mirror of
https://github.com/rust-lang/rust.git
synced 2024-11-23 23:34:48 +00:00
33 lines
829 B
Rust
33 lines
829 B
Rust
fn borrow_mut<T>(x: &mut T) -> &mut T { x }
|
|
fn borrow<T>(x: &T) -> &T { x }
|
|
|
|
fn borrow_mut2<T>(_: &mut T, _: &mut T) {}
|
|
fn borrow2<T>(_: &mut T, _: &T) {}
|
|
|
|
fn double_mut_borrow<T>(x: &mut Box<T>) {
|
|
let y = borrow_mut(x);
|
|
let z = borrow_mut(x);
|
|
//~^ ERROR cannot borrow `*x` as mutable more than once at a time
|
|
drop((y, z));
|
|
}
|
|
|
|
fn double_imm_borrow(x: &mut Box<i32>) {
|
|
let y = borrow(x);
|
|
let z = borrow(x);
|
|
**x += 1;
|
|
//~^ ERROR cannot assign to `**x` because it is borrowed
|
|
drop((y, z));
|
|
}
|
|
|
|
fn double_mut_borrow2<T>(x: &mut Box<T>) {
|
|
borrow_mut2(x, x);
|
|
//~^ ERROR cannot borrow `*x` as mutable more than once at a time
|
|
}
|
|
|
|
fn double_borrow2<T>(x: &mut Box<T>) {
|
|
borrow2(x, x);
|
|
//~^ ERROR cannot borrow `*x` as mutable because it is also borrowed as immutable
|
|
}
|
|
|
|
pub fn main() {}
|