| // The purpose of this test is to demonstrate that duplicating dyn-compatible traits |
| // that are not auto-traits is rejected even though one could reasonably accept this. |
| |
| // Some arbitrary dyn-compatible 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() {} |
