protected static function constantSuffix($structName, $value, $index)
    {
        $key = mb_strtoupper($structName . '_' . $value);
        $indexedKey = $key . '_' . $index;
        if (array_key_exists($indexedKey, self::$uniqueConstants)) {
            return self::$uniqueConstants[$indexedKey];
        } elseif (!array_key_exists($key, self::$uniqueConstants)) {
            self::$uniqueConstants[$key] = 0;
        } else {
            self::$uniqueConstants[$key]++;
        }
        self::$uniqueConstants[$indexedKey] = self::$uniqueConstants[$key];
        return self::$uniqueConstants[$key];
    }