[Python-Dev] Python 3.6 dict becomes compact and gets a private version; and keywords become ordered

[Antoine Pitrou]

On Thu, 8 Sep 2016 14:20:53 -0700
Victor Stinner <victor.stinner at gmail.com> wrote:
> 2016-09-08 13:36 GMT-07:00 Guido van Rossum <guido at python.org>:
> > IIUC there's one small thing we might still want to change somewhere
> > after 3.6b1 but before 3.6rc1: the order is not preserved when you
> > delete some keys and then add some other keys. Apparently PyPy has
> > come up with a clever solution for this, and we should probably adopt
> > it, but it's probably best not to hurry that for 3.6b1.  
> 
> Very good news: I was wrong, Raymond Hettinger confirmed that the
> Python 3.6 dict *already* preserves the items order in all cases. In
> short, Python 3.6 dict = Python 3.5 OrderedDict (in fact, OrderedDict
> has a few more methods).

Is it an official feature of the language or an implementation detail?

Regards

Antoine.