VKalVrtAthena::varHolder< T > Node1 VKalVrtAthena::varHolder< T > + m_var + varHolder() + ~varHolder() + get() + get_var() + get_typename() + clear() + branch_tree() Node2 VKalVrtAthena::BaseHolder + BaseHolder() + ~BaseHolder() + get_typename() + get_var() + clear() + branch_tree() Node2->Node1 Node3 std::string Node3->Node1 -m_typename Node4 std::basic_string< char > Node4->Node3