On Wed, Apr 1, 2015 at 8:50 AM, Peter Eisentraut <peter_e@gmx.net> wrote:
On 3/31/15 1:05 AM, Michael Paquier wrote: > > > On Tue, Mar 31, 2015 at 9:40 AM, Peter Eisentraut <peter_e@gmx.net > <mailto:peter_e@gmx.net>> wrote: > > On 3/30/15 6:29 PM, Michael Paquier wrote: > > > > > > On Tue, Mar 31, 2015 at 5:39 AM, Peter Eisentraut <peter_e@gmx.net <mailto:peter_e@gmx.net> > > <mailto:peter_e@gmx.net <mailto:peter_e@gmx.net>>> wrote: > > > > On 3/25/15 1:32 AM, Michael Paquier wrote: > > > Well, I have no other cases than ones of the type mentioned upthread, > > > and honestly I am fine as long as we do not apply maths to a version > > > string. So attached is a patch that adds VERSION_NUM in > > > Makefile.global. > > > > How would you make use of this in an extension makefile? > > > > > > One use case is regression test list filtering depending on backend version. > > I'm interested in the exact syntax you'd use, to compare it to the > currently used techniques. > > > With the presence of VERSION_NUM directly in pg_config, the following > expression: > VERSION_NUM=$(shell $(PG_CONFIG) --version-num)
My question is, once you have this version number in a variable like VERSION_NUM, what specifically would you do with it?
For an extension that has a single branch compatible with a set of multiple major versions of Postgres, the cases are custom values for REGRESS_OPTS and REGRESS depending on the backend version. I also manipulate on a daily basis the same set of scripts across many platforms (on Windows as well using msysgit, and MSVC installation does not have pgxs stuff), so I would use it to simplify them. It is true that you can already do that by parsing the output of "pg_config --version", and that I would need to maintain both versions for some time (custom parsing of pg_config --version, and use of --version-num if this patch is accepted) but it looks IMO tempting to have directly the version number thinking long term if there is a simple integer number available at hand to identify a given version of PG.
