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0 pointsjsmeaton6y ago0 comments

Pyenv is for installing multiple versions of python. Virtualenvs are a layer beneath that.

It’s super useful for maintaining static versions of python, like 2.7, 3.6 and 3.7 when you have many projects that have different python requirements.

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japhyr6y ago

I understand how this was needed historically, when using the official installer might overwrite the Python you already had installed. But as far as I know, you can download an installer for a new version, run it, and it doesn't touch your previous installation.

For example I've had 3.7 on my macOS system for a while, installed from the official installer, not through Homebrew. I just installed 3.8, which pointed my python3 to 3.8. But my 3.7 was still there; I created an alias python3.7 to point to that. So I can run or install anything I want against 3.7 or 3.8.

Why do we still need pyenv? I'm not asking that antagonistically, I really don't understand at this point and I'm wondering if I'm missing something.

philwelch6y ago

Sometimes scripts will want to invoke Python as ‘python’ and it’s easier to use pyenv to set $PATH overrides.

japhyr6y ago

Thank you, that’s the first concrete reason I’ve heard. It also explains why I haven’t run into issues yet using my own aliases.

heavenlyblue6y ago

Why do you need pyenv to set PATH?

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jsmeatonOP6y ago

Honestly I haven’t used official installations before so I can’t speak to that too much. Pyenv mostly uses official builds though so it’s mostly an automated frontend to manual installs.

I like being able to specify the global and local versions for my projects and the system as a whole. I also use it as a virtualenv manager. It works well with pipenv (which I still use in anger) and vscode.

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japhyr6y ago

Why do we still need pyenv? I'm not asking that antagonistically, I really don't understand at this point and I'm wondering if I'm missing something.

philwelch6y ago

Sometimes scripts will want to invoke Python as ‘python’ and it’s easier to use pyenv to set $PATH overrides.

japhyr6y ago

Thank you, that’s the first concrete reason I’ve heard. It also explains why I haven’t run into issues yet using my own aliases.

heavenlyblue6y ago

Why do you need pyenv to set PATH?

1 more reply

jsmeatonOP6y ago

Honestly I haven’t used official installations before so I can’t speak to that too much. Pyenv mostly uses official builds though so it’s mostly an automated frontend to manual installs.

j / k navigate · click thread line to collapse