Get/set any class private property

Undies.php

<?php

/**
 * Access/modify any instance private property.
 */
class Undies {
    protected $instance;
    protected $setter;
    protected $getter;
    
    public function __construct($instance)
    {
        $this->instance = $instance;
        $this->getter = function($property) { return $this->{$property}; };
        $this->setter = function($property, $value) { $this->{$property} = $value; };
    }
    
    public function __get($property)
    {
        return $this->getter->call($this->instance, $property);
    }
    
    public function __set($property, $value)
    {
        $this->setter->call($this->instance, $property, $value);
    }
}


/**
 * EXAMPLE:
 * 
 * class Foo {
 *    private $privateProperty = "Hello";
 * }
 * 
 * $foo = new Foo();
 * $undies = new Undies($foo);
 * 
 * echo $undies->privateProperty; // Hello
 * $undies->privateProperty = 'Goodbye';
 * echo $undies->privateProperty; // Goodbye
 * 
 * Working example: https://3v4l.org/ib0HA
 */

Wow, learning something new. Thank you