Re: better support of out parameters in plperl

I wrote:
> Pavel Stehule wrote:
>> Hello,
>>
>> I send two small patches. First does conversion from perl to
>> postgresql array in OUT parameters. Second patch allow hash form
>> output from procedures with one OUT argument.
>>
>
> I will try to review these in the next 2 weeks unless someone beats me
> to it.
>
>

I have reviewed this lightly, as committed by Bruce, and have some
concerns. Unfortunately, the deathof my main workstation has cost me
much of the time I intended to use for a more thorough review, so there
may well be more issues than are outlined here.

First, it is completely undocumented.

Second, this comment is at best confusing:

  /* if value is ref on array do to pg string array conversion */


Third, it appears to assume that we will have names for all OUT params. But names are optional, as I understand it.
Arguably,we should be treating the returns positionally, and thus return an arrayref when there are OYT params, not a
hashref,and ignore the names - after all, all perl function args are nameless, in fact, even if you use a naming
conventionto refer to them. 

Fourth, I don't understand the change: "allow hash form output from procedures with one OUT argument." That seems very
non-orthogonal,and I can't see any good reason for it. 

Lastly, if you look at the expected output as committed,it appears to have been prepared without being actually
examined,for example: 


CREATE OR REPLACE FUNCTION test05(OUT a varchar) AS $$
         return {a=>'ahoj'};
       $$ LANGUAGE plperl;
SELECT '05' AS i,a FROM test05();
  i  |        a
 ----+-----------------
  05 | HASH(0x8558f9c)
 (1 row)


what???

And now that I look I see every buildfarm box broken on PLCheck. That's no surprise at all.


The conversation regarding these features appears only to have started on July 28th, which was probably much too late
givensome of the issues. Unless we can solve these issues very fast I would be inclined to say this should be tabled
for8.3. I think this is a fairly good illustration of the danger of springing a feature, largely undiscussed, on the
communityjust about freeze time. 

cheers

andrew