{"ast_node_type":"other","tokens":[{"end":90,"kind":"keyword","start":0,"text":"self.tcx.fn_sig(def_id).instantiate_identity().skip_binder().inputs();"}]}
                    self.tcx.fn_sig(def_id).instantiate_identity().skip_binder().inputs();
                let arg_defs =
                for (arg_num, arg_def) in arg_defs.iter().enumerate() {