rust/src/test/compile-fail/borrowck-borrow-overloaded-deref-mut.rs
Alex Crichton 7858065113 std: Rename Chan/Port types and constructor
* Chan<T> => Sender<T>
* Port<T> => Receiver<T>
* Chan::new() => channel()
* constructor returns (Sender, Receiver) instead of (Receiver, Sender)
* local variables named `port` renamed to `rx`
* local variables named `chan` renamed to `tx`

Closes #11765
2014-03-13 13:23:29 -07:00

69 lines
1.5 KiB
Rust

// 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<T> for Own<T> {
fn deref<'a>(&'a self) -> &'a T {
unsafe { &*self.value }
}
}
impl<T> DerefMut<T> for Own<T> {
fn deref_mut<'a>(&'a mut self) -> &'a mut T {
unsafe { &mut *self.value }
}
}
fn deref_imm(x: Own<int>) {
let _i = &*x;
}
fn deref_mut1(x: Own<int>) {
let _i = &mut *x; //~ ERROR cannot borrow
}
fn deref_mut2(mut x: Own<int>) {
let _i = &mut *x;
}
fn deref_extend<'a>(x: &'a Own<int>) -> &'a int {
&**x
}
fn deref_extend_mut1<'a>(x: &'a Own<int>) -> &'a mut int {
&mut **x //~ ERROR cannot borrow
}
fn deref_extend_mut2<'a>(x: &'a mut Own<int>) -> &'a mut int {
&mut **x
}
fn assign1<'a>(x: Own<int>) {
*x = 3; //~ ERROR cannot borrow
}
fn assign2<'a>(x: &'a Own<int>) {
**x = 3; //~ ERROR cannot borrow
}
fn assign3<'a>(x: &'a mut Own<int>) {
**x = 3;
}
pub fn main() {}