I have started work on a new module that would allow the decoration of class methods to restrict access based on calling context. Specifically, I have created 3 decorators named public, private and protected.
These modifiers work as follows: Private: A private method can only be called from a method defined in the same class as the called method. Protected: A protected method can only be called from a method defined in the same or class derived from the called method's class. Public: No access restrictions (essentially a no-op). Programmers with a C++ or Java background will be familiar with these concepts in those languages; these decorators attempt to emulate their behavior Bugs: 1) These decorators will not tolerate other decorators because they examine the call stack in order to determine the caller's frame. A second decorator, either before or after the access decorator will insert a stack frame, which the current version of these decorators cannot handle. Making sure decorators set their wrapper functions __name__, __doc__ and append to its dictionary would be required at least for interoperability. 2) As noted, staticmethod and classmethod cannot be handled by the access decorators, not only because they are decorators themselves, but because the current access decorators require access to an instance of the class (self) in order to do method resolution. classmethod support could probably be added without too much difficulty but staticmethods, because they have no self or cls, would be difficult. 3) Friend classes, as defined in C++. These would probably be defined as a class-level list of classes that may have private/protected access to the given class's internals. This should not be too hard to add. 4) Decorators for member variables -- these decorators can already be applied to get_* and set_* methods for properties. Overriding __getattr__ may be a better solution for attribute access, however. Source available at: http://starship.python.net/crew/timehorse/access.py Jeffrey -- http://mail.python.org/mailman/listinfo/python-list
