From: Tom Lane <tgl@sss.pgh.pa.us>
To: Robert Haas <robertmhaas@gmail.com>
cc: Dilip Kumar <dilipbalaut@gmail.com>, Justin Pryzby <pryzby@telsasoft.com>,
        Andres Freund <andres@anarazel.de>,
        Tomas Vondra <tomas.vondra@2ndquadrant.com>,
        David Steele <david@pgmasters.net>,
        Ildus Kurbangaliev <i.kurbangaliev@gmail.com>,
        Dmitry Dolgov <9erthalion6@gmail.com>,
        Andrey Borodin <x4mmm@yandex-team.ru>,
        PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: [HACKERS] Custom compression methods (mac+lz4.h)
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Comments: In-reply-to Robert Haas <robertmhaas@gmail.com>
	message dated "Mon, 22 Mar 2021 11:59:18 -0400"
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Date: Mon, 22 Mar 2021 12:04:58 -0400
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Robert Haas <robertmhaas@gmail.com> writes:
> On Mon, Mar 22, 2021 at 11:48 AM Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> Possibly the former names should survive and the latter become
>> wrappers around them, not sure.  But we shouldn't be using the "4B"
>> terminology anyplace except this part of postgres.h.

> I would argue that it shouldn't be used any place at all, and that we
> ought to go the other direction and get rid of the existing macros -
> e.g. change #define VARATT_IS_1B_E to #define VARATT_IS_EXTERNAL
> instead of defining the latter as a no-value-added wrapper around the
> former. Maybe at one time somebody thought that the test for
> VARATT_IS_EXTERNAL might someday have more cases than just
> VARATT_IS_1B_E, but that's not looking like a good bet in 2021.

Maybe.  I think the original idea was exactly what the comment says,
to have a layer of macros that'd deal with endianness issues and no more.
That still seems like a reasonable plan to me, though perhaps it wasn't
executed very well.

			regards, tom lane