1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
|
// 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 <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.
#![feature(box_syntax)]
use std::cell::Cell;
// Resources can't be copied, but storing into data structures counts
// as a move unless the stored thing is used afterwards.
struct r<'a> {
i: &'a Cell<isize>,
}
struct BoxR<'a> { x: r<'a> }
impl<'a> Drop for r<'a> {
fn drop(&mut self) {
self.i.set(self.i.get() + 1)
}
}
fn r(i: &Cell<isize>) -> r {
r {
i: i
}
}
fn test_rec() {
let i = &Cell::new(0);
{
let _a = BoxR {x: r(i)};
}
assert_eq!(i.get(), 1);
}
fn test_tag() {
enum t<'a> {
t0(r<'a>),
}
let i = &Cell::new(0);
{
let _a = t::t0(r(i));
}
assert_eq!(i.get(), 1);
}
fn test_tup() {
let i = &Cell::new(0);
{
let _a = (r(i), 0);
}
assert_eq!(i.get(), 1);
}
fn test_unique() {
let i = &Cell::new(0);
{
let _a: Box<_> = box r(i);
}
assert_eq!(i.get(), 1);
}
fn test_unique_rec() {
let i = &Cell::new(0);
{
let _a: Box<_> = box BoxR {
x: r(i)
};
}
assert_eq!(i.get(), 1);
}
pub fn main() {
test_rec();
test_tag();
test_tup();
test_unique();
test_unique_rec();
}
|
