This section lists standard predefined classes. Miscellaneous extensions define other classes which are described in their reference.
These classes are defined in the standard set of functions included in the PHP build.
Created by dir().
A generic empty class created as a result of typecasting to object or various standard functions.
Possibly created by unserialize().
The predefined final class Closure is used for representing anonymous functions.
The predefined final class Generator is used for representing generators.
Following identifiers may not be used as a class name as they have special purpose.