blob: 15540cb460e7a6a29994e374eaabbf1a4d44712b (
plain)
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
|
// Nested impl-traits can impose different member constraints on the same region variable.
// check-pass
trait Cap<'a> {}
impl<T> Cap<'_> for T {}
// Assuming the hidden type is `[&'_#15r u8; 1]`, we have two distinct member constraints:
// - '_#15r member ['static, 'a, 'b] // from outer impl-trait
// - '_#15r member ['static, 'a] // from inner impl-trait
// To satisfy both we can only choose 'a.
fn pass_early_bound<'s, 'a, 'b>(a: &'s u8) -> impl IntoIterator<Item = impl Cap<'a>> + Cap<'b>
where
's: 'a,
's: 'b,
{
[a]
}
// Same as the above but with late-bound regions.
fn pass_late_bound<'s, 'a, 'b>(
a: &'s u8,
_: &'a &'s u8,
_: &'b &'s u8,
) -> impl IntoIterator<Item = impl Cap<'a>> + Cap<'b> {
[a]
}
fn main() {}
|
