{"ast_node_type":"variable","tokens":[{"end":66,"kind":"keyword","start":0,"text":"let"}]}
            let stack_len = self.bound_generic_params_stack.len();
        fn visit_poly_trait_ref(&mut self, trait_ref: &'a ast::PolyTraitRef) {
            self.bound_generic_params_stack.extend(trait_ref.bound_generic_params.iter().cloned());