Constructor Overloading

A library which allows you to have constructor overloading in PHP >=5.3 projects. This is simply done using: type hint, default value and PHP doc.

Usage

In order to use the library it's best recommended to follow some rules. The library is looking for any private / protected methods width start with _construct in your class. Among these methods the best candidate is picked up. In order to help the library to find the best candidate you shall follow these rules:

1. If your argument is an object, use type hint (example: function(A $a)).
2. Otherwise, the argument is a primitive and in this case if it has a default value, then you can use it to hint its type (example: function ($int = 0)).
3. Otherwise you can use PHP doc (example: @param int $int)

** In case of a primitive has default value and PHP doc the default value will be preferred over the PHP doc.

Examples

First, in order to use the library, one must register the autoloader:

<?php

use ConstructorOverloading\ConstructorOverloading;
$pathToConstructorOverloading = __DIR__ . '/ConstructorOverloading';
require_once $pathToConstructorOverloading . '/ConstructorOverloading.php';
$constructorOverloading = new ConstructorOverloading();
$constructorOverloading->registerAutoloader();

Then, let's say you have a class called Rectangle which can be constructed by either width and height or by size (square):

<?php

use ConstructorOverloading\Dispatcher;

class Rectangle
{
    private $width, $height;

    public function __construct()
    {
        $dispatcher = new Dispatcher();
        $dispatcher->dispatch($this, func_get_args());
    }

    /**
     * @param int $width
     * @param int $height
     */
    protected function _constructWidthAndHeight($width, $height)
    {
        $this->width = $width;
        $this->height = $height;
    }

    /**
     * @param int $size
     */
    protected function _constructSize($size)
    {
        $this->width = $this->height = $size;
    }
}

Now, if you use:

$rectangle = new Rectangle(10, 20);

The _constructWidthAndHeight will be invoked and result in width = 10, height = 20

And, if you use:

$rectangle = new Rectangle(30);

The _constructSize will be invoked and result in width = height = 30