Allow modification of object only upon creation

Person.php

<?php

class Person
{
    private $firstName;
    private $lastName;

    private function __construct()
    {

    }

    public function getFirstName()
    {
        return $this->firstName;
    }

    public function getLastName()
    {
        return $this->lastName;
    }

    public static function create()
    {
        $instance = new static();

        return new PersonEditor($instance, function($field, $value) use ($instance) {
            $instance->$field = $value;
        });
    }
}

class PersonEditor
{
    private $editor;
    private $instance;

    public function __construct(Person $instance, Closure $editor)
    {
        $this->instance = $instance;
        $this->editor = $editor;
    }

    public function setFirstName($firstName)
    {
        call_user_func_array($this->editor, ['firstName', $firstName]);
    }

    public function setLastName($lastName)
    {
        call_user_func_array($this->editor, ['lastName', $lastName]);
    }

    public function getInstance()
    {
        return $this->instance;
    }
}


$personEditor = Person::create();
$personEditor->setFirstName('Moein');
$personEditor->setLastName('Akbarof');
$person = $personEditor->getInstance();
var_dump($person->getFirstName(), $person->getLastName());