topic Re: difference between funtion module and pre define function in abap in Application Development and Automation Discussions

difference between funtion module and pre define function in abap

Former Member — Sun, 23 Oct 2005 06:26:27 GMT

HI,

CAN ANY ONE TELL ME WHAT IS DIFFERENCT BETWEEN FUNCTION MODULE AND

PREDEFINE FUNCITON IN ABAP.

IN ORDER TO EXPLAIN U MY QUESTION I WILL GIVE U AN EXAMPLE OF COUNTING

THE NUMBER OF CHARACTERS IN A STRING

THE FUNCITON MODULE FOR THIS OPERATION IS

CALL FUNCTION 'STRING_LENGTH'

EXPORTING

STRING =

IMPORTING

LENGTH =

AND THE PREDEFINE FUNCTION FOR THIS OPERATON IS

STR_LEN = STRLEN( STRING ).

I WANT TO KNOW WHAT IS DIFFERNECE BETWEEN ABOUT TWO FUNCTIONS

note: the fm itself is using that predefine function and it is allowing us to use the predefine funtion also.

regards,

MAQSOOD

Re: difference between funtion module and pre define function in abap

Former Member — Sun, 23 Oct 2005 06:43:39 GMT

Function Modules mostly will have upward capability . So suppose the syntax of STRLEN changes , the function module 'STRING_LENGTH' will have the updated version .

On WAS 620 the FM STRING_LENGTH conatins code -

<b>class cl_abap_list_utilities definition load.

length = cl_abap_list_utilities=>dynamic_output_length( string ).</b>

May be you are on a lower release ( 46B / 46C ) so you still see STRLEN in the Function module .

So STRLEN is a key word of ABAP whose syntax may change with upgrade . But the FM STRING_LENGTH would keep the functionality even on upgrades . So its better to use standard FMs if available for any functinality.

Cheers.

Re: difference between funtion module and pre define function in abap

krzysztof_konitz4 — Sun, 23 Oct 2005 08:46:27 GMT

Hi,

I think different than Sanjay. I consider that it's safer to use one of ABAP standard syntax command than one of SAP function module. Syntax command can be in future marked as obsolete but should work also in future releases.

There is no such warranty for SAP FM. Unless it's BAPI.

Krzys

Re: difference between funtion module and pre define function in abap

Former Member — Sun, 23 Oct 2005 09:00:47 GMT

I suggest use ABAP command, which is a part of ABAP Language. For Function Modules, you need check if it released, In many cases, they are not leased, which means it is not available for customer use.