Multiple versions of Python coexisting in the same OS

[Gelonida]

Hi Edward,

On 07/25/2010 04:40 AM, Edward Diener wrote:

> I found the solutions too exotic for actual use, and completely
> ineffectual for the cases I originally cited. The people in that thread
> seem to have completely forgotten that Python can be invoked externally
> and internally both through executing 'python(w) xxx' and through
> executing a file with the file extension(s) associated with Python. They
> seem to have forgotten this can be within scripts or any other program
> using Python, both written by themselves and by others, and not just by
> their typing 'python(w) xxx' somewhere. Their solutions seem to believe
> that only they will externally be i9nvoking Python and only for their
> own written scripts, as opposed to the many libraries using Python as
> well as the Python distribution itself.
> 
> The best solution is some program which changes the PATH and the Python
> file type associations depending on which version of Python one wants to
> use on one's own system when more than one Python version must coexist
> with others. I will probably write such a program for myself.
> 
Hi Edward,

changing the path and is perfect for people who use consoles.
(under linux there's virtuelenv for his and it's great)

changing the file association is perfect for people who'd know at which
time they want to use which version of python.

The usecase, that I'm nore aware of however is somethig like having some
scripts / directories, that should use one version of python
and others that shoud use another.
In unix you do this normally with the 'shebang line'
( e.g.  #!/usr/bin/env/python2.6 )

There the windows solution could be something like a small 'pystarter'
program, which would decide depending on the file's location / the
file's first line which python should be started.