class RDoc::Require

def top_level
  @top_level ||= begin
    tl = RDoc::TopLevel.all_files_hash[name + '.rb']
    if tl.nil? and RDoc::TopLevel.all_files.first.full_name =~ %r(^lib/) then
      # second chance
      tl = RDoc::TopLevel.all_files_hash['lib/' + name + '.rb']
    end
    tl
  end
end