[StreakyCobra]

So to avoid re-opening the debate of Python 2 vs Python 3, let's take this point of view: The Python 3 language may, or may not, have been an improvement, and the transition from 2 to 3 may, or may not, have been done correctly. Everyone has its own opinion on this. But at the end this problem concerns the Python community.

From the Arch developers point of view, the Python developers decided to release a new version of their language. They were going to support python 2 for a while, but the direction that the language was taking for the future was Python 3, so one day or another Python 3 would become the standard, so doing the switch was the good decision.

As said by @tbranyen the work of adapting shebangs have been done on the Arch side anyway, so I don't see a problem for people developing their projects in Python. Also Arch users are mostly power users (you need to understand quite a bit about linux to install it) so they are usually able to handle python 2 vs 3 errors quite well, especially as it is known than Arch use Python 3 by default.

[bbatha]

Except that python says that python 3 should be an executable named `python3` and `python` should refer to `python2` [0]

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

[jvreeland]

It says right in the pep

"...however, end users should be aware that python refers to python3 on at least Arch Linux (that change is what prompted the creation of this PEP), so python should be used in the shebang line only for scripts that are source compatible with both Python 2 and 3..."

There was no guidance before the Arch devs made their choice. There's no reason to change back.

Especially since the goal is that python3 will be default eventually.

"...in preparation for an eventual change in the default version of Python, Python 2 only scripts should either be updated to be source compatible with Python 3 or else to use python2 in the shebang line."

[srssays]

There's a good reason to change back. There is now convention in place, and Arch's approach is obsolete.

[lelandbatey]

It seems to me that Arch established their convention first, so why should Arch "change back" when they where first; why are others not "changing back" to Arch's convention, given that Arch's came first?

Well, the answer is that this is a silly discussion. Arch is doing what Arch is doing because Arch is intentionally forward oriented, sometimes to the detriment of backwards compatibility with the old school (and yes, a distro not having a symlink for python2 is at this point nearly 5 years into being "old school").

[srssays]

A particular convention has been adopted by nearly all distros, the Python project and the Python community. That convention is better than Arch's, because it is backwards-compatible with the large body of Python 2 code that exists.

Arch's change angered many in the Python community, and broke a lot of code. That Arch refuse to adopt the established convention, because it would involve admitting a mistake, shows a distinct lack of professionalism.

[StreakyCobra]

I don't understand why people always want to tell other people how to behave. The change was decided by Arch developers and impacted only the Arch distribution. Arch developers and Arch users did their job by adapting the Arch packages to work with this. I don't see any problem. If users don't like this choice, they are free to use any other distribution. If software developer don't like this choice, they are also free to not support Arch. And even this is not a problem most of the time because Arch users are doing the effort of adapting and packaging applications themselves on AUR.

[StreakyCobra]

Fair point. But Archlinux made the switch in 2010 [1], and this PEP was created in 2011.

[1] https://www.archlinux.org/news/python-is-now-python-3/

[blipmusic]

Using the official, graphical installer for Python 3 on Windows with no previous version installed creates an executable 'python' that refers to Python 3.

(Normally not a Windows user so I have no idea why this is the case or if by design.)

[groovy2shoes]

Windows doesn't support shebang lines, so the exact name/location of the interpreter doesn't matter as much as it does on 'nix.

[maxerickson]

Recent versions of python ship with a launcher shim for windows that does support the shebang line (to simplify using multiple interpreters):

https://www.python.org/dev/peps/pep-0397/

As you say though, it doesn't rely on the names of the exes.

[CJefferson]

I work on two programs which either not distributed by Arch, or our users choose to download directly (I don't know).

They both contained Python scripts, and I had to waste my time figuring out why they had broken when I had e-mails from Arch users complaining they didn't work -- and then keep replying to future Arch users with the fix.

I don't know how many hours and days of other developer's time was wasted by Arch with this change, but it certainly wasted a good day of my time over the last few years.