And how would you implement that without support from the compiler? Does it use a hook that catches the NameError?
On Wed, Jun 29, 2016 at 11:15 AM, Brett Cannon <br...@python.org> wrote: > > > On Wed, 29 Jun 2016 at 10:41 Ethan Furman <et...@stoneleaf.us> wrote: >> >> There is a several-month-old request to add aenum's [1] AutoNumberEnum >> to the stdlib [2]. >> >> The requester and two of the three developers of Enum are in favor (the >> third hasn't chimed in yet). >> >> This new addition would enable the following: >> >> from Enum import AutoNumberEnum >> >> class Color(AutoNumberEnum): >> # auto-number magic is on >> Red >> Green >> Blue >> Cyan >> # magic turns off when non-enum is defined >> >> def is_primary(self): >> # typos in methods, etc, will raise >> return self in (self.Red, self.Grene, self.Blue) >> >> # typos after the initial definition stanza will raise >> BlueGreen = Blue + Grene >> >> There is, of course, the risk of typos during the initial member >> definition stanza, but since this magic only happens when the user >> explicitly asks for it (AutoNumberEnum), I think it is acceptable. >> >> The `start` parameter is still available, and assigning a number is >> supported (subsequent numbers will (re)start from the assigned number). >> >> Thoughts? Opinions? Flames? > > > Is it going to subclass Enum or IntEnum? Personally I would be quite happy > to never have to specify a value for enums ever again, but only if they > subclass Enum (since IntEnum is for compatibility with C stuff where a > specific value is needed I don't think users need to mess that up by having > the automatic numbering not work how they would expect). > > _______________________________________________ > Python-Dev mailing list > Python-Dev@python.org > https://mail.python.org/mailman/listinfo/python-dev > Unsubscribe: > https://mail.python.org/mailman/options/python-dev/guido%40python.org > -- --Guido van Rossum (python.org/~guido) _______________________________________________ Python-Dev mailing list Python-Dev@python.org https://mail.python.org/mailman/listinfo/python-dev Unsubscribe: https://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
