Received: from malur.postgresql.org ([217.196.149.56])
	by arkaria.postgresql.org with esmtps
 (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256)
	(Exim 4.92)
	(envelope-from <pgsql-hackers-owner+archive@lists.postgresql.org>)
	id 1paKDa-00035m-6c
	for pgsql-hackers@arkaria.postgresql.org; Thu, 09 Mar 2023 17:38:18 +0000
Received: from localhost ([127.0.0.1] helo=malur.postgresql.org)
	by malur.postgresql.org with esmtp (Exim 4.92)
	(envelope-from <pgsql-hackers-owner+archive@lists.postgresql.org>)
	id 1paKDY-0000Lr-VD
	for pgsql-hackers@arkaria.postgresql.org; Thu, 09 Mar 2023 17:38:16 +0000
Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29])
	by malur.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256)
	(Exim 4.92)
	(envelope-from <tgl@sss.pgh.pa.us>)
	id 1paKDY-0000Lc-Lm
	for pgsql-hackers@lists.postgresql.org; Thu, 09 Mar 2023 17:38:16 +0000
Received: from sss.pgh.pa.us ([66.207.139.130])
	by magus.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256)
	(Exim 4.92)
	(envelope-from <tgl@sss.pgh.pa.us>)
	id 1paKDW-0004uj-0T
	for pgsql-hackers@lists.postgresql.org; Thu, 09 Mar 2023 17:38:16 +0000
Received: from sss1.sss.pgh.pa.us (localhost [127.0.0.1])
	by sss.pgh.pa.us (8.15.2/8.15.2) with ESMTP id 329Hc7UW429188;
	Thu, 9 Mar 2023 12:38:08 -0500
From: Tom Lane <tgl@sss.pgh.pa.us>
To: Jim Jones <jim.jones@uni-muenster.de>
cc: Peter Eisentraut <peter.eisentraut@enterprisedb.com>,
        Peter Smith <smithpb2250@gmail.com>,
        Nikolay Samokhvalov <samokhvalov@gmail.com>,
        PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>,
        Andrey Borodin <amborodin86@gmail.com>
Subject: Re: [PATCH] Add pretty-printed XML output option
In-reply-to: <1cbe1087-6acb-2b0a-dc9b-0a2d5b99e466@uni-muenster.de>
References: <2f5df461-dad8-6d7d-4568-08e10608a69b@uni-muenster.de>
 <62643598-b80d-90f4-8901-b85dccadf4c4@enterprisedb.com>
 <CANNMO+Kwb4_87G8qDeN+Vk1B1vX3HvgoGW+13fJ-b6rj7qbAww@mail.gmail.com>
 <beb5a47d-4684-4b2f-8647-bacb6bd60acf@uni-muenster.de>
 <CANNMO+L5X2ynyXL2RK7gTVA-pj=Z8o8FCCr6RwLfRK_LinjSbg@mail.gmail.com>
 <d79950fd-b3f5-783c-919a-a95de23c0c2c@enterprisedb.com>
 <4c2efca5-8257-2424-6687-07c65e319e95@uni-muenster.de>
 <CAHut+PtMHeBBZ2zv0Bk7-4KMkSrrxZ9PZxUCzhpwTGVk+8G3cw@mail.gmail.com>
 <2eac4d78-2b20-e8ec-54cc-22a88653a1cc@uni-muenster.de>
 <CAHut+PsgXxbzzsG+VqHUa4Kz3G4B-anNmF3-GENwuUdfMJtowA@mail.gmail.com>
 <fb2a543b-e615-d9ba-8402-909631f9b212@uni-muenster.de>
 <CAHut+Pvryt_+wA7TwKVaaF0e6Pm5LaPZQLKatp=78oFd8vMh3A@mail.gmail.com>
 <6cb296fe-4b49-3691-633e-2e2366997b04@uni-muenster.de>
 <3baf8f25-3bd7-7db5-0b31-e4c92b6269ba@enterprisedb.com>
 <1cbe1087-6acb-2b0a-dc9b-0a2d5b99e466@uni-muenster.de>
Comments: In-reply-to Jim Jones <jim.jones@uni-muenster.de>
	message dated "Thu, 23 Feb 2023 09:20:00 +0100"
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-ID: <429186.1678383487.1@sss.pgh.pa.us>
Date: Thu, 09 Mar 2023 12:38:07 -0500
Message-ID: <429187.1678383487@sss.pgh.pa.us>
List-Id: <pgsql-hackers.lists.postgresql.org>
List-Help: <https://lists.postgresql.org/manage/>
List-Subscribe: <https://lists.postgresql.org/manage/>
List-Post: <mailto:pgsql-hackers@lists.postgresql.org>
List-Owner: <mailto:pgsql-hackers-owner@lists.postgresql.org>
List-Archive: <https://www.postgresql.org/list/pgsql-hackers>
Archived-At: 
 <https://www.postgresql.org/message-id/429187.1678383487%40sss.pgh.pa.us>
Precedence: bulk

While reviewing this patch, I started to wonder why we don't eliminate
the maintenance hassle of xml_1.out by putting in a short-circuit
at the top of the test, similar to those in some other scripts:

/* skip test if XML support not compiled in */
SELECT '<value>one</value>'::xml;
\if :ERROR
\quit
\endif

(and I guess xmlmap.sql could get the same treatment).

The only argument I can think of against it is that the current
approach ensures we produce a clean error (and not, say, a crash)
for all xml.c entry points not just xml_in.  I'm not sure how much
that's worth though.  The compiler/linker would tell us if we miss
compiling out every reference to libxml2.

Thoughts?

			regards, tom lane