boost::make_recursive_variant< flexible_type, std::shared_ptr< unity_sgraph_base >, dataframe_t, std::shared_ptr< model_base >, std::shared_ptr< unity_sframe_base >, std::shared_ptr< unity_sarray_base >, std::map< std::string, boost::recursive_variant_ >, std::vector< boost::recursive_variant_ >, boost::recursive_wrapper< function_closure_info > >::type variant_type