columnar::VariantContainerId< CIBase, CIList > Node1 columnar::VariantContainer Id< CIBase, CIList > + isContainerId + isMutable + perEventRange + perEventId + numVariants + isValidContainer() + getVariantIndex() Node2 std::array< std::string _view, numVariants > Node2->Node1 +idNameArray Node3 std::string_view Node3->Node2 +elements Node4 std::basic_string_view < char > Node4->Node3