From: Tom Lane <tgl@sss.pgh.pa.us>
To: Alexander Korotkov <aekorotkov@gmail.com>
cc: Robert Haas <robertmhaas@gmail.com>,
        "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Subject: Re: post-freeze damage control
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Comments: In-reply-to Alexander Korotkov <aekorotkov@gmail.com>
	message dated "Tue, 09 Apr 2024 23:48:12 +0300"
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Date: Tue, 09 Apr 2024 17:05:02 -0400
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Alexander Korotkov <aekorotkov@gmail.com> writes:
> On Tue, Apr 9, 2024 at 11:37 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> What exactly is the point of having a NodeTag in the struct though?
>> If you don't need it to be a valid Node, that seems pointless and
>> confusing.  We certainly have plenty of other lists that contain
>> plain structs without tags, so I don't buy that the List
>> infrastructure is making you do that.

> This code mixes Expr's and hash entries in the single list.  The point
> of having a NodeTag in the struct is the ability to distinguish them
> later.

If you're doing that, it really really ought to be a proper Node.
If nothing else, that would aid debugging by allowing the list
to be pprint'ed.

			regards, tom lane