private function validateArray(array $array): bool
  {
    foreach ($array as $element)
    {
      if (is_array($element))
      {
        $tmp = $this->validateArray($element);
        if ($tmp===true)
        {
          return true;
        }
      }
      else
      {
        if ($element!==null && $element!==false && $element!=='')
        {
          return true;
        }
      }
    }

    return false;
  }