| // 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. |
| |
| // Test how overloaded deref interacts with borrows when DerefMut |
| // is implemented. |
| |
| use std::ops::{Deref, DerefMut}; |
| |
| struct Own<T> { |
| value: *mut T |
| } |
| |
| impl<T> Deref for Own<T> { |
| type Target = T; |
| |
| fn deref<'a>(&'a self) -> &'a T { |
| unsafe { &*self.value } |
| } |
| } |
| |
| impl<T> DerefMut for Own<T> { |
| fn deref_mut<'a>(&'a mut self) -> &'a mut T { |
| unsafe { &mut *self.value } |
| } |
| } |
| |
| fn deref_imm(x: Own<isize>) { |
| let __isize = &*x; |
| } |
| |
| fn deref_mut1(x: Own<isize>) { |
| let __isize = &mut *x; //~ ERROR cannot borrow |
| } |
| |
| fn deref_mut2(mut x: Own<isize>) { |
| let __isize = &mut *x; |
| } |
| |
| fn deref_extend<'a>(x: &'a Own<isize>) -> &'a isize { |
| &**x |
| } |
| |
| fn deref_extend_mut1<'a>(x: &'a Own<isize>) -> &'a mut isize { |
| &mut **x //~ ERROR cannot borrow |
| } |
| |
| fn deref_extend_mut2<'a>(x: &'a mut Own<isize>) -> &'a mut isize { |
| &mut **x |
| } |
| |
| fn assign1<'a>(x: Own<isize>) { |
| *x = 3; //~ ERROR cannot borrow |
| } |
| |
| fn assign2<'a>(x: &'a Own<isize>) { |
| **x = 3; //~ ERROR cannot borrow |
| } |
| |
| fn assign3<'a>(x: &'a mut Own<isize>) { |
| **x = 3; |
| } |
| |
| pub fn main() {} |