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
|
//@ run-pass
#![allow(dead_code, enum_intrinsics_non_enums)]
#![feature(variant_count)]
#![feature(never_type)]
use std::mem::variant_count;
enum Void {}
enum Foo {
A,
B,
C,
}
enum Bar {
A,
B,
C,
D(usize),
E { field_1: usize, field_2: Foo },
}
struct Baz {
a: u32,
b: *const u8,
}
const TEST_VOID: usize = variant_count::<Void>();
const TEST_FOO: usize = variant_count::<Foo>();
const TEST_BAR: usize = variant_count::<Bar>();
const NO_ICE_STRUCT: usize = variant_count::<Baz>();
const NO_ICE_BOOL: usize = variant_count::<bool>();
const NO_ICE_PRIM: usize = variant_count::<*const u8>();
fn main() {
assert_eq!(TEST_VOID, 0);
assert_eq!(TEST_FOO, 3);
assert_eq!(TEST_BAR, 5);
assert_eq!(variant_count::<Void>(), 0);
assert_eq!(variant_count::<Foo>(), 3);
assert_eq!(variant_count::<Bar>(), 5);
assert_eq!(variant_count::<Option<char>>(), 2);
assert_eq!(variant_count::<Option<!>>(), 2);
assert_eq!(variant_count::<Result<!, !>>(), 2);
}
|
