<?php
namespace Foo;
throw new Exception;
In this case PHP first looks for Foo::Exception and only then for internal
Exception, but the first lookup may call __autoload (or corresponding SPL
functions) and it can emit error or throw exception.
The patch provides an additional boolean argument to __autoload() that say
if class is really required. In case if it false, user code shouldn't emit
errors or throw exceptions.
There's two problems here:
1. On each access to internal class, like Exception, SPL classes, DateTime, reflection classes, etc. - we'd have call to autoload and subsequent disk access, maybe more than one if we have include path. Performance of it would be awful.
2. All libraries having autoloaders would have to rewrite them to support the new mode.
I would propose different solution. When we have unresolved unqualified name, we do the following:
1. Check if we already know such class in namespace at compile-time. If so, it's resolved.
2. If not, will be resolved at run-time.
3. At run-time, check if we know such class in namespace now. If yes, it's resolved.
4. If not, check if we know internal class with such name. If yes, it's resolved to internal class.
5. If not, try to autoload this class. If autoloading fails, it's the undefined class error.
This rule is a bit more complex, but allows to resolve common cases without extra filesystem accesses and allows to keep autoloader without modification.
Comments?
--
Stanislav Malyshev, Zend Software Architect
stas@zend.com http://www.zend.com/
(408)253-8829 MSN: stas@zend.com