On Tue, Nov 29, 2022 at 08:51:09PM -0000, Yoni Lavi wrote:
It does make your argument invalid though, since it's based on this assumption that I was asking for a requirement on iteration order (e.g. like dict's iteration order = insertion order guarantee), which is not the case.
Yoni, I think this answer is disingenious. Over on the Discuss threads, you have made it clear that the primary reason why you want hash(None) to return a constant value is so that set iteration order will be consistent from one run to another. Sure, you may *also* have some philosophical preference for None having a fixed hash, but you have barely mentioned that the same applies to Ellipsis and NotImplemented (and then only in passing), and that's not your driving motivation for this proposal. Let's consider a thought-experiment: suppose we agree to your proposal to make hash(None) return a constant, but at the same time modify the set iteration algorithm so that it starts from a different position each time you iterate, making set iteration order even more unpredictable and deterministically chaotic than it is now. Would that satisfy you? From your posts on Discuss, I don't expect that you will be happy with this outcome. Personally, and I don't expect that this will be a popular opinion, I wish that data structures that don't guarantee their iteration order would actively mix up their iteration order so that people wouldn't be tempted to rely on whatever accidental order they happen to get. Sure, it would cost a little bit of code to implement, but think of the savings in unproductive arguments and discussions like this one :-( It would also break the invariant that `repr(data) == repr(data)` but it is times like this that I feel that it would be worth it. -- Steve