  void readStructEnd() {
    if (!nestedStructFieldIds_.empty()) {
      lastFieldId_ = nestedStructFieldIds_.back();
      nestedStructFieldIds_.pop_back();
    }
  }
  void readStructEnd() {
    if (!nestedStructFieldIds_.empty()) {
      lastFieldId_ = nestedStructFieldIds_.back();
      nestedStructFieldIds_.pop_back();
    }
  }