[Reposting for the Gmane newsgroup] [Quoting out of order]

P.S. This list may not have enough subscribers yet to have a good discussion, so I'll post another thread about advertising, and then we can reboot this thread later if needed.

Agreed. On Oct 07, 2015, at 01:28 PM, Nick Coghlan wrote:

What do folks think of the idea of introducing a "Python Launcher for *nix" using the following iterative development model:

1. We update the Python 3 *nix builds to provide a "py" symlink by default. This would be the baseline state for Python 3.6 if the next step isn't completed in time.

2. The symlink is replaced with a custom launcher that works like the Python 3.5 version of the Windows launcher:

* accepts "-3", "-2", etc command line arguments like the Windows launcher * checks for an active virtualenv, if it finds one, uses the venv's default Python * checks for a user specific config file * checks for a global config file

I like it, although I would also like to support major.minor specifications. For example, in Ubuntu 15.10 we'll have two supported Python 3 versions, 3.4 and 3.5. We do have /usr/bin/python3 pointing to the default version, i.e. /usr/bin/python3.4 and that changes as we roll over to the new default version (it'll be 3.5 only for the next LTS). So `py -3` is unambiguous but folks might want to use `py -3.4` which kind of looks ugly. Maybe the launcher should take an optional mutually exclusive argument such as -i/--interpreter which would either give a shorthand, like 3.4 or a full path to the interpreter to choose. That would let people install say 3.6 in /usr/local and then they could `py -i /usr/local/bin/python3.6` (Is that a win over just using /usr/local/bin/python3.6? Not really, but I can see the launcher being scriptable so you'd want to allow such scripts to substitute the exact interpreter they want to use. OTOH YAGNI.) Cheers, -Barry