From mboxrd@z Thu Jan  1 00:00:00 1970
From: ludo@gnu.org (Ludovic =?UTF-8?Q?Court=C3=A8s?=)
Subject: bug#27572: simultaneous installation of python2 and python3 fails
Date: Fri, 07 Jul 2017 13:27:01 +0200
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In-Reply-To: <877ezoivqd.fsf@GlaDOS.home> (Diego Nicola Barbato's message of
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To: Diego Nicola Barbato <dnbarbato@posteo.de>
Cc: 27572@debbugs.gnu.org

Hello Diego,

Diego Nicola Barbato <dnbarbato@posteo.de> skribis:

> When running the command "guix pull && guix package -i python@2 python"
> instead of installing the latest version of python2 and python3, as it
> used to do until about four weeks ago, guix gives following error
> message (hash values replaced with ...):
>
>   guix package: error: profile contains conflicting entries for python:out
>   guix package: error:   first entry: python@2.7.13:out /gnu/store/...-py=
thon-2.7.13
>   guix package: error:   second entry: python@3.5.3:out /gnu/store/...-py=
thon-3.5.3

Indeed, Guix now refuses to install two different versions or variants
of the same package since in general they would conflict.

In this particular case, they do not actually conflict, I think, since
python@3 provides executables prefixed by =E2=80=9C3=E2=80=9D whereas pytho=
n@2 does not.

Perhaps we should rename =E2=80=9Cpython=E2=80=9D to =E2=80=9Cpython2=E2=80=
=9D or something like that?

In the meantime, I recommend using separate profiles for your Python 2
and Python 3 development environments.  Is that a viable option for you?

Thanks,
Ludo=E2=80=99.