On 2012-06-18, at 9:36 PM, Nick Coghlan wrote: > On Tue, Jun 19, 2012 at 4:09 AM, Yury Selivanov <yselivanov...@gmail.com> > wrote: >> On 2012-06-18, at 1:35 PM, PJ Eby wrote: >>> Then just copy the signature itself; as currently written, this is going to >>> copy the annotation objects, which could produce weird side-effects from >>> introspection. Using deepcopy seems like overkill when all that's needed >>> is a new Signature instance with a fresh OrderedDict. >> >> That's an excerpt from Signature.__deepcopy__: >> >> cls = type(self) >> sig = cls.__new__(cls) >> sig.parameters = OrderedDict((name, param.__copy__()) \ >> for name, param in self.parameters.items()) >> >> And Parameter.__copy__: >> >> cls = type(self) >> copy = cls.__new__(cls) >> copy.__dict__.update(self.__dict__) >> return copy >> >> So we don't recursively deepcopy parameters in Signature.__deepcopy__ >> (I hope that we don't violate the deepcopy meaning here) > > In my opinion, It's better to redefine what you mean by a shallow copy > (making it a bit deeper than just the direct attributes) rather than > making a so-called deep copy shallower.
Agree. That's the only thing about the implementation that I really didn't like - deepcopy that's not exactly deep. > So keep the current copying semantics for Signature objects (i.e. > creating new copies of the Parameter objects as well), but call it a > shallow copy rather than a deep copy. Make it clear in the > documentation that any defaults and annotations are still shared with > the underlying callable. So, 'Signature.__deepcopy__()' -> 'Signature.shallow_copy()'? Or make it private - 'Signature._shallow_copy()'? - Yury _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
