[R] build R source package in place from CVS?

[Andrew Piskorski]

I'm currently using R CMD INSTALL to build and install some of my own
custom R packages.  Basically, I use a script which first builds a
tarball of my R source code, and then calls R CMD INSTALL, which
builds and installs that source package from the tarball, including
re-compiling all my C code from scratch every single time, which is
both totally unneccessary and tediously slow.

What I would like to do instead (and what I do in fact do with S-Plus)
is simply cd to the directoy where the production copy of my R package
lives, do a CVS update, and then rebuild my R package right there in
that directory.  I do not want to generate any intermediary tarballs
nor copy the package files to any other locations.

Is there any current way to build R packages in place like that?  Or
if not, how would you suggest I go about accomplishing this?

Thanks!

-- 
Andrew Piskorski <atp at piskorski.com>
http://www.piskorski.com/