public function offsetSet($offset, $value)
    {
        switch ($this->type) {
            case GPBType::SFIXED32:
            case GPBType::SINT32:
            case GPBType::INT32:
            case GPBType::ENUM:
                GPBUtil::checkInt32($value);
                break;
            case GPBType::FIXED32:
            case GPBType::UINT32:
                GPBUtil::checkUint32($value);
                break;
            case GPBType::SFIXED64:
            case GPBType::SINT64:
            case GPBType::INT64:
                GPBUtil::checkInt64($value);
                break;
            case GPBType::FIXED64:
            case GPBType::UINT64:
                GPBUtil::checkUint64($value);
                break;
            case GPBType::FLOAT:
                GPBUtil::checkFloat($value);
                break;
            case GPBType::DOUBLE:
                GPBUtil::checkDouble($value);
                break;
            case GPBType::BOOL:
                GPBUtil::checkBool($value);
                break;
            case GPBType::BYTES:
                GPBUtil::checkString($value, false);
                break;
            case GPBType::STRING:
                GPBUtil::checkString($value, true);
                break;
            case GPBType::MESSAGE:
                if (is_null($value)) {
                  trigger_error("RepeatedField element cannot be null.",
                                E_USER_ERROR);
                }
                GPBUtil::checkMessage($value, $this->klass);
                break;
            default:
                break;
        }
        if (is_null($offset)) {
            $this->container[] = $value;
        } else {
            $count = count($this->container);
            if (!is_numeric($offset) || $offset < 0 || $offset >= $count) {
                trigger_error(
                    "Cannot modify element at the given index",
                    E_USER_ERROR);
                return;
            }
            $this->container[$offset] = $value;
        }
    }