On Sat, Feb 6, 2021 at 8:54 PM Paul Sokolovsky <pmis...@gmail.com> wrote: > > Hello, > > On Sat, 6 Feb 2021 17:26:00 +1100 > Chris Angelico <ros...@gmail.com> wrote: > > > On Sat, Feb 6, 2021 at 5:21 PM Random832 <random...@fastmail.com> > > wrote: > > > > > > While we're on the subject of assignment expression limitations, > > > I've occasionally wanted to write something like > > > > > > try: > > > return a_dict[key] > > > except KeyError: > > > return (a_dict[key] := expression to construct value) > > > > That's what the __missing__ method is for. > > That's true, but that would be an argument against PEP572 ;-).
PEP 572 was never meant to replace all other ways of doing things, and __missing__ is exactly the tool for this job :) > But we live in a world where PEP572 is a reality, and people start to > look how to get the most juice out of it. Why? Just because it's there? > While triaging the issue with parallel assignments, I saw there's > already pretty long trail of elaboration of ":=" for various cases where > original implementation forced parens, which were looking weird to > human eye, e.g.: > > https://bugs.python.org/issue42316 > https://bugs.python.org/issue42374 > https://bugs.python.org/issue42381 > > My proposal is to file parallel assignment case into the same "inital > omission" department like the above. And just like the above, it seems > it would be a trivial grammar fix (I didn't run the whole testsuite on > the result yet though ;-) ). The omission was intentional, and so far, I'm not seeing a justification for reversing that decision :) ChrisA _______________________________________________ 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/UJ2GKZUS7FBYR3KDWCLC6ENVHSWGW6XZ/ Code of Conduct: http://python.org/psf/codeofconduct/
