Terry J. Reedy <tjre...@udel.edu> added the comment: Given that equality is not identify, order does matter, although in 3.2.2 the results are the opposite of what one might expect.
a = set((1,2,3)) b = set((1.0, 3.0, 5.0)) print(a&b, b&a) print(a.intersection(b), b.intersection(a)) a &= b print(a) >>> {1.0, 3.0} {1, 3} {1.0, 3.0} {1, 3} {1.0, 3.0} In my view, a &= b should remove the members of a that are not in b, rather than deleting all and replacing some with equal members of b. That glitch aside, & remains and remains binary for exact control of order. The doc should just say that intersection may re-order the intersection for efficiency. ---------- nosy: +terry.reedy _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue13653> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com