[Python-Dev] RFC: PEP 509: Add a private version to dict

[Victor Stinner]

Hi,

FYI I updated the implementation of the PEP 509:
https://bugs.python.org/issue26058


2016-04-15 11:01 GMT+02:00 Antoine Pitrou <antoine at python.org>:
> Why do this? It's a nice property that two dicts always have different
> version tags, and now you're killing this property for... no obvious
> reason?
>
> Do you really think dict.clear() is in need of micro-optimizing a
> couple CPU cycles away?

So, I played with Armin's idea. I confirm that it works for my use
case, guards on dict keys. It should also work on Yury's use case.

Antoine is right, it's really a micro-optimization. It shouldn't help
much for the integer overflow (which is not a real issue in practice).

I propose to leave the PEP unchanged to keep the nice property of
unique identifier for empty dictionaries. It can help for future use
cases.

Victor