}
  strings::StrAppend(&class_decl, "  ",
                     GetConstructorDecl(op_info, "", /* include_attr */ false),
                     ";\n");
  if (op_info.has_optional_attrs) {
    strings::StrAppend(&class_decl, "  ",
                       GetConstructorDecl(op_info, "", /* include_attr */ true),
                       ";\n");
  }
  if (op_info.output_types.empty()) {

  OpInfo(const OpDef& graph_op_def, const ApiDef& api_def,
         const std::vector<string>& aliases);
  OpInfo(const OpDef& graph_op_def, const ApiDef& api_def);
  string GetOpAttrStruct() const;
  string GetConstructorDecl(StringPiece op_name_prefix,
                            bool include_attr) const;

  string op_name;
  std::vector<string> arg_types;
  std::vector<string> arg_names;
  std::vector<string> output_types;