class RDoc::RI::Driver

def list_known_classes names = []
  classes = []
  stores.each do |store|
    classes << store.module_names
  end
  classes = classes.flatten.uniq.sort
  unless names.empty? then
    filter = Regexp.union names.map { |name| /^#{name}/ }
    classes = classes.grep filter
  end
  page do |io|
    if paging? or io.tty? then
      if names.empty? then
        io.puts "Classes and Modules known to ri:"
      else
        io.puts "Classes and Modules starting with #{names.join ', '}:"
      end
      io.puts
    end
    io.puts classes.join("\n")
  end
end