public static function implode($array, $separator = " > ")
    {
        if ($array === null) {
            return "";
        }

        $elements = [];
        foreach($array as $rawElement) {
            $element = self::sanitizeString($rawElement);

            if ($element !== null) {
                $elements[] = $element;
            }
        }

        return implode($separator, $elements);
    }