41 lines
901 B
Rust
41 lines
901 B
Rust
// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
|
|
// file at the top-level directory of this distribution and at
|
|
// http://rust-lang.org/COPYRIGHT.
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
|
|
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
|
|
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
|
|
// option. This file may not be copied, modified, or distributed
|
|
// except according to those terms.
|
|
|
|
struct dtor {
|
|
x: @mut int,
|
|
|
|
}
|
|
|
|
#[unsafe_destructor]
|
|
impl Drop for dtor {
|
|
fn drop(&self) {
|
|
// abuse access to shared mutable state to write this code
|
|
*self.x -= 1;
|
|
}
|
|
}
|
|
|
|
fn unwrap<T>(o: Option<T>) -> T {
|
|
match o {
|
|
Some(v) => v,
|
|
None => fail!()
|
|
}
|
|
}
|
|
|
|
pub fn main() {
|
|
let x = @mut 1;
|
|
|
|
{
|
|
let b = Some(dtor { x:x });
|
|
let _c = unwrap(b);
|
|
}
|
|
|
|
assert_eq!(*x, 0);
|
|
}
|