From mboxrd@z Thu Jan  1 00:00:00 1970
From: Hartmut Goebel <h.goebel@crazy-compilers.com>
Subject: Re: Anomalies in Python search-path
Date: Mon, 16 Jan 2017 10:30:59 +0100
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To: =?UTF-8?Q?Ludovic_Court=c3=a8s?= <ludo@gnu.org>, Maxim Cournoyer <maxim.cournoyer@gmail.com>
Cc: guix-devel@gnu.org

Am 15.01.2017 um 23:10 schrieb Ludovic Court=C3=A8s:
>> > My last reporting that pip was working correctly in non-environment =
was
>> > wrong because I had failed to logout/login after installing the pyth=
on
>> > package; after doing so, the behavior is the same as in an environme=
nt:
>> > the user site location (~/.local/...) comes after site-packages rath=
er
>> > than before, as would normally be the case. Apparently this is due t=
o
>> > setting a site-packages location with the environment variable
>> > PYTHONPATH, which has precedence over the user site location.
> ~/.guix-profile/etc/profile prepends things to the search paths, but
> it=E2=80=99s up to the user whether to source it before or after other
> definitions have been provided (in .bash_profile or similar).

Maxim is talking about how python is processing the paths.

The "normal" order is:
- $PYTHONPATH  (which normaly does not include site-packages)
- Python Standard library (not including site-packages)
- user's site-packages (~/.local/lib/python3.4/site-packages)
- global site-packages (/usr/lib/python3.4/site-packages)

The user's site-packages take precedence over the global ones.

In Guix we currently use PYTHONPATH to add global site-packages. Since
PYTHONPATH parts are put in front of the search list, they take
precedence over the user's site-packages. And this behaviour is wrong.

--=20
Regards
Hartmut Goebel

| Hartmut Goebel          | h.goebel@crazy-compilers.com               |
| www.crazy-compilers.com | compilers which you thought are impossible |