[Nix-dev] Re: May I remove the old python code?

[Ludovic Courtès]

Hello,

Peter Simons <simons at cryp.to> writes:

> Hi Marc,
>
>  > Using PYHTONPATH is not enough because it doesn't make python read
>  > the .pth files telling python where to find additional modules.
>
> this statement doesn't seem to make sense. ${PYTHONPATH} is used to find
> the installed modules. When a module is listed in that variable, it *is*
> found. My understanding is that *.pth files are Python's native
> mechanism for computing the proper setting for ${PYTHONPATH}. If
> ${PYTHONPATH} is set correctly, however, the *.pth files aren't needed.
> Now, all the information we need is available in the Nix package
> description -- Nix *can* compute a proper ${PYTHONPATH}. The addition of
> ${NIX_PYTHON_SITES} feels unnecessary to me.

That's also my feeling.  In general, I would find it surprising that we
have to solve a path-related problem not already solved upstream.

> Besides, I am really not fond of the fact that the new Python expression
> contains the to-be-installed Python modules. That logic is wrong: Those
> modules ought to reference Python, not the other way round.

+1.

Ludo'.