FINAL new ABAP keyword - guidance

[prokopp80]

Hi colleagues,
recently the new FINAL keyword has been introduced. Do you plan to document a common guidance for it?
In my opinion this was something that I missed in ABAP for long time.

Thank you,
Br. Petr

[ruthiel]

Hello @prokopp80 ,

Can you explain what new keyword FINAL are you referring?

Is it the FINAL for classes and methods? If yes, it exists for a long time yet.

Regards,
Ruthiel

[fabianlupa]

This is referring to the new FINAL keyword for immutable inline declarations. It is available in the BTP Trial with SAP_BASIS 789. The online documentation does not include it yet. Should show up as a third item here: https://help.sap.com/doc/abapdocu_cp_index_htm/CLOUD/en-US/index.htm?file=abeninline_declarations.htm

https://blogs.sap.com/2022/07/04/reverse-loop-finally-possible-with-step-addition-for-abap-internal-tables/comment-page-1/#comment-630060

[jordao76]

Interesting, like const vs let in JavaScript.

I'd say then, that FINAL should be preferred to declare variables that are not reassigned.

[ruthiel]

This is referring to the new FINAL keyword for immutable inline declarations. It is available in the BTP Trial with SAP_BASIS 789. The online documentation does not include it yet. Should show up as a third item here: https://help.sap.com/doc/abapdocu_cp_index_htm/CLOUD/en-US/index.htm?file=abeninline_declarations.htm

https://blogs.sap.com/2022/07/04/reverse-loop-finally-possible-with-step-addition-for-abap-internal-tables/comment-page-1/#comment-630060

Thank you @fabianlupa for this explanation.
First time hearing about that.

It seems like a constant but inside a specific context.

[nomssi]

FINAL in ABAP means the variable value can be changed only at the single write position.
But it can be changed more than once, e.g. in a LOOP.

https://blogs.sap.com/2022/10/25/finally-a-declaration-of-immutable-variables-with-final-in-abap/

The recommendation should probably be: prefer FINAL to DATA whenever possible.

[ConjuringCoffee]

I have closed the pull request I made to fix this issue for now. As Björn explained in his comment, the FINAL keyword has more subtleties to it than I expected and needs a better description.