Hrvoje Niksic wrote: > The documentation of the mro() method on the class object says: > > class.mro() > This method can be overridden by a metaclass to customize the method > resolution order for its instances. It is called at class > instantiation, and its result is stored in __mro__. > > Am I interpreting it correctly that the "__mro__" attribute is intended > to be used directly, while the "mro" method is intended to be optionally > overridden by the metaclass implementor?
Looks like you're right: >>> class T(type): ... def mro(self): ... r = type.mro(self) ... print r ... return r[::-1] ... >>> class A: ... __metaclass__ = T ... [<class '__main__.A'>, <type 'object'>] >>> A.__mro__ (<type 'object'>, <class '__main__.A'>) > If that is the case, it sounds exactly the opposite to the normal python > convention that __methods__ are part of the protocol, and > underscore-less functions or methods are meant to be called by the end > user of the class. While I'm not aware of any cases where obj.foo() translates to obj.__foo__() internally make_mro() might still have been a more appropriate name. Peter -- http://mail.python.org/mailman/listinfo/python-list
