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Comment by JiNCMG | Hacker News Reader

MacOS (Certified Unix OS) is bundled with multiple OpenSource projects since it's initial OS X release, just like many other *nix OSes. It's so easy to install your own version and override it that this is not an issue. Simple response... use brew.

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PSA: don't use brew to manage your development python, unless you like having the carpet pulled out from under you by brew deciding to change 3.8 to 3.9 on you.

Use brew to install pyenv (or bootstrap it from github). Use pyenv to manage python versions, and then use a virtualenv.

Or conda, if that is your jam.

https://github.com/pyenv/pyenv

Yes, this is what I do now and since moving to pyenv I haven't had any real issues. The only glitch was that I have to upgrade pyenv from 2.2.3 to 2.2.4 and it just tells me 2.2.4 is already installed when I'm running 2.2.3. I'm guessing that's a homebrew thing?

Don’t use brew to manage your development anything. Carpet-pulling is pretty much intrinsic to its design.

“hey I upgraded openssl for you and trashed the old one, hope you hadn’t built anything against it!”

>It's so easy to install your own version and override it that this is not an issue.

It's easy to override it? Really? Don't forget that macOS comes with bash, zsh, ksh, tcsh... You have to override it in each of those!

You can easily set your $PATH so that your preferred tooling is first in the search order.

There's a bunch of places that can still get tripped up:

- scripts with `#!/usr/bin/python` instead of `#!/usr/bin/env python`

- shell scripts which call /usr/bin/python directly instead of the one in your path

- shell scripts which intentionally set a prefix in $PATH to some vendor directory with a custom python, but the vendoring is incomplete and leaky and it implicitly loads packages from your system python anyway

plus a hojillion other things I'm not thinking of...

GUI apps also have their own special $PATH set via launchctl.

But scripts calling /usr/bin/python want to use the "system" / "bundled" Python - why would you want those to run with your version of Python???

Because in 120% of situations, that "want" is actually "I had no clue how *nix works and just pasted in the result of `which python` in my system".

Do you think the same is true of #!/bin/bash? Why not?

macOS*

I don’t get your point. Are you agreeing?

you should absolutely avoid overriding the default python installation if you're on a distribution that ships python2 by default in particular, because that is a good way to kill a good chunk of your system.

Everyone should depend on “python3” or “python2”, never just “python”. They aren’t really the same language. python3 can’t run python2 scripts, nor vice versa, so no matter what you expected there will be systems on which you won’t get it.

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