protected function validateReasonPhrase($reasonPhrase) : void
	{
		if (! \is_string($reasonPhrase))
		{
			throw new \InvalidArgumentException('HTTP reason-phrase must be a string');
		}
		else if (! \preg_match(HeaderInterface::RFC7230_FIELD_VALUE, $reasonPhrase))
		{
			throw new \InvalidArgumentException(\sprintf('The given reason-phrase "%s" is not valid', $reasonPhrase));
		}
	}