From sfalcon at fhcrc.org  Wed May 23 14:45:41 2007
From: sfalcon at fhcrc.org (Seth Falcon)
Date: Wed, 23 May 2007 05:45:41 -0700
Subject: [Rd] relist, an inverse operator to unlist
In-Reply-To: <20070522115154.GS28199@econ.upenn.edu> (Andrew Clausen's message
	of "Tue, 22 May 2007 07:51:54 -0400")
References: <20070513172911.GP6923@econ.upenn.edu>
	<971536df0705131602p2e407fa2sd1d5e6984d2ffa56@mail.gmail.com>
	<20070514043240.GL28199@econ.upenn.edu>
	<971536df0705132354u6e2ae0cci9b1e42a766dc0ec5@mail.gmail.com>
	<17992.5499.383704.358418@stat.math.ethz.ch>
	<20070519153636.GJ21178@econ.upenn.edu>
	<20070519160413.GK21178@econ.upenn.edu> <m2r6p990j5.fsf@ziti.local>
	<20070522115154.GS28199@econ.upenn.edu>
Message-ID: <m2y7jf3dze.fsf@ziti.local>

Andrew Clausen <clausen at econ.upenn.edu> writes:

> Hi Seth,
>
> On Mon, May 21, 2007 at 05:15:10PM -0700, Seth Falcon wrote:
>> I will also add that the notion of a default argument on a generic
>> function seems a bit odd to me.  If an argument is available for
>> dispatch, I just don't see what sense it makes to have a default.  In
>> those cases, the default should be handled by the method that has a
>> signature with said argument matching the "missing" class.
>> 
>> What often does make sense is to define a generic function where some
>> argument are not available for dispatch.  For example:
>> 
>> setGeneric("foo", signature="flesh",
>>            function(flesh, skeleton=attr(flesh, "skeleton") 
>>                standardGeneric("foo")))
>
> That's an excellent suggestion.  Thanks!  However, I had to set the signature
> to c("numeric", "missing") rather than just "numeric".
>
> I have uploaded a new version here:
>
> 	http://www.econ.upenn.edu/~clausen/computing/relist.R

I misunderstood.  You aren't using S4 classes/methods at all
and so I don't actually see how my comments could have been helpful in
any way.  relist seems like a really odd solution to me, but based on
the discussion I guess it has its use cases.

Best,

+ seth



-- 
Seth Falcon | Computational Biology | Fred Hutchinson Cancer Research Center
http://bioconductor.org



[Rd] relist, an inverse operator to unlist
Seth Falcon