On Fri, Feb 3, 2012 at 10:04 AM, Guido van Rossum <gu...@python.org> wrote: > On Thu, Feb 2, 2012 at 3:41 PM, Nick Coghlan <ncogh...@gmail.com> wrote: >> On Fri, Feb 3, 2012 at 9:32 AM, Yury Selivanov <yselivanov...@gmail.com> >> wrote: >>> In my opinion using Ellipsis is just wrong. It is completely >>> non-obvious not only to a beginner, but even to an experienced >>> python developer. Writing 'raise Something() from None' >>> looks less suspicious, but still strange. >> >> Beginners will never even see it (unless they're printing out >> __cause__ explicitly for some unknown reason). Experienced devs can go >> read language reference or PEP 409 for the rationale (that's one of >> the reasons we have a PEP process). > > I somehow have a feeling that Yury misread the PEP (or maybe my +1) as > saying that the syntax for suppressing the context would be "raise > <exception> from Ellipsis". That's not the case, it's "from None".
Oh right, that objection makes more sense. FWIW, I expect the implementation will *allow* "raise exc from Ellipsis" as an odd synonym for "raise exc". I'd want to allow "exc.__cause__ = Ellipsis" to reset an exception with a previously set __cause__ back to the default state, at which point the synonym follows from the semantics of "raise X from Y" as syntactic sugar for "_exc = X; _exc.__cause__ = Y; raise _exc" Cheers, Nick. -- Nick Coghlan | ncogh...@gmail.com | Brisbane, Australia _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
