topic Re: Dynamic programming using FOR Expressions in Application Development and Automation Discussions

Dynamic programming using FOR Expressions

Former Member — Fri, 24 Aug 2018 09:56:20 GMT

Hello Team,

I read somewhere all LOOP statement can be tweaked to form FOR statement. But I wasn't able to achieve it.

I am trying to achieve a dynamic looping using FOR statement. Is FOR supports such a requirement by somehow?

In my case, iteration is dependent on certain values. So can I have such a flexibility using FOR statement. These values are not possible to pass in WHERE conditions.

"<lt_change_log> is dynamic internal table
LOOP AT <lt_change_log> ASSIGNING FIELD-SYMBOL(<ls_change_log>).
ASSIGN COMPONENT 'CDHDR' OF STRUCTURE <ls_change_log> TO <ls_cdhdr>.
LOOP AT <ls_change_log>-cdpos_tab[] ASSIGNING FIELD-SYMBOL(<ls_cdpos>)WHERE changenr = <ls_cdhdr>-changenr.
 if <ls_cdpos>-new_value is not initial.
  ....
 else.
  continue.
 endif.
ENDLOOP.
ENDLOOP.

Re: Dynamic programming using FOR Expressions

retired_member — Fri, 24 Aug 2018 15:07:42 GMT

"Is FOR supports such a requirement by somehow?"

See the documentation,

https://help.sap.com/doc/abapdocu_752_index_htm/7.52/en-US/index.htm?file=abenfor_cond.htm

Dynamic WHERE is possible and also nested FORs should work.

What you can't do, is to nest statements as ASSIGN COMPONENT. Only other expressions are possible. And for that you still need LOOP. But that's OK, since expressions don't make statements obsolete. They have another scope.

Re: Dynamic programming using FOR Expressions

Former Member — Mon, 27 Aug 2018 05:22:56 GMT

Hi Horst,

OK thank you for the information. So for now I would understand that, FOR cannot support dynamic programming.. So LOOP ENDLOOP is still essential..

Re: Dynamic programming using FOR Expressions

pokrakam — Mon, 27 Aug 2018 06:40:24 GMT

Why? What's the point of replacing LOOP? Where did you read this?

Re: Dynamic programming using FOR Expressions

retired_member — Mon, 27 Aug 2018 07:37:12 GMT

Edit: I enhanced the answer.