class Fugit::Cron

def to_cron_s
  @cron_s ||= begin
    [
      @seconds == [ 0 ] ? nil : (@seconds || [ '*' ]).join(','),
      (@minutes || [ '*' ]).join(','),
      (@hours || [ '*' ]).join(','),
      (@monthdays || [ '*' ]).join(','),
      (@months || [ '*' ]).join(','),
      (@weekdays || [ [ '*' ] ]).map { |d| d.compact.join('#') }.join(','),
      @timezone ? @timezone.name : nil
    ].compact.join(' ')
  end
end