From: Tom Lane <tgl@sss.pgh.pa.us>
To: Stephen Frost <sfrost@snowman.net>
cc: Pavel Stehule <pavel.stehule@gmail.com>,
        Christoph Berg <christoph.berg@credativ.de>,
        Daniel Verite <daniel@manitou-mail.org>,
        PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Subject: Re: One-shot expanded output in psql using \G
In-reply-to: <20170130153532.GE9812@tamriel.snowman.net>
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Comments: In-reply-to Stephen Frost <sfrost@snowman.net>
	message dated "Mon, 30 Jan 2017 10:35:33 -0500"
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Date: Mon, 30 Jan 2017 10:49:17 -0500
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Stephen Frost <sfrost@snowman.net> writes:
> * Tom Lane (tgl@sss.pgh.pa.us) wrote:
>> Why not?  To me it reads as "\g with an x option".  The "x" refers to
>> the implied "\x", so it's not an arbitrary choice at all.

> That's not how '\dx' works, as I pointed out, so I don't see having the
> second character being 'x' to imply "\x mode" makes sense.

It is how \d[tisv] works, or the S or + modifiers to \d.  If you don't
like the "x" in particular, feel free to propose a different letter that
makes more sense to you --- but I'm pretty convinced that this ought to
be seen as \g-plus-a-modifier.

>> The main problem I see with \G is that it's a dead end.  If somebody
>> comes along next year and says "I'd like a variant of \g with some other
>> frammish", what will we do?  There are no more case variants to use.

> I don't believe there's any reason to think someone else couldn't come
> along later and add \gq for whatever they want.  Simply because we use
> \G for something doesn't mean \g can't ever be further extended.

So at some point we'd be documenting \G as a legacy mysql-compatible
spelling of \gx, because it would become blindingly obvious that it was
a non-orthogonal wart.  Let's just skip that phase and get to the
extensible syntax.

			regards, tom lane


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