making PLIST conditional based on options?

["Steven M. Bellovin" <smb%cs.columbia.edu@localhost>]

I'm creating a package where one file may or may not be installed,
depending on option settings.  What's the best way to do that?  Have a
PLIST.withoption and a PLIST.withoutoption, and set PLIST_SRC
conditionally?

                --Steven M. Bellovin, http://www.cs.columbia.edu/~smb