Question

I am studying namespace in php and Doctrine 2.2 for a week.

I explorered several blogs and read several articles about namespace in php.

I understand that, when we want to use different namepaces in different php pages, we must write: include('php page that belong namespace we want to use');

But Doctrine 2.2 doesn’t use any include or require or require_once statements for using namespace. Almost all script in Doctrine 2.2 like that :

Doctrine\ORM\EntityManager.php

<?php
namespace Doctrine\ORM;

use Closure, Exception,
    Doctrine\Common\EventManager,
    Doctrine\Common\Persistence\ObjectManager,
    Doctrine\DBAL\Connection,
    Doctrine\DBAL\LockMode,
    Doctrine\ORM\Mapping\ClassMetadata,
    Doctrine\ORM\Mapping\ClassMetadataFactory,
    Doctrine\ORM\Query\ResultSetMapping,
    Doctrine\ORM\Proxy\ProxyFactory,
    Doctrine\ORM\Query\FilterCollection;
class EntityManager implements ObjectManager
{
    /**
     * The used Configuration.
     *
     * @var \Doctrine\ORM\Configuration
    .............
    ..................................
    ..................................
    ..................................
    ..................................
?>

There isn’t any include or require statement in Doctrine 2.2.

But we run the page (Doctrine\ORM\EntityManager.php) appear fatal error,

Fatal error: Interface ‘Doctrine\Common\Persistence\ObjectManager’ not found
in C:\xampp\htdocs\www\DoctrineExplained\DoctrineORM\Doctrine\ORM\EntityManager.php on line 45

Although Doctrine 2.2 is stable version of Doctrine ORM, why doesn’t use include or require for namespaces and uses?

Answer 1

Most PHP 5.3 code out there is like that. Doctrine expects autoload to be set-up before you start using it. You can define your own __autoload() function, use spl_register_autoload() or use one of the implementations bundled with many of the frameworks out there.

This could be done for a long time too. It just took time before the conventions were adapted and namespaces pushed for that change.