SAP OO OBS SY REPID 1

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Passing sy-repid Not Allowed
In ABAP Objects, you cannot pass the system field sy-repid as an actual parameter to an external procedure.

In ABAP Objects, the following statement causes an error message:

CALL FUNCTION func EXPORTING p = sy-repid.

Correct syntax:

DATA repname TYPE sy-repid.

repname = sy-repid.
CALL FUNCTION func EXPORTING p = repname.

Reason:

When the parameters are passed to the formal parameters, sy-repid already contains the name of the main program of the procedure you have called, even though you intended to pass the name of the calling program.