aspect oriented programming with traits in php

aop.php

<?php

/**
 * AOP Trait
 * Used to created aop for your class.
 */
trait AOP {

	public $filters = array();

	public function applyFilter($method, $function) {
		if (empty($this->filters[$method])) {
			$this->filters[$method] = array();
		}
		return $this->filters[$method][] = $function;
	}

	public function _filter($method, $params, $callback) {
		$callbacks = $this->filters[$method];
		$callbacks[] = $callback;
		$queue = new AOPChain($this, $callbacks);
		return $queue->first($params);
	}

}

/**
 * Responsible for creating the chain queue and processing it
 */
class AOPChain {

	public $host = null; // Object that has the filter

	public $callbacks = array(); // array of callbacks

	public function __construct($host, $callbacks) {
		$this->host = $host;
		$this->callbacks = $callbacks;
		$this->position = 0;
	}

	// Helps with the first item in the chain by prependig known variables
	public function first($params) {
		return $this->next($this->host, $params, $this);
	}

	// called inside of a filter `$chain->next($self, $params, $chain);`
	public function next($self, $params, $chain) {
		return call_user_func($this->callbacks[$this->position++], $self, $params, $chain);
	}

}

class Person {

	use AOP;

	public function address($name, $location) {
		return $this->_filter(__FUNCTION__, compact('name', 'locations'), function($self, $params, $chain) {
			echo 'Hello: '. $params['name'];
		});
	}

}

$foo = new Person();

$foo->applyFilter('address', function($self, $params, $chain) {
	try {
		$data = $chain->next($self, $params, $chain);
	} catch (Exception $e) {
		echo 'you caught something';
	}
});


echo $foo->address('blaine', 'tulsa');