Zend_Loader_Autoloader introduces a comprehensive
autoloading solution for Zend Framework. It has been designed with
several goals in mind:
Provide a true namespace autoloader. (Previous incarnations intercepted all userland namespaces.)
Allow registering arbitrary callbacks as autoloaders, and manage them as a stack. (At the time of this writing, this overcomes some issues with
spl_autoload, which does not allow re-registering a callback that utilizes an instance method.)
Allow optimistic matching of namespaces to provide faster class resolution.
Zend_Loader_Autoloader implements a singleton, making it
unversally accessible. This provides the ability to register additional
autoloaders from anywhere in your code as necessary.