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

[Mark Lawrence]

On 12/09/2016 23:25, Gregory P. Smith wrote:
> On Mon, Sep 12, 2016 at 10:25 AM INADA Naoki wrote:
>
>
>     So fundamental question is: Is it to so bad thing that some people
>     write code depending on CPython and PyPy implementation?
>
>
> Yes.  See below.
>
>     I think cross-interpreter libraries can use OrederedDict correctly
>     when they should use it. (They may run test on micropython, Jython
>     and IronPython).
>
>
> The problem is that libraries which could otherwise be cross-VM
> compatible are not because they depend upon an implementation detail. So
> it becomes an additional porting burden on people trying to use the
> library on another VM that could've been avoided if we required people
> to be explicit about their needs.
>
> BUT...
>
> At this point I think coding up an example patch against beta1 offering
> a choice of disordered iteration capability that does not increase
> memory or iteration overhead in any significant way is needed.
>
> The problem is... I don't know how to express this as an API. Which
> sinks my whole though process and tables the idea.
>

"tables the idea"  has the US meaning of close it down, not the UK 
meaning of open it up? :)

-- 
My fellow Pythonistas, ask not what our language can do for you, ask
what you can do for our language.

Mark Lawrence