| //@ check-pass |
| //@ revisions: current next |
| //@ ignore-compare-mode-next-solver (explicit revisions) |
| //@[next] compile-flags: -Znext-solver |
| |
| trait Proj<'a> { |
| type Assoc; |
| } |
| |
| impl<'a, 'b, F: FnOnce() -> &'b ()> Proj<'a> for F { |
| type Assoc = (); |
| } |
| |
| fn is_proj<F: for<'a> Proj<'a>>(f: F) {} |
| |
| fn define<'a>() -> impl Sized + use<'a> { |
| // This defines the RPIT to `&'unconstrained_b ()`, an inference |
| // variable which is in a higher universe as gets created inside |
| // of the binder of `F: for<'a> Proj<'a>`. This previously caused |
| // us to not apply member constraints. |
| // |
| // This was unnecessary. It is totally acceptable for member regions |
| // to be able to name placeholders from higher universes, as long as |
| // they don't actually do so. |
| is_proj(define::<'a>); |
| &() |
| } |
| |
| fn main() {} |
