type function does not subtype
Greg Ewing (using news.cis.dfn.de)
me at privacy.net
Wed Mar 26 00:07:10 CET 2003
Lenard Lindstrom wrote:
> As for uses, should not staticmethod and classmethod be subtypes
> of function? If one wants a function wrapper that looks like a function,
> e.g. has func_doc, func_code, and func_defaults members,
Staticmethods and classmethods don't have all those attributes,
so they shouldn't be subclasses of function.
> should not that wrapper class be derived from function?
Yes, but it will only have those attributes if it's a
subtype of "function consisting of interpreted Python
bytecode", not "callable object in general". The use
cases of *that* are somewhat more restricted.
That's not to say they don't exist, and I agree that
there's no reason for function objects *not* to be
subclassable. It's just that nobody's had a pressing
enough need to subclass one yet to make it so.
Greg Ewing, Computer Science Dept,
University of Canterbury,
Christchurch, New Zealand
More information about the Python-list