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
|
// The purpose of this test is to demonstrate that duplicating object safe traits
// that are not auto-traits is rejected even though one could reasonably accept this.
// Some arbitrary object-safe trait:
trait Obj {}
// Demonstrate that recursive expansion of trait aliases doesn't affect stable behavior:
type _0 = dyn Obj + Obj;
//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
// Some variations:
type _1 = dyn Send + Obj + Obj;
//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
type _2 = dyn Obj + Send + Obj;
//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
type _3 = dyn Obj + Send + Send; // But it is OK to duplicate auto traits.
// Take higher ranked types into account.
// Note that `'a` and `'b` are intentionally different to make sure we consider
// them semantically the same.
trait ObjL<'l> {}
type _4 = dyn for<'a> ObjL<'a> + for<'b> ObjL<'b>;
//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
trait ObjT<T> {}
type _5 = dyn ObjT<for<'a> fn(&'a u8)> + ObjT<for<'b> fn(&'b u8)>;
//~^ ERROR only auto traits can be used as additional traits in a trait object [E0225]
fn main() {}
|
