Question

The following example defines a foo class, which constructs a bar class, and stores it as a property $foo->bar. In the bar class, is it possible to reference the ‘false’ parent class, and use it’s functions?

class bar
{
    public function test_false_parent()
    {
            //Is it possible to access foo->display() from here
        {unknown code}::display();
    }
}

class foo
{
    public $bar;

    public function __construct()
    {
        $this->bar = new bar;
    }

    public function display()
    {
        echo "in";
    }
}

$foo = new foo;

$foo->bar->test_false_parent();
//Equivalent to $foo->display();

Answer 1

Not without a back reference:

class bar
{
    protected $foo;

    public function __construct(foo $foo)
    {
        $this->foo = $foo;
    }

    public function test_false_parent()
    {
        $this->foo->display();
    }
}

class foo
{
    public $bar;

    public function __construct()
    {
        $this->bar = new bar($this);
    }

    public function display()
    {
        echo "in";
    }
}

$foo = new foo;

$foo->bar->test_false_parent();