[Python-Dev] Guarantee ordered dict literals in v3.7?

[Paul Sokolovsky]

Hello,

On Tue, 7 Nov 2017 14:40:07 +0900
INADA Naoki <songofacandy at gmail.com> wrote:

> I agree with Raymond.  dict ordered by default makes better developer
> experience.
> 
> So, my concern is how "language spec" is important for minor (sorry
> about my bad vocabulary) implementation?
> What's difference between "MicroPython is 100% compatible with
> language spec" and
> "MicroPython is almost compatible with Python language spec, but has
> some restriction"?

So, the problem is that there's no "Python language spec". And over
time, that becomes a problem for alternative implementations, especially
not mainstream ("we have infinite amount of memory to burn") ones. What
we have is just CPython documentation, which mixes Python language spec
and CPython implementation details. And is being changed (including
"language spec" part) on the fiat of CPython developers, apparently
without any guarantees of platform stability and backward
compatibility.

Over time, this really becomes a visible drawback, comparing to the
close competitors. For example, year goes by year, but in JavaScript,

[] + []

is still:

''

That's stability!

[]

-- 
Best regards,
 Paul                          mailto:pmiscml at gmail.com