mirror of
https://github.com/rust-lang/rust.git
synced 2024-10-31 22:41:50 +00:00
32 lines
657 B
Rust
32 lines
657 B
Rust
// 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);
|
|
}
|