Subject: Re: \if, \elseif, \else, \endif (was Re: PSQL commands:
 \quit_if, \quit_unless)
To: Corey Huinker <corey.huinker@gmail.com>
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CC: Fabien COELHO <coelho@cri.ensmp.fr>, Erik Rijkers <er@xs4all.nl>, Tom Lane
	<tgl@sss.pgh.pa.us>, Daniel Verite <daniel@manitou-mail.org>, PostgreSQL
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From: Jim Nasby <Jim.Nasby@BlueTreble.com>
Message-ID: <ce7ac5bd-9b62-80e2-283d-973b0b72ed56@BlueTreble.com>
Date: Fri, 3 Feb 2017 18:42:18 -0600
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On 2/2/17 4:39 PM, Corey Huinker wrote:
>
> On Wed, Feb 1, 2017 at 4:58 PM, Jim Nasby <Jim.Nasby@bluetreble.com
> <mailto:Jim.Nasby@bluetreble.com>> wrote:
>
>     I think the issue here is that the original case for this is a user
>     accidentally getting into an \if and then having no clue what's
>     going on. That's similar to what happens when you miss a quote or a
>     semicolon. We handle those cases with %R, and I think %R needs to
>     support if as well.
>
>     Perhaps there's value to providing more info (active branch, etc),
>     but ISTM trying to do that will just confuse the original (%R) case.
>
>
> Jim,
>
> After spending a few minutes to familiarize myself with %R, I'm in
> agreement with your second statement (adding if-else to %R will just
> confuse %R). However, your first statement seems to indicate the
> opposite. Can you elaborate?

My point was that we need a way for users to know if they're stuck in an 
\if block, and right now that's handled with %R (inside transaction, 
parens, etc). My other point is that adding all the extra info to %R 
would be folly.

Since the current consensus is to be very verbose about \if, this is 
obviously a non-issue. Maybe worth adding a 'I' case to %R, but no big 
deal if that doesn't happen.
-- 
Jim Nasby, Data Architect, Blue Treble Consulting, Austin TX
Experts in Analytics, Data Architecture and PostgreSQL
Data in Trouble? Get it in Treble! http://BlueTreble.com
855-TREBLE2 (855-873-2532)


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