Collin Winter wrote:
Reusing the Pickler without clearing the memo will produce pickles that are, as best I can see, invalid
I'm not sure what you mean by "reusing the pickler" here, and how it can produce an invalid pickle. I think what the docs mean by it is continuing to pickle objects to the same file, but in a logically separate block that doesn't share any references with the previous one, e.g. pickle obj1 pickle obj2 ---clear memo--- pickle obj3 The whole thing is still a valid pickle containing 3 objects, whether the memo is cleared at any point or not, and can be unpickled using 3 corresponding unpickle calls to a single unpickler.
1) Should Pickler/Unpickler objects automatically clear their memos when dumping/loading?
If you mean should every call to Pickler.dump() or Unpickler.load() clear the memo first, definitely *NOT*. It's explicitly part of the specification that you can make multiple calls to dump() to build up a single pickle that shares state, as long as you unpickle it using a corresponding number of load() calls.
2) Is memo an intentionally exposed, supported part of the Pickler/Unpickler API, despite the lack of documentation and tests?
I think the 2.4 and later docs make it clear that it's no longer considered part of the public API, if it ever was. If seeding the memo is considered a legitimate need, an API could be provided for doing that. -- Greg _______________________________________________ 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
