# File lib/csv.rb, line 1040
  def self.generate(*args)
    # add a default empty String, if none was given
    if args.first.is_a? String
      io = StringIO.new(args.shift)
      io.seek(0, IO::SEEK_END)
      args.unshift(io)
    else
      args.unshift("")
    end
    csv = new(*args)  # wrap
    yield csv         # yield for appending
    csv.string        # return final String
  end