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//@ revisions: old next
//@[next] compile-flags: -Znext-solver
//@ ignore-compare-mode-next-solver (explicit revisions)
//@ check-pass
// Generalizing an alias referencing escaping bound variables
// is hard. We previously didn't replace this alias with inference
// variables but did replace nested alias which do not reference
// any bound variables. This caused us to stall with the following
// goal, which cannot make any progress:
//
// <<T as Id>::Refl as HigherRanked>::Output<'a>
// alias-relate
// <?unconstrained as HigherRanked>::Output<'a>
//
//
// cc trait-system-refactor-initiative#110
#![allow(unused)]
trait HigherRanked {
type Output<'a>;
}
trait Id {
type Refl: HigherRanked;
}
fn foo<T: Id>() -> for<'a> fn(<<T as Id>::Refl as HigherRanked>::Output<'a>) {
todo!()
}
fn bar<T: Id>() {
// we generalize here
let x = foo::<T>();
}
fn main() {}
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