Check whether a value or array of values are the only existing values within an array

in_array_exclusively.php

function in_array_exclusive($needles, $haystack) {
	$keys = count($haystack);
	if(is_array($needles)) {
		foreach($needles as $needle) {
			if(!in_array($needle, $haystack)) {
				return false;
			} else {
				$keys = $keys - 1;
			}
		}
	} else {
		if(!in_array($needles, $haystack)) {
			return false;
		} else {
			$keys = $keys - 1;
		}
	}
	if($keys == 0) {
		return true;
	}
	return false;
}