This is R html help files, not rdoc.
Unless your "rdoc" is different than the "rdoc" I know, which is the Ruby documentation utility.
On Dec 15, 2006, at 11:09 PM, hadley wickham wrote:
It could happen that the structure of a help file is inconsistent, i.e. no 'Usage' header. If so, now it outputs the first 1100 character of the help as plain text. Maybe you find what do you are looking for.
I'm pretty sure usage is required in rdoc files.