[R] "Old" libraries with new R?

[Prof Brian Ripley]

On Tue, 16 Sep 2003, Uwe Ligges wrote:

> (Ted Harding) wrote:
> 
> > Hi Folks,
> > 
> > I'm currently installing R-1.7.1 off CRAN.
> > 
> > As it happens, I have a CD (kindly made for me by Linux
> > Emporium) containing all the libraries which were on CRAN
> > early this year when I installed R-1.6.1. This is highly
> > convenient, since the alternative would be several hours
> > on-line.
> > 
> > While a recent library will on installation announce the
> > fact should it need a newer version of R than the one which
> > is installed, presumably this is not likely to be the case
> > for an old library if a newer version of R is incompatible
> > with it.
> > 
> > So is there a way of finding out whether a library dating
> > from some time back is compatible with a recent R, other than
> > simply trying it out to see if it works OK?
> > 
> > With thanks, and best wishes to all,
> > Ted.
> > 
> > 
> 
> There is a dependency field in a package's DESCRIPTION file. Here the 
> package author *might* give information on dependency for a minimal 
> required R version. But this is not checked, and the author not always 
> knows about dependencies, because he/she is probably developing on 
> recent versions.

I think Ted wants the reverse: will an old package source work with
current R?  That would need prescience beyond most package authors to know 
at the time the package was bundled.

The best think to do I believe is to first check if the version you have
is the same as that on CRAN, and if not try R CMD check on the old
package.  (If yes, you could check 
http://cran.r-project.org/src/contrib/checkSummary.html to see if it works 
on the CRAN machines.)

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595