1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
|
//@ run-pass
#![allow(non_camel_case_types)]
use std::cell::Cell;
struct shrinky_pointer<'a> {
i: &'a Cell<isize>,
}
impl<'a> Drop for shrinky_pointer<'a> {
fn drop(&mut self) {
println!("Hello!"); self.i.set(self.i.get() - 1);
}
}
impl<'a> shrinky_pointer<'a> {
pub fn look_at(&self) -> isize { return self.i.get(); }
}
fn shrinky_pointer(i: &Cell<isize>) -> shrinky_pointer {
shrinky_pointer {
i: i
}
}
pub fn main() {
let my_total = &Cell::new(10);
{ let pt = shrinky_pointer(my_total); assert_eq!(pt.look_at(), 10); }
println!("my_total = {}", my_total.get());
assert_eq!(my_total.get(), 9);
}
|
