How do you update your R? I mean the whole thing, not just the base packages.

R comes with a library folder where packages go – both the base packages and the user-written ones you install over time. I’m not entirely sure what would be the best place for this folder so updates to all packages are as easy as possible.

It gets worse. On a Mac you have not one, but n+2 library folders. One is /Library/Frameworks/R.framework/Resources/library. Let’s call it (1). The other n+1 are as many as there are historic versions of R on your computer, plus one. All are in /Library/Frameworks/R.framework/Versions/. In my case, they are as follows: n of them are in X/Resources/library, where X is 2.13, 2.14, and 2.15; one is in Current/Resources/library.

I know that the three library folders in X=2.15, Current and (1) are identical and updated simultaneously, though only the first shows up when I call .libPaths(). But when you update say, from 2.15 to 2.16, your historic versions remain frozen and the new (1) and Current folders reflect only 2.16. You have to install non-base packages all over again, by hand. Or do you? Is there a way to script an update of everything in the library folder at version t-1 when you update your R to version t? If anybody knows, please drop a comment. Thank you.