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by maweki 1688 days ago
PEP 394 (which is now superseeded) clearly states that "python" shall invoke python2 and not python3

https://www.python.org/dev/peps/pep-0394/

"The python command should always invoke Python 2 (to prevent hard-to-diagnose errors when Python 2 code is run on Python 3)."

So there was indeed a time where the mentioned scenario was possible.

Edit: love those people who got to downvote reality. At no point was python pointing to either 2 or 3 will-nilly, but there was always a PEP specifying best practice behaviour.
2 comments
eesmith 1688 days ago
> "python" shall invoke python2 and not python3

The current version of PEP 394 says:

] If the python command is installed, it is expected to invoke either the same version of Python as the python3 command or as the python2 command.

] Distributors may choose to set the behavior of the python command as follows:

    python2,
    python3,
    not provide python command,
    allow python to be configurable by an end user or a system administrator.
The part you quoted is from the section "History of this PEP". Just before your quoted text is:

] This PEP originally provided a very simple mechanism ...

and just after it is:

] However, these recommendations implicitly assumed that Python 2 would always be available.

This historic advice is no longer recommended.

The change was made on July 5, 2019 - https://github.com/python/peps/commit/ae932bd6fd2c493d7d64ce... .

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remram 1688 days ago
The PEP is not superseded, still active. You got this quote from the "history of this PEP" section. This is not what the PEP currently mandates and it hasn't for 2.5 years: https://github.com/python/peps/pull/989
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maweki 1688 days ago
That was not the point. There was a time where the PEP specified that "python" means "python2" and it was indeed possible to have no "python" but still a Python (3) installation.
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