python: subclass a metaclass
- by Michael Konietzny
Hello,
for putting methods of various classes into a global registry I'm using a decorator with a metaclass. The decorator tags, the metaclass puts the function in the registry:
class ExposedMethod (object):
def __init__(self, decoratedFunction):
self._decoratedFunction = decoratedFunction
def __call__(__self,*__args,**__kw):
return __self._decoratedFunction(*__args,**__kw)
class ExposedMethodDecoratorMetaclass(type):
def __new__(mcs, name, bases, dct):
for obj_name, obj in dct.iteritems():
if isinstance(obj, ExposedMethod):
WorkerFunctionRegistry.addWorkerToWorkerFunction(obj_name, name)
return type.__new__(mcs, name, bases, dct)
class MyClass (object):
__metaclass__ = DiscoveryExposedMethodDecoratorMetaclass
@ExposeDiscoveryMethod
def myCoolExposedMethod (self):
pass
I've now came to the point where two function registries are needed. The first thought was to subclass the metaclass and put the other registry in. For that the new method has simply to be rewritten.
Since rewriting means redundant code this is not what I really want. So, it would be nice if anyone could name a way how to put an attribute inside of the metaclass which is able to be read when new is executed. With that the right registry could be put in without having to rewrite new.
Thanks and Greetings,
Michael
