##################
##    def __call__(self, *args, **kw):
##        return self.delegate(*args, **kw)

class Hooker(Delegator):

    def __init__(self, name):
        Delegator.__init__(self)
        self.name = name

    def my_fcn(self, caller):
        print "Hooker %s called via %s" % (self.name, caller)

    def __call__(self, *args, **kw):
        self.my_fcn(*args)
        self.delegate(*args, **kw)


class Interceptor(Delegator):
    
    def __init__(self, name):
        Delegator.__init__(self)
        self.name = name

    def my_fcn(self, caller):
        print "Interceptor %s called via %s" % (self.name, caller)
        
    def __call__(self, *args, **kw):
        self.my_fcn(*args)
        #self.delegate(*args, **kw) # uncomment to propagate

def fcn(caller):
    print "Fcn at base called via %s" % caller

if __name__ == "__main__":
    bottom = Hooker("bottom")
    bottom.setdelegate(fcn)
    middle = Hooker("middle")
    middle.setdelegate(bottom)
    top = Interceptor("top")
    top.setdelegate(middle)
    print "top: ", top
    print "top.delegate: ", top.delegate
    print "calling top()... "
    top("top()")