[Larry Hastings <la...@hastings.org>] > As of 3.7, dict objects are guaranteed to maintain insertion order. But set > objects make no such guarantee, and AFAIK in practice they don't maintain > insertion order either.
If they ever appear to, it's an accident you shouldn't rely on. > Should they? >From Raymond, 22 Dec 2017: https://twitter.com/raymondh/status/944454031870607360 """ Sets use a different algorithm that isn't as amendable to retaining insertion order. Set-to-set operations lose their flexibility and optimizations if order is required. Set mathematics are defined in terms of unordered sets. In short, set ordering isn't in the immediate future. """ Which is more an answer to "will they?" than "should they?" ;-) _______________________________________________ Python-Dev mailing list -- python-dev@python.org To unsubscribe send an email to python-dev-le...@python.org https://mail.python.org/mailman3/lists/python-dev.python.org/ Message archived at https://mail.python.org/archives/list/python-dev@python.org/message/WMIZRFJZXI3CD5YMLOC5Z3LXVXD7HM4R/ Code of Conduct: http://python.org/psf/codeofconduct/
