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Commit | Line | Data |
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b7449926 | 1 | // run-pass |
c34b1796 | 2 | |
1a4d82fc JJ |
3 | use std::rc::Rc; |
4 | use std::ops::Deref; | |
5 | ||
c34b1796 | 6 | #[derive(Copy, Clone)] |
1a4d82fc JJ |
7 | struct DerefWrapper<X, Y> { |
8 | x: X, | |
9 | y: Y | |
10 | } | |
11 | ||
1a4d82fc JJ |
12 | impl<X, Y> DerefWrapper<X, Y> { |
13 | fn get_x(self) -> X { | |
14 | self.x | |
15 | } | |
16 | } | |
17 | ||
18 | impl<X, Y> Deref for DerefWrapper<X, Y> { | |
19 | type Target = Y; | |
20 | ||
21 | fn deref(&self) -> &Y { | |
22 | &self.y | |
23 | } | |
24 | } | |
25 | ||
26 | mod priv_test { | |
27 | use std::ops::Deref; | |
28 | ||
c34b1796 | 29 | #[derive(Copy, Clone)] |
1a4d82fc JJ |
30 | pub struct DerefWrapperHideX<X, Y> { |
31 | x: X, | |
32 | pub y: Y | |
33 | } | |
34 | ||
1a4d82fc JJ |
35 | impl<X, Y> DerefWrapperHideX<X, Y> { |
36 | pub fn new(x: X, y: Y) -> DerefWrapperHideX<X, Y> { | |
37 | DerefWrapperHideX { | |
38 | x: x, | |
39 | y: y | |
40 | } | |
41 | } | |
42 | } | |
43 | ||
44 | impl<X, Y> Deref for DerefWrapperHideX<X, Y> { | |
45 | type Target = Y; | |
46 | ||
47 | fn deref(&self) -> &Y { | |
48 | &self.y | |
49 | } | |
50 | } | |
51 | } | |
52 | ||
53 | pub fn main() { | |
85aaf69f | 54 | let nested = DerefWrapper {x: true, y: DerefWrapper {x: 0, y: 1}}; |
1a4d82fc JJ |
55 | |
56 | // Use the first field that you can find. | |
57 | assert_eq!(nested.x, true); | |
58 | assert_eq!((*nested).x, 0); | |
59 | ||
60 | // Same for methods, even though there are multiple | |
61 | // candidates (at different nesting levels). | |
62 | assert_eq!(nested.get_x(), true); | |
63 | assert_eq!((*nested).get_x(), 0); | |
64 | ||
65 | // Also go through multiple levels of indirection. | |
66 | assert_eq!(Rc::new(nested).x, true); | |
67 | ||
85aaf69f | 68 | let nested_priv = priv_test::DerefWrapperHideX::new(true, DerefWrapper {x: 0, y: 1}); |
ea8adc8c | 69 | assert_eq!(nested_priv.x, 0); |
1a4d82fc JJ |
70 | assert_eq!((*nested_priv).x, 0); |
71 | } |