From Martin Maechler <maechler@stat.math.ethz.ch>  Fri Sep 15 13:31:48 2000
From: Martin Maechler <maechler@stat.math.ethz.ch> (Martin Maechler)
Date: Fri, 15 Sep 2000 14:31:48 +0200
Subject: [Rd] NULL == NULL
Message-ID: <14786.5812.611071.633622@gargle.gargle.HOWL>

gives an error in R.

In both S+3 and S+5, it "works" by returning NULL or logical(0),
respectively.

As a consequence,

   all(x == y)

returns TRUE in Splus, when x <- y <- NULL
but gives an error in R.

Do we have a good reason *not* to return  logical(0) ?

Martin Maechler <maechler@stat.math.ethz.ch>	http://stat.ethz.ch/~maechler/
Seminar fuer Statistik, ETH-Zentrum  LEO D10	Leonhardstr. 27
ETH (Federal Inst. Technology)	8092 Zurich	SWITZERLAND
phone: x-41-1-632-3408		fax: ...-1228			<><
-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
r-devel mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html
Send "info", "help", or "[un]subscribe"
(in the "body", not the subject !)  To: r-devel-request@stat.math.ethz.ch
_._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._


[Rd] NULL == NULL
Martin Maechler