{"ast_node_type":"other","tokens":[{"end":92,"kind":"keyword","start":0,"text":"//"}]}
                // and opaque types: If the `self_ty` is `Sized`, then the metadata is `()`.
                // This is the "fallback impl" for type parameters, unnormalizable projections
                // FIXME(ptr_metadata): This impl overlaps with the other impls and shouldn't