src/test/run-pass/overloaded-deref.rs

   1 // Copyright 2014 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 #![feature(collections)]
  12
  13 use std::cell::RefCell;
  14 use std::rc::Rc;
  15 use std::string::String;
  16
  17 #[derive(PartialEq, Debug)]
  18 struct Point {
  19     x: isize,
  20     y: isize
  21 }
  22
  23 pub fn main() {
  24     assert_eq!(*Rc::new(5), 5);
  25     assert_eq!(***Rc::new(Box::new(Box::new(5))), 5);
  26     assert_eq!(*Rc::new(Point {x: 2, y: 4}), Point {x: 2, y: 4});
  27
  28     let i = Rc::new(RefCell::new(2));
  29     let i_value = *(*i).borrow();
  30     *(*i).borrow_mut() = 5;
  31     assert_eq!((i_value, *(*i).borrow()), (2, 5));
  32
  33     let s = Rc::new("foo".to_string());
  34     assert_eq!(*s, "foo".to_string());
  35     assert_eq!((*s), "foo");
  36
  37     let mut_s = Rc::new(RefCell::new(String::from("foo")));
  38     (*(*mut_s).borrow_mut()).push_str("bar");
  39     // assert_eq! would panic here because it stores the LHS and RHS in two locals.
  40     assert_eq!((*(*mut_s).borrow()), "foobar");
  41     assert_eq!((*(*mut_s).borrow_mut()), "foobar");
  42
  43     let p = Rc::new(RefCell::new(Point {x: 1, y: 2}));
  44     (*(*p).borrow_mut()).x = 3;
  45     (*(*p).borrow_mut()).y += 3;
  46     assert_eq!(*(*p).borrow(), Point {x: 3, y: 5});
  47
  48     let v = Rc::new(RefCell::new(vec!(1, 2, 3)));
  49     (*(*v).borrow_mut())[0] = 3;
  50     (*(*v).borrow_mut())[1] += 3;
  51     assert_eq!(((*(*v).borrow())[0],
  52                 (*(*v).borrow())[1],
  53                 (*(*v).borrow())[2]), (3, 5, 3));
  54 }