Peter Otten wrote: > Then you have modified the code posted by Steven Bethard. > > Oops. Indeed I did. I changed this
>>> class Observable(object): ... def __init__(self, func, instance=None, observers=None): ... if observers is None: ... observers = [] ... self.func = func ... self.instance = instance ... self.observers = observers to this >>> class Observable(object): ... def __init__(self, func, instance=None, observers=None): ... self.func = func ... self.instance = instance ... self.observers = observers or [] >> I don't see how your behaviour should come about ... a new observer-list >> is created for every decorated method, so there is no problem. >> > > Yes, but that list is shared across instances of SomeActor. > Oh! I thought a new Observable-object is created for every *instance* of SomeActor, where there is actually only one Observable per method that decorates *all* methods (all meth() methods, that is). Am I right? And I seem to have accidentally "solved" this by rewriting the __init__() method the way I did. Now it creates a new list even when it gets passed an empty list. How very smart of me ... ;) Looking at the way it is going to be used, I don't see a problem with this. Or am I missing something that could stab me in the back here? Thanks for the thorough explanation. But you *did* mock me with that "SomeActor.meth is SomeActor.meth"-line, right? ;) > > If you want per-instance callbacks you have to store the observers list (or > the bound method) in the instance: > > >>>> class SomeActor(object): >>>> > ... def __init__(self): > ... self.meth = Observable(self.meth, self) > ... def meth(self, foo): print foo > Seems good, but I'm trying to take as much hassle out of the programmer (probably me, mostly) as possible in order to watch method calls. Simply sticking a decorator in front of a methos, with no arguments, no nothing, seems less prone to errors. Also, reading "self.meth = Observable(self.meth, self)" kinda makes sense now, but I *know* I'd be scratching my head about this in no less than a few weeks. BTW, that might be my single favorite line of python code so far ... :) /W -- http://mail.python.org/mailman/listinfo/python-list
