public function checkMapper(string $mapper): bool
    {
        if (!isset($this->$mapper)) {
            Schematic::error('Mapper '.$mapper.' not found');

            return false;
        }
        if (!$this->$mapper instanceof MapperInterface) {
            Schematic::error(get_class($this->$mapper).' does not implement MapperInterface');

            return false;
        }

        return true;
    }