[GRASS-dev] Handling of Python scripts on MS Windows

[Markus Metz]

Trying a summary on this discussion.

AFAIU, the whole discussion boils down to the question if we want to
require a system-wide installation of Python with correct python file
associations in the registry, potentially deactivating an existing
Python installation, or not.

There seems to be agreement that we do not want to modify any existing
system-wide python installation.

That means that WinGRASS should
1) not do a system-wide installation of Python
2) not require a system-wide Python installation
3) explicitly ignore any existing system-wide installation of Python,
or any Python file associations in the registry (text-editor,
whatever)

That means that we must assume that Windows has no idea what to do
with Python files, and if it has an idea, this is most probably a bad
idea, as far as GRASS scripts are concerned. As for shell scripts in
GRASS 6. That in turn means that GRASS Python scripts must be called
explicitly with GRASS_PYTHON, most importantly scripts from within
scripts.

IMHO, creating .bat files for python scripts is easy because the
equivalent is already working for WinGRASS 6.4 where .bat files are
created for shell scripts. AFAICT none of the other suggestions
(virtualenv, Python launcher, pip, etc) has been tested successfully
on Windows with GRASS 7, both with and without a separate incompatible
system-wide Python installation.

Markus M