// The "projection gap" is particularly "fun" around higher-ranked // projections. This is because the current code is hard-coded to say // that a projection that contains escaping regions, like `>::Foo` where `'z` is bound, can only be found to // outlive a region if all components that appear free (`'y`, where) // outlive that region. However, we DON'T add those components to the // implied bounds set, but rather we treat projections with escaping // regions as opaque entities, just like projections without escaping // regions. trait Trait1 { } trait Trait2<'a, 'b> { type Foo; } // As a side-effect of the conservative process above, the type of // this argument `t` is not automatically considered well-formed, // since for it to be WF, we would need to know that `'y: 'x`, but we // do not infer that. fn callee<'x, 'y, T>(t: &'x dyn for<'z> Trait1< >::Foo >) //~^ ERROR the trait bound `for<'z> T: Trait2<'y, 'z>` is not satisfied //~| ERROR the trait bound `for<'z> T: Trait2<'y, 'z>` is not satisfied { } fn main() { }