InDetPVNNSelection::internal::VertexVarGetterNoDefault< T > Node1 InDetPVNNSelection ::internal::VertexVarGetter NoDefault< T > - m_getter + VertexVarGetterNoDefault() + operator()() Node2 std::string     Node2->Node1 -m_name Node3 std::basic_string< Char >     Node3->Node2