MongoLite\Database::registerCriteriaFunction PHP Method

    public function registerCriteriaFunction($criteria)
    {
        $id = uniqid("criteria");
        if (is_callable($criteria)) {
            $this->document_criterias[$id] = $criteria;
            return $id;
        }
        if (is_array($criteria)) {
            $this->document_criterias[$id] = create_function('$document', 'return ' . UtilArrayQuery::buildCondition($criteria) . ';');
            return $id;
        }
        return null;
    }