[ABAP OO] Generic method get lines

Hi Experts,

I am creating a generic method to get the numbers of lines from any table, like below:

TABNAME type string.

LINES type i.

METHOD get_lines_from_any_dbtab.

  DATA lo_tab TYPE REF TO data  .

  CREATE DATA  lo_tab  TYPE TABLE OF (tabname) .
  SELECT *  FROM (tabname)  INTO TABLE lo_tab .

  DESCRIBE TABLE lo_tab LINES lines  .
  CONDENSE lines 

METHOD.

I have an error message during the compilation as:

LO_TAB is not an internal table.

Any idea ?

Kind regards.

Rachid.