{"ast_node_type":"other","tokens":[{"end":136,"kind":"keyword","start":0,"text":"desc"}]}
        desc { |tcx| "finding the slot within vtable for trait object `{}` vtable ptr during trait upcasting coercion from `{}` vtable",
    query supertrait_vtable_slot(key: (Ty<'tcx>, Ty<'tcx>)) -> Option<usize> {
            key.1, key.0 }