Re: PL/pgSQL 'i = i + 1' Syntax

Albe Laurenz said:
> Tom Lane wrote:
>>> It ought to be illegal to modify the loop control variable anyway,
>>> IMNSHO - it certainly is in Ada, the distant antecedent of pl/pgsql.
>>
>> If modifying the loop variable is disallowed in PL/SQL, I'm all for
>> disallowing it in plpgsql, otherwise not.  Anyone have a
>> recent copy of Oracle to try it on?
>
> I tried this on Oracle 10.2.0.2.0 (which is the most recent version):
>
> SET SERVEROUTPUT ON
> BEGIN
>   FOR i IN 1..10 LOOP
>      i := i + 1;
>      DBMS_OUTPUT.PUT_LINE(i);
>   END LOOP;
> END;
> /
>      i := i + 1;
>      *
> ERROR at line 3:
> ORA-06550: line 3, column 7:
> PLS-00363: expression 'I' cannot be used as an assignment target
> ORA-06550: line 3, column 7:
> PL/SQL: Statement ignored
>
> And the documentation also explicitly states that it is not allowed.
>

So should we if it can be done conveniently. That might be a big IF - IIRC
many Pascal compilers ignore the similar language rule because implementing
it is a pain in the neck.


> By the way, PL/SQL screams if you want to do an assignment with '='.
> But I guess that the current behaviour of PL/pgSQL should not reflect
> that to maintain backward compatibility, right?
>

I think it should. The current behaviour is undocumented and more than icky.

cheers

andrew