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
|
// run-pass
#![allow(dead_code)]
#![allow(non_camel_case_types)]
#![allow(non_upper_case_globals)]
static tau: f64 = 2.0*3.14159265358979323;
struct Point {x: f64, y: f64}
struct Size {w: f64, h: f64}
enum shape {
circle(Point, f64),
rectangle(Point, Size)
}
fn compute_area(shape: &shape) -> f64 {
match *shape {
shape::circle(_, radius) => 0.5 * tau * radius * radius,
shape::rectangle(_, ref size) => size.w * size.h
}
}
impl shape {
// self is in the implicit self region
pub fn select<'r, T>(&self, threshold: f64, a: &'r T, b: &'r T)
-> &'r T {
if compute_area(self) > threshold {a} else {b}
}
}
fn select_based_on_unit_circle<'r, T>(
threshold: f64, a: &'r T, b: &'r T) -> &'r T {
let shape = &shape::circle(Point{x: 0.0, y: 0.0}, 1.0);
shape.select(threshold, a, b)
}
#[derive(Clone)]
struct thing {
x: A
}
#[derive(Clone)]
struct A {
a: isize
}
fn thing(x: A) -> thing {
thing {
x: x
}
}
impl thing {
pub fn bar(self: Box<thing>) -> isize { self.x.a }
pub fn quux(&self) -> isize { self.x.a }
pub fn baz<'a>(&'a self) -> &'a A { &self.x }
pub fn spam(self) -> isize { self.x.a }
}
trait Nus { fn f(&self); }
impl Nus for thing { fn f(&self) {} }
pub fn main() {
let y: Box<_> = Box::new(thing(A {a: 10}));
assert_eq!(y.clone().bar(), 10);
assert_eq!(y.quux(), 10);
let z = thing(A {a: 11});
assert_eq!(z.spam(), 11);
}
|