {
x: isize,
y: isize,
}
impl Add<isize> for Point {
type Output = isize;
fn add(self, z: isize) -> isize {
self.x + self.y + z
}
}
impl Point {
pub fn times(&self, z: isize) -> isize {
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 use `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 main() {
}