Re: Exposing PG_VERSION_NUM in pg_config

On Tue, Mar 24, 2015 at 07:26:18PM -0400, Tom Lane wrote:
> Andrew Gierth <andrew(at)tao11(dot)riddles(dot)org(dot)uk> writes:
> > "Tom" == Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> writes:
> > Tom> I concur with Michael that there's value in exposing the version
> > Tom> number in the numeric form used by PG_VERSION_NUM. However, I
> > Tom> also concur with Andrew that if the use-case for this is
> > Tom> Makefiles, pg_config is a pretty poor transmission mechanism. We
> > Tom> should instead add PG_VERSION_NUM to the version variables set in
> > Tom> Makefile.global.
>
> > I think there's an argument for both. pg_config already has a VERSION=
> > string in the output, and I think adding a VERSION_NUM= would be good
> > for consistency there. And people definitely do want to do version
> > comparisons in makefiles...
>
> Hm. We're all agreed that there's a use case for exposing PG_VERSION_NUM
> to the makefiles, but I did not hear one for adding it to pg_config; and
> doing the former takes about two lines whereas adding a pg_config option
> entails quite a lot of overhead (documentation, translatable help text,
> yadda yadda). So I'm not in favor of doing the latter without a much
> more solid case than has been made.

Would PG_VERSION_NUM in the Makefile actually help writers of
extensions to do numeric comparisons on the version of PostgreSQL in a
way that doesn't win a Rube Goldberg award?

If not, that's good and sufficient reason to make it a pg_config
output option.

Cheers,
David.
--
David Fetter <david(at)fetter(dot)org> http://fetter.org/
Phone: +1 415 235 3778 AIM: dfetter666 Yahoo!: dfetter
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