runtime error

Hello All,

DATA: regex TYPE REF TO cl_abap_regex,
      moff TYPE i,
      mlen TYPE i,
      text  TYPE        string.


CREATE OBJECT regex
  EXPORTING
    pattern      = 'f'
    simple_regex = 'X'.

cause an runtime error if no input field is populated.

Some times it is possible to keep the fields empty.

But anyway the programm should not dump.

How can I prevent that ?

Regards

sas