[Python-ideas] Re: About python3 on windows

On 25 Mar 2020, at 09:15, Eryk Sun wrote:

On 3/25/20, Steve Barnes wrote:

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Except it's not necessarily what the original post wants. The OP wants the shebang "#!/usr/bin/env python3" to "work everywhere by default", for which I assume it's implied that it should work consistently everywhere. I'd prefer for the launcher's env search to also support versioned "pythonX[.Y][-32|-64]" commands such as "python3".

The windows launcher already does support this with shebangs of: #!/usr/bin/env python3 # Launch with the latest/preferred version of python3 #!/usr/bin/env python2 # Launch with the latest/preferred version of python2

That is not consistent with Unix. env is supposed to search PATH for the command. However, the launcher does not search PATH for a versioned command such as "python3". Instead it uses the highest version that's registered for 3.x or 2.x, respectively, or the version set by PY_PYTHON3 or PY_PYTHON2 if defined, respectively.

I think the reasoning is that the whole point of the py.exe is to avoid having users edit their PATH on Windows. And further the thinking goes that you do not need the alternatively named python programs. Is that your understanding as well Eryk? Barry

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#!/usr/bin/env python # Launch with the latest/preferred version of python 2 unless PY_PYTHON=3[.n[-64/32]] is set or py.ini has the same in.

In this case "env" first searches PATH before falling back on registered installations and PY_PYTHON, which is correct -- at least for the PATH search. I would prefer that "env" never checks registered installations. For the registry fallback, it should instead check the user and system "App Paths" key, like what ShellExecuteExW does. _______________________________________________ Python-ideas mailing list -- python-ideas@python.org To unsubscribe send an email to python-ideas-leave@python.org https://mail.python.org/mailman3/lists/python-ideas.python.org/ Message archived at https://mail.python.org/archives/list/python-ideas@python.org/message/YX4DOI... Code of Conduct: http://python.org/psf/codeofconduct/