| // Copyright 2014 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. |
| |
| |
| #![allow(unknown_features)] |
| #![feature(box_syntax)] |
| #![feature(box_patterns)] |
| #![feature(unboxed_closures)] |
| |
| 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 5); |
| { |
| let mut change = || { *test = 10 }; |
| change(); |
| } |
| assert_eq!(*test, 10); |
| } |
| assert!(unsafe { DESTRUCTOR_RAN }); |
| } |