[Python-Dev] PEP 572: A backward step in readability

[Paul Moore]

On 30 April 2018 at 17:37, Steven D'Aprano <steve at pearwood.info> wrote:
> On Mon, Apr 30, 2018 at 08:09:35AM +0100, Paddy McCarthy wrote:
> [...]
>> A PEP that can detract from readability; *readability*, a central
>> tenet of Python, should
>> be rejected, (on principle!), when such objections are treated so dismissively.
>
> Unless you have an objective measurement of readability, that objection
> is mere subjective personal preference, and not one that everyone agrees
> with. I for one think that used wisely, binding expressions will be
> *more* readable than the alternatives. (Even though := is not my
> preferred syntax.)

On the other hand, the PEP doesn't do much to address the various
claims of readability issues. Whether they are subjective or not,
well-founded or not, the PEP does (in my view) come across as
unnecessarily dismissive of the question of readability. I suspect
that's largely due to Chris being extremely tired of having the same
arguments over and over again, and I can understand that. However, I
think it could be covered more completely - the remainder of your post
is exactly the sort of response that would be useful to have recorded.

But one way or another, I think people will vote on the PEP based on
their (subjective) views, and so readability will get factored into
the overall response, one way or another. To what extent that response
affects Guido's final decision (I can't see him delegating on this
one!) remains to be seen, and honestly, I'm willing to trust Guido's
intuition.

Paul