// 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 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. #[feature(managed_boxes)]; use std::cell::Cell; struct r { b: @Cell, } #[unsafe_destructor] impl Drop for r { fn drop(&mut self) { self.b.set(self.b.get() + 1); } } fn r(b: @Cell) -> r { r { b: b } } pub fn main() { let b = @Cell::new(0); { let _p = Some(r(b)); } assert_eq!(b.get(), 1); }