On Thu, Jul 26, 2018 at 1:19 PM, David Mertz <me...@gnosis.cx> wrote: > On Wed, Jul 25, 2018 at 11:08 PM Chris Angelico <ros...@gmail.com> wrote: >> >> > Yeah, yeah. I know it's alpha software I wrote two nights ago, and >> > slightly >> > patched 5 minutes before that post. You fixed those concerns; I'll >> > happily >> > take PRs on fixing them better. >> >> PRs? Nope. I don't think it's possible to do this with correct >> semantics without language support. >> >> With PEP 505, I could write this: >> >> >>> print(spam?.nil?.nil?.nil?.nil) >> None >> >> Can you do that with your proxy? > > > Oh yeah. You are right! Thank you. > > That's a bug in my proxy too. I'll figure out how to fix it in 0.1.2 soon. > This is early alpha, and the things you're noting are valuable bug reports. > But none of this is fundamentally unfixable in a library, nor even > especially difficult.
If you're going to make that work, then by definition you would be wrapping up the None, right? Which would mean that every one of the prints would say "<NullCoalesce proxy for None>". Which, in turn, means that you cannot do this: >>> NullCoalesce(spam).nil is None or rather, it will always be False. With PEP 505, you most certainly *can* do this check, because it would really truly be None. This IS fundamentally unfixable in a library. ChrisA _______________________________________________ Python-ideas mailing list Python-ideas@python.org https://mail.python.org/mailman/listinfo/python-ideas Code of Conduct: http://python.org/psf/codeofconduct/
