On Mon, Jan 28, 2013 at 11:17 PM, Steven D'Aprano <st...@pearwood.info> wrote: > On 28/01/13 23:52, Antoine Pitrou wrote: >> >> Le Mon, 28 Jan 2013 22:31:29 +1000, >> Nick Coghlan<ncogh...@gmail.com> a écrit : >>> >>> >>>>> 6. Under "New collections" >>>>> >>>>> Why both lists and sets? >>>> >>>> >>>> Because pytz did it. But yes, you are right, an ordered set is a >>>> better solution. Baseing it on OrderedDict seems like a hack, >>>> though. I could implement a custom orderedset, of course. >>> >>> >>> Sets themselves have an honourable history of just being a thin >>> wrapper around dictionaries with all the values set to None (although >>> they're not implemented that way any more). Whether you create an >>> actual OrderedSet class, or just expose the result of calling keys() >>> on an OrderedDict instance is just an implementation detail, though. >> >> >> Why the complication? Just expose a regular set and let users call >> sorted() if that's what they want. > > > An OrderedSet is not a sorted set. > > An OrderedSet, like an OrderedDict, remembers *insertion order*, it does > not automatically sort the keys. So if datetime needs an ordered set, and > I have no opinion on whether or not it really does, calling sorted() on a > regular set is not the solution.
I think the use case for needing really quick checks if a string is in the list of recognized timezone is rather unusual. What is usually needed is a sorted list of valid time zone names. I'll drop the set. //Lennart _______________________________________________ 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
