GraphQL\Utils\MixedStore::offsetSet PHP Метод

    public function offsetSet($offset, $value)
    {
        if (is_scalar($offset)) {
            $this->scalarStore[$offset] = $value;
        } else {
            if (is_object($offset)) {
                $this->objectStore[$offset] = $value;
            } else {
                if (is_array($offset)) {
                    $this->arrayKeys[] = $offset;
                    $this->arrayValues[] = $value;
                } else {
                    throw new \InvalidArgumentException("Unexpected offset type: " . Utils::printSafe($offset));
                }
            }
        }
    }