error[E0433]: failed to resolve: `Self` is only available in impls, traits, and type definitions
  --> $DIR/use-self-type.rs:7:16
   |
LL |         pub(in Self::f) struct Z;
   |                ^^^^ `Self` is only available in impls, traits, and type definitions

error[E0432]: unresolved import `Self`
  --> $DIR/use-self-type.rs:6:13
   |
LL |         use Self::f;
   |             ^^^^ `Self` is only available in impls, traits, and type definitions

error: aborting due to 2 previous errors

Some errors have detailed explanations: E0432, E0433.
For more information about an error, try `rustc --explain E0432`.