On Tue, 11 Dec 2007 12:51:52 -0800, Nishkar Grover wrote: > I'm trying to replace a built-in exception type and here's a simplified > example of what I was hoping to do... > > > >>> import exceptions, __builtin__ > >>> > >>> zeroDivisionError = exceptions.ZeroDivisionError
I don't know why you're fiddling that much with the names, `ZeroDivisionError` is a builtin name. If you do this to avoid overwriting the base classes, consider the following example:: >>> class A(object): pass ... >>> class B(A): pass ... >>> A_backup = A >>> A_backup is A True >>> class A(object): pass ... >>> A_backup is A False >>> B.__base__ is A False >>> B.__base__ is A_backup True The names really just point to an object. Once the resolution from a name to a real object is done, you can reuse the name. > >>> class Foo(zeroDivisionError): > ... bar = 'bar' > ... > >>> > >>> exceptions.ZeroDivisionError = Foo > >>> ZeroDivisionError = Foo > >>> __builtin__.ZeroDivisionError = Foo > >>> > >>> try: > ... raise ZeroDivisionError > ... except ZeroDivisionError, e: > ... print e.bar > ... > bar > >>> > >>> try: > ... 1/0 > ... except ZeroDivisionError, e: > ... print e.bar > ... > Traceback (most recent call last): > File "<stdin>", line 2, in ? > ZeroDivisionError: integer division or modulo by zero > >>> > >>> The object that ZeroDivisionError points to in your code is *not* the raised exception. > Notice that I get my customized exception type when I explicitly raise > ZeroDivisionError but not when that is implicitly raised by 1/0. It > seems like I have to replace that exception type at some lower level, > but I'm not sure how/where. Does anyone know of a way to do this? The obvious question is: What are you trying to do? Remember that you can always catch an exception in an `except` clause and perform whatever action you want, eg. raise *another* exception. If you just want to change error representations (I doubt that you really need it, tho), you might be interested in overwriting `sys.excepthook <http://docs.python.org/lib/module-sys.html#l2h-5125>`_. HTH, -- http://mail.python.org/mailman/listinfo/python-list
