<?php

class Foo
{
    private $value;
    
    public function __construct($value)
    {
        $this->value = $value;
    }
}

$foo = new Foo('string');

// Instead of bind to closure you can use call in php 7
$closure = function() {
    return md5($this->value);
};

var_dump($closure->call($foo));


string(32) "b45cffe084dd3d20d928bee85e7b0f21"

• Updating a document in MongoDB
• Influence var_dump output of an object in PHP
• Filtering elements of an Iterator

PHP 7.2, Zend 3.0, Symfony 4.0, Laravel 5.6, PHPUnit 6.5, Doctrine 2.8