Do you understand PHP garbage collection? What is the result of each of the gist files?

file1.php

<?php

class foo
{
    public $bar = 1;

    function bar()
    {
        echo $this->bar;
    }
}

class faz
{
    public $baz = 2;
    function bar()
    {
        echo $this->baz;
    }
}

$foo = new foo();
$faz = new faz();

$bar = &$foo;
$baz = $faz;

$bar->bar = 4;
$baz->baz = 5;

$bar = $baz;
$baz = null;

$faz->bar();
$foo->bar();

file2.php

<?php

class foo
{
    public $bar = 1;

    function bar()
    {
        echo $this->bar;
    }
}

class faz
{
    public $baz = 2;
    function bar()
    {
        echo $this->baz;
    }
}

$foo = new foo();
$faz = new faz();

$bar = &$foo;
$baz = $faz;

$bar->bar = 4;
$baz->baz = 5;

$bar = null;
$baz = null;

$faz->bar();
$foo->bar();

gistfile1.txt

If you answered wrongly any of the results above, you really should read this:

http://php.net/manual/en/language.references.php