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

Noam, The property of func_code to use is co_name. See below, all that is changed is two lines at top of d()'s def

def d(f):
   if f.func_code.co_name == 'wrapper':
      return f    #ignore it  (or can throw exception instead...)
   @wraps(f)
   def wrapper(*args, **kwargs):
      print 'calling func'
      return f(*args, **kwargs)
   return wrapper

Also, see for Lukáš Lalinský's approach which uses a explicitly defined property attached to the function object. This may be preferable as the "wrapper" name may be used elsewhere...