protected function validateArgumentLengthType(String $argument)
	{
		if (!is_numeric($argument) && !in_array($argument, ['none', 'i'])) {
			$this->cmd->error(sprintf('Failed to create runnable. [%s] is not a valid argument length type.', $argument));
		}

		if (in_array($argument, ['none', 'i'])) {
			return  "\":" . $argument . "\"";
		}

		return $argument;
	}