{"ast_node_type":"variable","tokens":[{"end":81,"kind":"keyword","start":0,"text":"let"}]}
                        let default = self.tcx.const_param_default(param.def_id);
                    if let ty::GenericParamDefKind::Const { has_default: true, .. } = param.kind {
                        record!(self.tables.const_param_default[param.def_id] <- default);