aop.php

<?php

// Test
$blaine = new Chain('Person', array(
	'firstName' => 'Blaine',
	'lastName' => 'Sch',
	'city' => 'Tulsa',
	'state' => 'Oklahoma',
	'zip' => '74107',
));
echo 'Address:' . PHP_EOL . $blaine->send('address');

// Setup
class Chain {

	public $objs = array();

	public function __construct($name, $data) {
		$obj = new $name($data);
		foreach ($obj->includes as $include) {
			$this->objs[] = new $include($this);
		}
		$this->objs[] = $obj;
	}

	public function send($method, $params = array(), $index = 0) {
		if (empty($this->objs[$index])) {
			return null;
		}
		$me = $this;
		$next = function() use($me, $method, $index) {
			return $me->send($method, func_get_args(), $index + 1);
		};
		if (!method_exists($this->objs[$index], $method)) {
			return $next();
		}
		array_unshift($params, $next);
		return call_user_func_array(array($this->objs[$index], $method), $params);
	}

	public function __call($method, $params) {
		return $this->send($method, $params, 0);
	}

	public function __get($var) {
		return $this->objs[count($this->objs)-1]->$var;
	}
}


// Real classes you create:

class Person {

	public $includes = array(
		'PersonName',
		'PersonAddress',
	);

	public $data = array();

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

	// Overwritten in PersonName
	public function name() {
		return $this->data['firstName'];
	}

}

class PersonAddress {

	public $parent = null;

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

	// Calls name() method that is overwritten
	// This method is NOT defined on the parent
	public function address() {
		return $this->parent->name() . PHP_EOL .
			$this->parent->data['city'] . ', ' . $this->parent->data['state'];
	}

}

class PersonName {

	public $parent = null;

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

	// Overwrite
	public function name($next) {
		return $next() . ' ' . $this->parent->data['lastName'];
	}

}