""" Here's something I found useful when developing python programs. It takes advantage of my convention to initialize properties that I want to use in the constructor. This script checks this initialization and complains when a variable wasn't defined. Great for detecting typos early - what I like most is that when you are ready developing your script, you just throw the whole thing away from your source and you have no performance penalty. It heavily depends on the articles of Alex Martinelli: 'Constants in Python' and 'Determining Current Function Name' here at ASPN. You could beef this up with typechecking (see the comments of Philip Nunez at Alex' 'Constants...' article). Dirk Krause, firstname.lastname@example.org, 11/08/2001 """ import sys def caller(): try: raise RuntimeError except RuntimeError: exc, val, tb = sys.exc_info() frame = tb.tb_frame.f_back del exc, val, tb try: return frame.f_back.f_code.co_name except AttributeError: # called from the top return None class ObjectWithCheck: def __setattr__(self, name, value): c = caller() if c == '__init__' or hasattr(self, name): self.__dict__[name] = value else: raise TypeError, self.__class__.__name__ + 'error: variable was not declared!' class myObjWithCheck(ObjectWithCheck): def __init__(self): self.somevariable = 0 class myObjWithoutCheck: def __init__(self): self.somevariable = 0 o = myObjWithoutCheck() o.somevariable = 2 o.somevaiable = 2 # This line seems ok ... o = myObjWithCheck() o.somevariable = 2 o.somevaiable = 2 # ... this line raises an error!