Re: Why do we have perl and sed versions of Gen_dummy_probes?

On 5/10/21 12:07 PM, Tom Lane wrote:
> Andrew Dunstan <andrew(at)dunslane(dot)net> writes:
>> On 5/10/21 7:16 AM, Dagfinn Ilmari Mannsåker wrote:
>>> Peter Eisentraut <peter(dot)eisentraut(at)enterprisedb(dot)com> writes:
>>>> This recipe doesn't produce a Gen_dummy_probes.pl that matches exactly
>>>> the one that is there now. If this is going to be the preferred method,
>>>> then we should generate it once so that it matches going forward.
>>> Which version of perltidy do you have installed? For me it generates
>>> identical versions using any of 20170521 (per src/tools/pgindent/README),
>>> 20201207 (what I happened to have installed before), and 20210402 (the
>>> latest).
>> Yep:
> For me, using App-s2p-1.003 and perltidy v20170521, it works
> as long as I start with the previous version of
> Gen_dummy_probes.pl in place. I first tried to test this by
> "rm Gen_dummy_probes.pl; make Gen_dummy_probes.pl", and what
> I got was a script without all the initial commentary nor
> the first line of actual Perl code.
>
> I don't think this is good practice; it implies that any
> accidental corruption of the commentary would be carried
> forward. I think we should be extracting the commentary
> from Gen_dummy_probes.sed.
>
>

I don't know how likely accidental corruption is, but OK, let's not make
the next generation dependent on the current generation of the file. The
simplest way around that seems to me to cache the perl prolog, as in the
attached patch Is that more to your liking? I also adjusted it so we
pick up the first line of code from s2p rather than from the prolog,
which is now just comments and the #! line.

cheers

andrew

--
Andrew Dunstan
EDB: https://www.enterprisedb.com