[Rd] relist, an inverse operator to unlist

Martin Maechler maechler at stat.math.ethz.ch
Tue May 22 19:41:34 CEST 2007

>>>>> "AndrewC" == Andrew Clausen <clausen at econ.upenn.edu>
>>>>>     on Tue, 22 May 2007 07:51:54 -0400 writes:

    AndrewC> Hi Seth,
    AndrewC> 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")))

    AndrewC> That's an excellent suggestion.  Thanks!  However, I had to set the signature
    AndrewC> to c("numeric", "missing") rather than just "numeric".

    AndrewC> I have uploaded a new version here:

    AndrewC> http://www.econ.upenn.edu/~clausen/computing/relist.R

This looks "good from far".

I won't have time to do anything more about it for the next few
Please remind me (in private) about it if you don't hear back
within one week.


    AndrewC> Cheers,
    AndrewC> Andrew

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