Re: Python 3

[Knut Petersen]

On 08.08.19 15:43, Gwyn Ciesla wrote:
> Python 2 EOL is in January. I've done a lot of Python 2->3 porting, let me know 
> if I can assist.

There are valid reasons not to use Guile 2.x., but there is, besides the lack 
of developers, no reason not to even try to convert the Lilypond sources to 
Python 3.

In Lilypond we have about 30,000 lines of Python code, plus about 20,000 lines 
in GuB.

Let's forget GUB for now. If we want to use Python 3 in GUB, the Lilypond 
sources have to be ported to Python 3 anyway.

I just created a new branch dev/knupero/lilypy3devel.

All *.py files were treated with 2to3, the used script and log were committed.

Also aclocal.m4 and configure.ac have been modified to require Python 3.7..3.99 
and to use 'print()' and not 'print' in Python code generated on-the-fly.

Some more changes can be found in the log.

After all, the changes are far-reaching enough for ./autogen.sh and ./configure 
to run successfully with Python 3.7. This is a starting point.

Nothing else works, and that's no wonder, after all there are enough hints in 
the log about places in the Python code that have to be adapted manually to 
Python 3.

I don't really know Python, even though I'm stubborn enough to eliminate 
anachronisms and errors in other programmers' code from time to time. Everybody 
is therefore cordially invited to cooperate.

Knut