Prevent decorator from being used twice on the same function in python

Question

I have a decorator:

from functools import wraps
def d(f):
    @wraps(f)
    def wrapper(*args,**kwargs):
        print \'Calling func\'
        return f(*arg         


        

Answer 1

I'll also propose my solution:

first, create another decorator:

class DecorateOnce(object):
    def __init__(self,f):
        self.__f=f
        self.__called={} #save all functions that have been decorated 
    def __call__(self,toDecorate):
        #get the distinct func name
        funcName=toDecorate.__module__+toDecorate.func_name
        if funcName in self.__called:
            raise Exception('function already decorated by this decorator')
        self.__called[funcName]=1
        print funcName
        return self.__f(toDecorate)

Now every decorator you decorate with this decorator, will restrict itself to decorate a func only once:

@DecorateOnce
def decorate(f):
    def wrapper...