1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
|
// Tests that we cannot assume that an opaque type does *not* implement some
// other trait
#![feature(type_alias_impl_trait)]
trait OpaqueTrait {}
impl<T> OpaqueTrait for T {}
type OpaqueType = impl OpaqueTrait;
#[define_opaque(OpaqueType)]
fn mk_opaque() -> OpaqueType {
()
}
#[derive(Debug)]
struct D<T>(T);
trait AnotherTrait {}
impl<T: std::fmt::Debug> AnotherTrait for T {}
// This is in error, because we cannot assume that `OpaqueType: !Debug`
impl AnotherTrait for D<OpaqueType> {
//~^ ERROR conflicting implementations of trait `AnotherTrait` for type `D<_>`
}
fn main() {}
|
