On Wednesday, 15 May 2019 13.45.55 WEST Jean-Marc Lasgouttes wrote: > Le 15/05/2019 à 14:29, José Abílio Matos a écrit : > > On Tuesday, 14 May 2019 19.17.56 WEST Jean-Marc Lasgouttes wrote: > >> On my self-build master LyX on windows 10, I get the error below when > >> reconfiguring. Python is 3.6. > >> > >> What is that? > >> > >> JMarc > > > > Based on this I would like to suggest before 2.4 to modify the current > > python detection logic. > > You mean that I was a bit too brave when deciding to install only python3?
Nope. :-) As I have told you I had some of the fedora packages (from the equivalent of a ppa) running with python 3 only. Some of the python3 problems found later did not happen for me because I did not execute that code (like some converters and equivalent). > > Instead of using the first version we find, I would suggest to try first > > to > > detect python 3 and only then if it is not detected to search for python > > 2. > > Currently, we have a baroque list which is: > > [python python2 python3 python3.3 python3.2 python3.1 python3.0 > python2.7 dnl > python2.6 python2.5 python2.4 python2.3 python2.2 python2.1 python2.0]) > > Does it really correspond to some relevant ordering? What would you > suggest instead? Move "python2" just before python2.7? And put "poython" > at the end? Not only that but it is plainly wrong. We support python 2 but just for python 2.7. Our code to be compatible with python 3 requires python 2.7 at least. > I guess we can get rid of most of the pythonX.y values, or do they make > sense in any way? We should get rid of those and only test python2 and python3, not even just python. That comes from https://www.python.org/dev/peps/pep-0394/ (Note that this pep is originally from 2011 and so it should be implemented in all the systems that we support) First the convention: python2 will refer to some version of Python 2.x. python3 will refer to some version of Python 3.x. Notice that at the begin it recommends: * Unix-like software distributions (including systems like Mac OS X and Cygwin) should install the python2 command into the default path whenever a version of the Python 2 interpreter is installed, and the same for python3 and the Python 3 interpreter. * When invoked, python2 should run some version of the Python 2 interpreter, and python3 should run some version of the Python 3 interpreter. On my system I have: $ ls -l /usr/bin/python lrwxrwxrwx. 1 root root 7 Apr 30 16:55 /usr/bin/python -> python2 $ ls -l /usr/bin/python2 lrwxrwxrwx. 1 root root 9 Apr 30 16:55 /usr/bin/python2 -> python2.7 $ ls -l /usr/bin/python3 lrwxrwxrwx. 1 root root 9 May 11 01:41 /usr/bin/python3 -> python3.7 So all the systems that we support should have one of python2 or python3. > JMarc > > > The advantage of this approach is that it works for places that only have > > python 2 installed. > > But how is this related to the problem I had? I suspect that Jürgen has python3 installed. If when developing by default python3 was active Jürgen would catch this issue immediately and so no problem for you. > JMarc -- José Abílio
