Something like a callback delegate function in php

Question

I would like to implement something similar to a c# delegate method in PHP. A quick word to explain what I\'m trying to do overall: I am trying to implement some asynchron

Answer 1

I was wondering if we could use __invoke magic method to create "kind of" first class function and thus implement a callback

Sound something like that, for PHP 5.3

interface Callback 
{
    public function __invoke(); 
}

class MyCallback implements Callback
{
    private function sayHello () { echo "Hello"; }
    public function __invoke ()  { $this->sayHello(); } 
}

class MySecondCallback implements Callback
{
    private function sayThere () { echo "World"; }
    public function __invoke ()  { $this->sayThere(); }
}

class WhatToPrint
{
    protected $callbacks = array();
    public function register (Callback $callback) 
    {
        $this->callbacks[] = $callback;
        return $this;
    }
    public function saySomething ()
    {
        foreach ($this->callbacks as $callback) $callback(); 
    }
}

$first_callback = new MyCallback;
$second_callback = new MySecondCallback;
$wrapper = new WhatToPrint;
$wrapper->register($first_callback)->register($second_callback)->saySomething();

---

Will print HelloWorld

Hope it'll help ;)

But I'd prefer the Controller pattern with SPL for such a feature.