[Python-ideas] Should Python have user-defined constants?

[Stéfane Fermigier]

That's one way to do it with no changes to the language, though
syntaxically I find it lacking a bit of elegance (maybe a matter of getting
accustomed with it?).

Also, I'm not sure "Final" really conveys what it means (at first glance, I
thought it was about immutability, not constantness).

Maybe "Const" would be better in this context ? (Or maybe you've discussed
this question already and come to the conclusion that "Final" is better for
some reason?)

  S.


On Tue, Nov 21, 2017 at 11:41 AM, Ivan Levkivskyi <levkivskyi at gmail.com>
wrote:

> On 21 November 2017 at 10:47, Paul Moore <p.f.moore at gmail.com> wrote:
>
>> -1. I don't see how this would improve any programs I've written or
>> seen. Tools like mypy or linters might benefit from a feature to track
>> constants and ensure they don't get changed
>>
>
> It is actually likely that something like this will appear in ``typing``:
>
>     from typing import Final, List
>
>     x: Final = 42
>     x = 1  # Fails type check
>
>     lst: Final[List[int]] = []
>     lst.append(5)  # OK
>     lst = [1, 2, 3]  # Fails type check
>
> --
> Ivan
>
>
>
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---
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