Path: csiph.com!fu-berlin.de!uni-berlin.de!not-for-mail
From: "Sven R. Kunze" <srkunze@mail.de>
Newsgroups: comp.lang.python
Subject: Re: monkey patching __code__
Date: Fri, 18 Mar 2016 15:42:01 +0100
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On 18.03.2016 15:33, Sven R. Kunze wrote:
> On 18.03.2016 15:23, Ian Kelly wrote:
>> On Fri, Mar 18, 2016 at 7:47 AM, Ian Kelly <ian.g.kelly@gmail.com> 
>> wrote:
>>> Your patched version takes two extra arguments. Did you add the
>>> defaults for those to the function's __defaults__ attribute?
>> And as an afterthought, you'll likely need to replace the function's
>> __globals__ with your own as well.


def f(a, b=None, c=None):
     print(a, b, c)

def f_patch(a, b=None, c=None, d=None, e=None):
     print(a, b, c, d, e)


f.__code__ = f_patch.__code__
f.__defaults__ = f_patch.__defaults__
f.__kwdefaults__ = f_patch.__kwdefaults__
f.__globals__ = f_patch.__globals__   <<<<< crashes here with 
"AttributeError: readonly attribute"


f('a', e='e')


It seems like we need to work with the globals we have aka. importing 
things locally.


Best,
Sven