From mboxrd@z Thu Jan  1 00:00:00 1970
From: ludo@gnu.org (Ludovic =?utf-8?Q?Court=C3=A8s?=)
Subject: Re: We need to generalize 'package-with-python2'
Date: Sun, 08 Feb 2015 00:12:13 +0100
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References: <87siembm0k.fsf@netris.org> <20150203214713.47d2fd1b@PocketWee>
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In-Reply-To: <20150203214713.47d2fd1b@PocketWee> (Eric Bavier's message of
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To: Eric Bavier <bavier@member.fsf.org>
Cc: guix-devel@gnu.org

Eric Bavier <bavier@member.fsf.org> skribis:

> On Tue, 03 Feb 2015 18:42:03 -0500
> Mark H Weaver <mhw@netris.org> wrote:
>
>> The 'python-dbus' package (called 'dbus-python' upsteam) uses the
>> 'gnu-build-system', and like most other python libraries, there will
>> be two variants: 'python-dbus' and 'python2-dbus'.  Unfortunately,
>> 'package-with-python2' only works on packages that use
>> 'python-build-system'.  This is a problem.
>>=20
>> It wouldn't be so bad to use 'inherit' to create 'python2-dbus' from
>> 'python-dbus', but the more serious problem is that unless we
>> generalize 'package-with-python2', it won't work properly on any
>> package that uses 'python-dbus' as an input.
>>=20
>> On the other hand, I realize that 'package-with-explicit-python'
>> intentionally avoids traversing into packages unless they use
>> 'python-build-system', and that this is important for efficiency.
>>=20
>> Any thoughts on how best to solve this?
>
> Would it be enough to stop recursion when the bag inputs no longer
> contain a python?

Perhaps, but there=E2=80=99s also the problem that there=E2=80=99s no gener=
ic way to
communicate the Python to use (#:python in =E2=80=98python-build-system=E2=
=80=99) to
arbitrary build systems.

I=E2=80=99m not sure how to solve the problem Mark raises.

Perhaps =E2=80=98package-with-python2=E2=80=99 could be passed a set of map=
pings; we=E2=80=99d
give it the python-dbus -> python2-dbus mapping and it would just honor
it.  Thoughts?

Ludo=E2=80=99.