[Pyobjc-dev] NSCoding support for python list & dict

[Barry W. <bar...@gm...>]

PyObjC2 now raises an exception if one tries to encode a python list
or dict instance using an NSCoder. I agree that this behavior is
preferable to letting the action proceed silently. I'm wondering why
PyObjC doesn't encode a list as if it were an NSMutableArray and a
dict as if it were an NSMutableDictionary, however. One of our apps
does a lot encoding of dictionaries created in python plugins.
Converting these dicts to NSDictionaries via
NSDictionary.dictionaryFromDictionary_ is fine, but seems to be a
glaring special case of the otherwise seemless bridge. If I can treat
python dicts as NSMutableDictionaries on the Objective-C side, why
can't I encode them as such? Scanning the NEWS file, I see that this
is mentioned, but I haven't found the rationale.

Please understand I'm not trying to disparage the amazing work that
the PyObjC devs have done on PyObjC2. I'm just posing the question to
either understand the technical reason(s) behind the decision or raise
some discussion on other options.

Thanks,
Barry