From Martin Maechler <maechler@stat.math.ethz.ch>  Fri Jan 18 17:13:07 2002
From: Martin Maechler <maechler@stat.math.ethz.ch> (Martin Maechler)
Date: Fri, 18 Jan 2002 18:13:07 +0100
Subject: [Rd] Should dots be used in generic functions?
In-Reply-To: <3C484645.C75F29FB@research.bell-labs.com>
References: <5q7g4ukk1e73c3tabs3cethicncefap72k@4ax.com>
 <3C48362F.2856D89@research.bell-labs.com>
 <3C4843DE.58B734DD@bank-banque-canada.ca>
 <3C484645.C75F29FB@research.bell-labs.com>
Message-ID: <15432.22435.773412.10170@gargle.gargle.HOWL>

>>>>> "John" == John Chambers <jmc@research.bell-labs.com> writes:

    John> Paul Gilbert wrote:
    >> 
    >> John Chambers wrote:
    >> 
    >> > 2- the method can have arguments not in the generic if the generic has
    >> > ..., with the interpretation that the actual arguments matching ... may
    >> > correspond to the extra arguments.
    >> 
    >> In this case, would the method have ... as well, or not?

    John> Subject to discussion .... Either seems plausible.  What currently
    John> happens is that setMethod constructs a method that contains the
    John> programmer's supplied definition as a local function and calls it
    John> (needed so that argument re-matching can take place).

    John> An advantage of the method not having ... is that errors in naming
    John> arguments are more likely to be caught.

Indee.  Leading to much better / understandable error messages in
	  many cases; (etc... you know my stories on this subject)
I'd vote quite emphatically for not requiring these in the method
-- as Paul and Duncan did in the mean time.

 (Finally a really compelling reason to switch to the new method system :-) ;-)

Martin
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[Rd] Should dots be used in generic functions?
Martin Maechler