protected function parseOptionString($string)
	{
		// Use the first "?" as an alias for the "optional" option
		$string = preg_replace('(^\\?)', ';optional', $string);

		$options = [];
		foreach (preg_split('#;+#', $string, -1, PREG_SPLIT_NO_EMPTY) as $pair)
		{
			$pos = strpos($pair, '=');
			if ($pos === false)
			{
				// Options with no value are set to true, e.g. {FOO;useContent}
				$k = $pair;
				$v = true;
			}
			else
			{
				$k = substr($pair, 0, $pos);
				$v = substr($pair, 1 + $pos);
			}

			$options[$k] = $v;
		}

		return $options;
	}