Romaric Drigon romaricdrigon

Why objects (usually) use less memory than arrays in PHP

This is just a small post in response to [this tweet][tweet] by Julien Pauli (who by the way is the release manager for PHP 5.5). In the tweet he claims that objects use more memory than arrays in PHP. Even though it can be like that, it's not true in most cases. (Note: This only applies to PHP 5.4 or newer.)

The reason why it's easy to assume that objects are larger than arrays is because objects can be seen as an array of properties and a bit of additional information (like the class it belongs to). And as array + additional info > array it obviously follows that objects are larger. The thing is that in most cases PHP can optimize the array part of it away. So how does that work?

The key here is that objects usually have a predefined set of keys, whereas arrays don't:

A. Documentation

We are working on a framework, is mandatory that you have read the framework doc:

Locate the section for your github remote in the .git/config file. It looks like this:

[remote "origin"]
	fetch = +refs/heads/*:refs/remotes/origin/*
	url = [email protected]:joyent/node.git

Now add the line fetch = +refs/pull/*/head:refs/remotes/origin/pr/* to this section. Obviously, change the github url to match your project's URL. It ends up looking like this:

Symfony2.1. How to integrate assetic lessphp filter.

Add the following package to your composer.json:

"require": {
    ...
    "leafo/lessphp": "dev-master",
 ...

	<!DOCTYPE html>
	<html>
	<head>
	<meta name="viewport" content="initial-scale=1.0, user-scalable=no"/>
	<script type="text/javascript" src="http://maps.google.com/maps/api/js?sensor=true"></script>
	<script type="text/javascript" src="http://mbostock.github.com/d3/d3.js?1.29.1"></script>
	<style type="text/css">

	html, body, #map {
	width: 100%;

	imports:
	# ....
	- { resource: services/session.yml }


	framework:
	# ....
	session:
	handler_id: session.handler.memcached

	<?php

	/*
	* This file is part of the Symfony package.
	*
	* (c) Fabien Potencier <[email protected]>
	*
	* For the full copyright and license information, please view the LICENSE
	* file that was distributed with this source code.
	*/

	<?php

	namespace Dpn\ToolsBundle\Form\Type;

	use Symfony\Component\Form\AbstractType;
	use Dpn\ToolsBundle\Form\DataTransformer\EntityToIdTransformer;
	use Symfony\Component\Form\FormBuilderInterface;
	use Symfony\Component\OptionsResolver\OptionsResolverInterface;
	use Doctrine\Common\Persistence\ObjectManager;

	<?php

	class TxController extends Controller
	{
	public function context($id)
	{
	return new TxProxy($this->get($id), $this->get('doctrine.orm.default_entity_manager'));
	}
	}

	/**
	* Take screenshot when step fails.
	* Works only with Selenium2Driver.
	*
	* @AfterStep
	*/
	public function takeScreenshotAfterFailedStep($event)
	{
	if (4 === $event->getResult()) {
	$driver = $this->getSession()->getDriver();