On 12 April 2018 at 07:28, Chris Angelico <ros...@gmail.com> wrote: > On Thu, Apr 12, 2018 at 1:22 AM, Nick Coghlan <ncogh...@gmail.com> wrote: >>> Frequently Raised Objections >>> ============================ >> >> There needs to be a subsection here regarding the need to call `del` >> at class and module scope, just as there is for loop iteration >> variables at those scopes. > > Hmm, I'm not sure I follow. Are you saying that this is an objection > to assignment expressions, or an objection to them not being > statement-local? If the latter, it's really more about "rejected > alternative proposals".
It's both - accidentally polluting class and module namespaces is an argument against expression level assignments in general, and sublocal namespaces aimed to eliminate that downside. Since feedback on the earlier versions of the PEP has moved sublocal namespaces into the "rejected due to excessive conceptual complexity" box, that means accidental namespace pollution comes back as a downside that the PEP should mention. I don't think it needs to say much, just point out that they share the downside of regular for loops: if you use one at class or module scope, and don't want to export the name, you need to delete it explicitly. Cheers, Nick. -- Nick Coghlan | ncogh...@gmail.com | Brisbane, Australia _______________________________________________ Python-ideas mailing list Pythonfirstname.lastname@example.org https://mail.python.org/mailman/listinfo/python-ideas Code of Conduct: http://python.org/psf/codeofconduct/