Re: [HACKERS] [COMMITTERS] pgsql: Add psql variables showing server version and psql version.

Fabien COELHO <coelho@cri.ensmp.fr> writes:
> Thus short, simple but meaningful examples which show how to do something 
> useful with all that in the documentation may help people take advantage 
> of these new features.

I don't have an objection to providing an example.  I wasn't terribly
impressed with Simon's version, but maybe we can do better.  I think
it should be concrete, not partly abstract; and likely it needs to be
with \if not the variable proper.

> Given my experience with "\d*", I'm not sure I would assume that a new 
> psql feature would work with older servers.

I don't recall anyone questioning whether PQserverVersion() would work
with older servers.  Being able to tell what version the server is is
sort of the point, no?  If there were a restriction on what it would
work with, I would agree that that needs to be documented.  But I
don't think "yes, it really works" is a helpful use of documentation
space.
        regards, tom lane