On Mon, Feb 19, 2018 at 07:02:42PM -0800, Guido van Rossum wrote: > On Mon, Feb 19, 2018 at 5:06 PM, Chris Barker - NOAA Federal < > chris.bar...@noaa.gov> wrote: [...] > > This seems another use case — maybe it would be helpful to be able to > > freeze an instance after creation for multiple use-cases? > > But how?
I haven't got all the details yet, but how badly do you hate the technique of swapping out __class__ to get a change in behaviour? https://www.safaribooksonline.com/library/view/python-cookbook/0596001673/ch05s19.html or https://code.activestate.com/recipes/68429-ring-buffer/ (I believe that in the Objective C community, something very close to this is called "swizzling".) So in principle, we could have a mutable class, and a immutable one, and when you flick the switch, the instance.__class__ changes from mutable to frozen. If you don't hate this, we can think about the details needed to get it work in practice. -- Steve _______________________________________________ Python-Dev mailing list Python-Dev@python.org https://mail.python.org/mailman/listinfo/python-dev Unsubscribe: https://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
