InDet::ModuleKeyHelper< T, T_ROW_BITS, T_COL_BITS, T_CHIP_BITS, T_MASK_SEL_BITS, T_N_MASKS >::Empty Node1 InDet::ModuleKeyHelper < T, T_ROW_BITS, T_COL _BITS, T_CHIP_BITS, T_MASK _SEL_BITS, T_N_MASKS >::Empty