Antoine Pitrou added the comment: Does it still work? With both the C and Python pickler? Can you post an example? ---------- _______________________________________ Python tracker https://bugs.python.org/issue35933 _______________________________________

Change by Pierre Glaser : Removed file: https://bugs.python.org/file48111/test_slots.py _______________________________________ Python tracker https://bugs.python.org/issue35933 _______________________________________

Change by Pierre Glaser : Removed file: https://bugs.python.org/file48112/test_slots.py _______________________________________ Python tracker https://bugs.python.org/issue35933 _______________________________________

Antoine Pitrou added the comment: You can have both a dict and slots by subclassing:

...

...

class A: ...: __slots__ = ('x',) ...: class B(A): pass

b = B() b.x = 5 b.y = 6 b.__dict__ {'y': 6} A.x A.x.__get__(b) 5

---------- _______________________________________ Python tracker https://bugs.python.org/issue35933 _______________________________________

Pierre Glaser added the comment: Thanks Antoine and Raymond for the feedback. Indeed, a subclass of a slotted class can have a dict: I enriched the script, pickling_depickling instances of such subclasses, with the length-2 tuple __getstate__ method, and made sure their attributes were properly retrieved. Apart from the different checks on state carried out in the c load_build and the python load_build, AFAICT, it seems like this feature works :) ---------- _______________________________________ Python tracker https://bugs.python.org/issue35933 _______________________________________

Change by Pierre Glaser : Added file: https://bugs.python.org/file48114/test_slots.py _______________________________________ Python tracker https://bugs.python.org/issue35933 _______________________________________

Serhiy Storchaka added the comment: A slotted class will have a dict also when it inherits it from a non-slotted class. This is why the base class of slotted class should have slots if you do not want an instance dict. __getstate__ and __setstate__ for slotted classes are described in PEP 307. Unfortunately this was not copied to the module documentation. ---------- _______________________________________ Python tracker https://bugs.python.org/issue35933 _______________________________________

Serhiy Storchaka added the comment: See also issue26579 which propose to add a function or method for standard implementation of __getstate__ and use it consistently in custom __getstate__ implementations. I am not sure about API yet. ---------- _______________________________________ Python tracker https://bugs.python.org/issue35933 _______________________________________