Date: Wed, 27 Feb 2019 18:41:37 -0300
From: Alvaro Herrera <alvherre@2ndquadrant.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Andres Freund <andres@anarazel.de>, pgsql-hackers@lists.postgresql.org
Subject: Re: POC: converting Lists into arrays
Message-ID: <20190227214137.GA20958@alvherre.pgsql>
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On 2019-Feb-27, Tom Lane wrote:

> I'm particularly unsure about whether we need two macros; though the
> way I initially tried it with just list_cell_is_last() seemed kind of
> double-negatively confusing in the places where the test needs to be
> not-last.  Also, are these macro names too long, and if so what would
> be better?

I think "!list_cell_is_last()" is just as readable, if not more, than
the "is_not_last" locution:

		appendStringInfoChar(&buf, '\'');
		if (!list_cell_is_last(l))
			appendStringInfoString(&buf, ", ");

I'd go with a single macro.


+1 for backpatching the new macros, too.  I suspect extension authors
are going to need to provide compatibility versions anyway, to be
compilable against older minors.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services