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Comment by xdfgh1112 | Hacker News Reader

Have you used them? Perl has version tags in source code and everything is feature gated including the stdlib. Python does none of that. The stdlib changes constantly and just looking at source code gives you no indication if you can run it with your installed python version.

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> Perl has version tags in source code and everything is feature gated including the stdlib. Python does none of that.

  from __future__ import annotations

> just looking at source code gives you no indication if you can run it with your installed python version

  requires-python = ">=3.9"

I don't believe that "from __future__" is the future-proofing you think it is, they just named it that way to be cute - a hypothetical 3.19 version couldn't even use it, since it's just a normal python import

  $ python3.13 -c 'from __future__ import awesome_feature'
    File "<string>", line 1
  SyntaxError: future feature awesome_feature is not defined

the very idea of "future feature is not defined" is insaneo

Anyway, I'd guess what they intend is

  try:
    from __future__ import fever_dream
  except SyntaxError:
    fever_dream = None

because python really gets off on conditional imports

I was responding to the "Python does none of that" by pointing out that Python does indeed have features to help introduce new capabilities in a thoughtful way - I know it's not the same thing as something like conditional imports.

I prefer Perl's approach for both:

    use v5.40;

    ....

That's explicit, tied to a specific version, and executable code which can be scoped to a single source file.

(I'd argued for that feature for years with my `Modern::Perl` feature bundle; glad to see that can be deprecated now.)

Not sure that >= is going to age well.

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