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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andrew Dunstan <andrew.dunstan@2ndquadrant.com>
cc: Alexander Korotkov <a.korotkov@postgrespro.ru>,
        Nikita Glukhov <n.gluhov@postgrespro.ru>,
        Robert Haas <robertmhaas@gmail.com>,
        Oleg Bartunov <obartunov@gmail.com>,
        Pavel Stehule <pavel.stehule@gmail.com>,
        PostgreSQL-development <pgsql-hackers@postgresql.org>
Subject: Re: jsonpath
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Comments: In-reply-to Andrew Dunstan <andrew.dunstan@2ndquadrant.com>
	message dated "Tue, 20 Mar 2018 15:36:39 +1030"
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Andrew Dunstan <andrew.dunstan@2ndquadrant.com> writes:
>> That seems like a quite limited list of functions.  What about
>> reworking them providing a way of calling them without risk of
>> exception?

> I haven't seen a response to this email. Do we need one before
> proceeding any further with jsonpath?

I've not been following this thread in detail, but IMO any code anywhere
that thinks that no error can be thrown out of non-straight-line code is
broken beyond redemption.  What, for example, happens if we get ENOMEM
within one of the elog.c functions?

I did look through 0007-jsonpath-arithmetic-error-handling-v12.patch,
and I can't believe that's seriously proposed for commit.  It's making
some pretty fragile changes in error handling, and so far as I can
find there is not even one line of commentary as to what the new
design rules are supposed to be.  Even if it's completely bug-free
today (which I would bet against), how could we keep it so?

			regards, tom lane