[R] source-only package, but still: Error: package 'simple' was built for powerpc-apple-darwin7.9.0

[Paul Shannon]

Hi Brian, 

Thanks very much for your two tips concerning my failed attempt, yesterday, to build and
install a package:

 "I suspect your package has structure it is not using."

     I had an empty 'src' directory.  Once I removed that, BUILD & INSTALL on another
     OS worked fine.

  "We encourage you to use a repository, as in the article in the current R-news."

I've spent a few hours on this, and though I made some pretty good progress, I am not
yet completely successful.  I read your article, "Packages and their Management in R 2.1.0" 
and the two antecedents, "R Help Desk, 12/03" and "Writing R Extensions".  I also
attempted some reverse-engineering by studying directory structure at the CRAN repository.

I can now use

   available.packages (contriburl='http://myhost/R')

and see the simple package I installed there, but I cannot load it unless
(this is embarrassing...) I have two copies of the tar.gz file, one at
the root of the repository, and one in src/contrib within the repository.

I am sure that the repository mechanism is sensible, but I am also sure I don't yet
understand it.  The directory structure, and the roles of the PACKAGES, replisting, and
repdatadesc.rda are as yet unclear to me.

Can you provide some further help?  I'll be grateful.

For what it's worth (and assuming it doesn't yet exist) I would be glad, at the conclusion 
of this exercise, to create a step-by-step tutorial, titled, perhaps: 

  "Sharing Code: An Idiot's Guide to packaging an R function, creating a repository, and
   installing from that repository into a local library."

Regards,

 - Paul Shannon
   Institute for Systems Biology
   Seattle