From: Tom Lane <tgl@sss.pgh.pa.us>
To: ilmari@ilmari.org (Dagfinn Ilmari =?utf-8?Q?Manns=C3=A5ker?=)
cc: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>,
        Alvaro Herrera <alvherre@2ndquadrant.com>,
        Pavel Stehule <pavel.stehule@gmail.com>,
        Nikita Glukhov <n.gluhov@postgrespro.ru>,
        PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: Transform for pl/perl
In-reply-to: <2941.1529347229@sss.pgh.pa.us>
References: <20180606161453.tvp4ltavlcvejmmz@alvherre.pgsql>
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Comments: In-reply-to Tom Lane <tgl@sss.pgh.pa.us>
	message dated "Mon, 18 Jun 2018 14:40:29 -0400"
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Date: Mon, 18 Jun 2018 17:48:05 -0400
Message-ID: <29396.1529358485@sss.pgh.pa.us>
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I wrote:
> The remaining unresolved issue in this thread is Ilmari's suggestion
> that we should convert integers to Perl IV (or UV?) if they fit, rather
> than always convert to NV as now.

Oh ... after re-reading the thread I realized there was one other point
that we'd all forgotten about, namely the business about ~0 getting
converted to -1 rather than what Perl interprets it as.  Ilmari sent in
a patch for that, against which I'd raised two complaints:

1. Possible compiler complaints about a constant-false comparison,
on machines where type UV is 32 bits.

2. Need for secondary expected-output files, which'd be a pain to
maintain.

I realized that point 1 could be dealt with just by not trying to be
smart, but always using the convert-to-text code path.  Given that it
seems to be hard to produce a UV value in Perl, I doubt it is worth
working any harder than that.  Also, point 2 could be dealt with in
this perhaps crude way:

-- this might produce either 18446744073709551615 or 4294967295
SELECT testUVToJsonb() IN ('18446744073709551615'::jsonb, '4294967295'::js=
onb);

Pushed with those adjustments.

			regards, tom lane