Ипатьев

class A
{
    function execute($function, $params) {
        return [$this,$function](...$params);
    }
    function payload($param) {
        return $param * $param;
    }
}
$a = new A;
echo $a->execute('payload', [5]);

abstract class BasicTableGateway
{
    protected $db;
    protected $table;
    protected $fields;
    protected $primary = 'id';

    public function __construct(\PDO $db)
    {
        $this->db = $db;
    }
    public function read($id): ?array
    {
        $stmt =$this->db->prepare("SELECT * FROM `$this->table` WHERE `$this->primary`=?");
        $stmt->execute([$id]);
        return $stmt->fetch();
    }
    public function insert($data): int
    {
        $this->validate($data);

        $fields = '`'.implode("`,`", array_keys($data)).'`';
        $placeholders = str_repeat('?,', count($data) - 1) . '?';
        $sql = "INSERT INTO `$this->table` ($fields) VALUES ($placeholders)";
        $this->db->prepare($sql)->execute(array_values($data));
        return $this->db->lastInsertId();
    }
    protected function validate($data)
    {
        $diff = array_diff(array_keys($data), $this->fields);
        if ($diff) {
            throw new \InvalidArgumentException("Unknown field(s): ". implode($diff));
        }
    }
}

class UserGateway extends BasicTableGateway {
    protected $table = 'gw_users';
    protected $fields = ['email', 'password', 'name', 'birthday'];
}
$userGateway = new UserGateway($pdo);
$data = [
    'email' => 'foo@bar.com',
    'password' => 123,
    'name' => 'Fooster',
];
$id = $userGateway->insert($data);
$user = $userGateway->read($id);
echo json_encode($user),PHP_EOL;