[Python-ideas] Proposal: A Reduce-Map Comprehension and a "last" builtin

[Paul Moore]

On 11 April 2018 at 04:41, Steven D'Aprano <steve at pearwood.info> wrote:
>> > But in a way that more intuitively expresses the intent of the code, it
>> > would be great to have more options on the market.
>>
>> It's worth adding a reminder here that "having more options on the
>> market" is pretty directly in contradiction to the Zen of Python -
>> "There should be one-- and preferably only one --obvious way to do
>> it".
>
> I'm afraid I'm going to (mildly) object here. At least you didn't
> misquote the Zen as "Only One Way To Do It" :-)
>
> The Zen here is not a prohibition against there being multiple ways to
> do something -- how could it, given that Python is a general purpose
> programming language there is always going to be multiple ways to write
> any piece of code? Rather, it exhorts us to make sure that there are one
> or more ways to "do it", at least one of which is obvious.

I apologise if I came across as implying that I thought the Zen said
that having multiple ways was prohibited. I don't (and certainly the
Zen doesn't mean that). Rather, I was saying that using "it gives us
an additional way to do something" is a bad argument in favour of a
proposal for Python. At a minimum, the proposal needs to argue why the
new feature is "more obvious" than the existing ways (bonus points if
the proposer is Dutch - see the following Zen item ;-)), or why it
offers a capability that isn't possible with the existing language.
And I'm not even saying that the OP hasn't attempted to make such
arguments (even if I disagree with them). All I was pointing out was
that the comment "it would be great to have more options on the
market" implies a misunderstanding of the design goals of Python
(hence my "reminder" of the principle I think is relevant here).

Sorry again if that's not what it sounded like.
Paul