{"ast_node_type":"other","tokens":[{"end":71,"kind":"keyword","start":0,"text":"ImplTraitContext::Existential"}]}
                    ImplTraitContext::Existential => DefKind::OpaqueTy,
                    ImplTraitContext::Universal => DefKind::TyParam,
                    ImplTraitContext::InBinding => return visit::walk_ty(self, ty),