src/test/ui/type-alias-impl-trait/issue-63677-type-alias-coherence.rs

   1 // check-pass
   2 // Regression test for issue #63677 - ensure that
   3 // coherence checking can properly handle 'impl trait'
   4 // in type aliases
   5 #![feature(type_alias_impl_trait)]
   6
   7 pub trait Trait {}
   8 pub struct S1<T>(T);
   9 pub struct S2<T>(T);
  10
  11 pub type T1 = impl Trait;
  12 pub type T2 = S1<T1>;
  13 pub type T3 = S2<T2>;
  14
  15 impl<T> Trait for S1<T> {}
  16 impl<T: Trait> S2<T> {}
  17 impl T3 {}
  18
  19 pub fn use_t1() -> T1 { S1(()) }
  20
  21 fn main() {}