On Sun, 18 Aug 2013 09:03:56 +0200 Armin Rigo <ar...@tunes.org> wrote: > Hi, > > On Sat, Aug 17, 2013 at 8:42 PM, Antoine Pitrou <solip...@pitrou.net> wrote: > >> summary: > >> Use a known unique object for the dummy entry. > > Another issue with this change: the dummy object should be of a dummy > subclass of 'object', rather than of 'object' itself. When it is > 'object' itself, a custom __eq__() method will be called, sending what > should be the dummy object to the pure Python code explicitly, as in > the example below. This is bad because ---in addition to calling > __eq__() with unexpected arguments, which might break some code--- we > could then take the dummy object, and try to insert it into another > set...
Indeed. Also, any non-trivial __eq__ will start receiving unexpected objects and may break in mysterious ways... Regards Antoine. _______________________________________________ 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
