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//@ run-pass
#![feature(box_patterns)]
use std::ops::{Deref, DerefMut};
struct X(Box<isize>);
static mut DESTRUCTOR_RAN: bool = false;
impl Drop for X {
fn drop(&mut self) {
unsafe {
assert!(!DESTRUCTOR_RAN);
DESTRUCTOR_RAN = true;
}
}
}
impl Deref for X {
type Target = isize;
fn deref(&self) -> &isize {
let &X(box ref x) = self;
x
}
}
impl DerefMut for X {
fn deref_mut(&mut self) -> &mut isize {
let &mut X(box ref mut x) = self;
x
}
}
fn main() {
{
let mut test = X(Box::new(5));
{
let mut change = || { *test = 10 };
change();
}
assert_eq!(*test, 10);
}
assert!(unsafe { DESTRUCTOR_RAN });
}
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