varargs in lambda functions in Python
There is no problem using varargs in lambda functions. The issue here is different:
The problem is that the the lambda refrences the loop variable v. But by the time the lambda is called, the value of v has changed and the lambda calls the wrong function. This is always something to watch out for when you define a lambda in a loop.
You can fix this by creating an additional function which will hold the value of v in a closure:
def create_not_function(v): return lambda s, *args, **kw: not v(s, *args, **kw)for (k, v) in _dict.items(): if hasattr(v, '__call__'): extended_dict["not_" + k] = create_not_function(v)