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Author realead
Recipients congma, mark.dickinson, miss-islington, realead, rhettinger, serhiy.storchaka, tim.peters
Date 2021-06-13.20:31:33
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Marked as misclassified Yes
Message-id <>

> expectation was that there would be few cases of breakage, and that for those few cases it shouldn't be difficult to fix the breakage.

This expectation is probably correct.

My issue is somewhat only partly on-topic here: If one wants to have all NaNs in one equivalency class (e.g. if used as a key-value for example in pandas) it is almost impossible to do so in a consistent way without taking a performance hit. It seems to be possible builtin-types (even if frozenset won't be pretty), but already something like

class A:
    def __init__(self, a):
    def __hash__(self):
        return hash(self.a)
    def __eq__(self, other):
        return self.a == other.a

is not easy to handle.

A special comparator for containers would be an ultimative solution, but I see how this could be too much hassle for a corner case.
Date User Action Args
2021-06-13 20:31:33realeadsetrecipients: + realead, tim.peters, rhettinger, mark.dickinson, serhiy.storchaka, miss-islington, congma
2021-06-13 20:31:33realeadsetmessageid: <>
2021-06-13 20:31:33realeadlinkissue43475 messages
2021-06-13 20:31:33realeadcreate