PHP_Expando

PHP_Expando is a library that allows adding methods to classes or objects using a neat closure syntax.

How does it work

PHP_Expando provides an autoloader that injects a metaclass property (both static and object scope). The metaclass when used gives you a reference to the an Expando Metaclass which allows you to add methods, much in the faction of prototypes in Javasript.

Registering the loader

<?php
require_once 'PHP/Expando/Loader.php';
\PHP\Expando\Loader::register();

Usage with class scope

<?php

\MyClass::$metaclass->hello = function() {
    return 'Hello, World!';
};
$class = new \MyClass;
assertSame('Hello, World!', $class->hello());

Usage with object scope

<?php

$class = new \MyClass;
$class->metaclass->hello = function() {
    return 'Hello, World!';
};
assertSame('Hello, World!', $class->hello());

Append to method

<?php

$class = new \MyClass;
$class->metaclass->hello = function($name) {
    $greeting = "Hello, $name!";
};
$class->metaclass->appendToMethod('hello', 'return $greeting;');
assertSame('Hello, John!', $class->hello('John'));

Prepend to method

$class = new \MyClass;
$class->metaclass->hello = function($greeting) {
    return $greeting;
};
$class->metaclass->prependToMethod('hello', '$greeting = "Hello, $greeting!";');
assertSame('Hello, John!', $class->hello('John'));