What is the general feeling about reserving a namespace for PHP's built in classes?
As the number of built-in classes grows over time, the chances of naming collisions with user classes will grow. When naming conflicts occur, they happen in an unexpected way, that does not make it readily obvious that a name conflict has occurred. That's because most projects use auto loaders, and the auto loader only runs if a class is unregistered. If a user creates a class called "Directory" and places it in the auto load path, then tries to instantiate it, they will *not* receive any error. If the user then tries to call Directory::MyMethod(), they are told that the method doesn't exist, even when they are staring at the class definition. The user presumes that the auto loader has found and loaded the class, because there isn't a "class not found" message. If new built-in classes are added in the future using common dictionary words as the name, there is a good chance of confusing breaks when the PHP version is updated. Now that namespaces are a thing in PHP, maybe we should take a page from C++'s book and have users include the standard library classes they want, when they need them. ie: use \spl\Directory; I'm also wondering if there would be any performance benefit to not having a bunch of internal classes pre-registered "just in case".
