function array_search_string($needle, array $haystack)
{

	$found = false;
	if (strpos($needle, '[') !== false) {
		$k = preg_split('~\]?\[~', substr($needle, 0, -1));
		$i = 1;
		$t = count($k);
		foreach ($k as $k) {
			if ((array)$haystack === $haystack) {
				if (array_key_exists($k, $haystack)) {
					$haystack = $haystack[$k];
					$i === $t && ($found = true);
				}
			}
			++$i;
		}
	} elseif (array_key_exists($needle, $haystack)) {
		$haystack = $haystack[$needle];
		$found = true;
	} else {
		$haystack = null;
	}
	return $found ? $haystack : null;

}