I have some regular expressions that i think maybe some other people would like to use (for research in bioinformatics), these regexp are very much linked to the package I'm writing but saving them as data (http://r-pkgs.had.co.nz/data.html) doesn't seem best, they would be hidden when you look at the code. I don't know what would be right thing to do or what would the good practice for exporting regexps.
The variables storing the regular expressions can be created and loaded just like the functions in your package. For example, let's say you made a file named is_foobar.R and stored it in the package's R/ subdirectory: