On Fri, Sep 25, 2020 at 08:52:45PM -1000, David Mertz wrote: > On Fri, Sep 25, 2020, 5:49 PM Steven D'Aprano > > > Since both None and () are likely to be legitimate indexes, and > > NotImplemented is less likely to be such, I think this supports using > > NotImplemented. > > > > I think your arguments for NotImplemented vs None or () are solid. But I'm > having trouble crossing my eyes in just the way that will make those words > fit the purpose. > > What about instead subclassing NotImplemented as maybe NoIndex? That would > make sense in reading, and have the same favorable characteristics. > Moreover, being a brand new class, we can be certain no one is already > using it.
I don't object to this. If we added NoIndex, we could make it unhashable too. But I wouldn't want the PEP to rely on the Steering Council accepting a new builtin just for this. If the Steering Council will accept a new builtin, then I agree, this is a nice way of handling it and avoiding even the faintest possibility of collision with code that uses NotImplemented as a key. -- Steve _______________________________________________ Python-ideas mailing list -- python-ideas@python.org To unsubscribe send an email to python-ideas-le...@python.org https://mail.python.org/mailman3/lists/python-ideas.python.org/ Message archived at https://mail.python.org/archives/list/python-ideas@python.org/message/SBDZU57HGFEWJ3MV5UAMSS3QBX5JPOVS/ Code of Conduct: http://python.org/psf/codeofconduct/
