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
|
//@ run-pass
// This file checks that `PhantomData` is considered structurally matchable.
use std::marker::PhantomData;
fn main() {
let mut count = 0;
// A type which is not structurally matchable:
struct NotSM;
// And one that is:
#[derive(PartialEq, Eq)]
struct SM;
// Check that SM is structural-match:
const CSM: SM = SM;
match SM {
CSM => count += 1,
};
// Check that PhantomData<T> is structural-match even if T is not.
const CPD1: PhantomData<NotSM> = PhantomData;
match PhantomData {
CPD1 => count += 1,
};
// Check that PhantomData<T> is structural-match when T is.
const CPD2: PhantomData<SM> = PhantomData;
match PhantomData {
CPD2 => count += 1,
};
// Check that a type which has a PhantomData is structural-match.
#[derive(PartialEq, Eq, Default)]
struct Foo {
alpha: PhantomData<NotSM>,
beta: PhantomData<SM>,
}
const CFOO: Foo = Foo {
alpha: PhantomData,
beta: PhantomData,
};
match Foo::default() {
CFOO => count += 1,
};
// Final count must be 4 now if all
assert_eq!(count, 4);
}
|
