[R-SIG-Mac] Package management in R

[David Winsemius]

On Sep 28, 2015, at 10:38 PM, Chris Yang wrote:

> Hello,
> 
> I am new to R and just installed R and RStudio on a Mac.
> 
> I have a question about managing packages in R. I wonder if there is
> the need and functionality to periodically clean up packages installed
> via RStudio, e.g. older versions, files downloaded for installation,
> etc. Does the update remove the older version completely before
> installing a new one? And what about installation from source?
> 
> I ask because Homebrew (a package manager for OS X) keeps older
> versions of a package and the files necessary for past installations
> upon updates but it offers a command to clean up these stuff too. I
> wonder if it is the same for R.

If you have older versions of R in a Framework directory tree, those packages are kept but if you update a package in the current major version it will be over-written. That is not a Mac specific behavior. 

You may be able to recover older versions with a Time Machine copy, but I'm not clear why you would want to do so. You can also pull source copies of earlier package version in the CRAN archives.

-- 
David Winsemius
Alameda, CA, USA