From mboxrd@z Thu Jan  1 00:00:00 1970
From: ludo@gnu.org (Ludovic =?utf-8?Q?Court=C3=A8s?=)
Subject: Re: Fixing package-with-python2
Date: Mon, 01 Feb 2016 23:07:40 +0100
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	(David Thompson's message of "Mon, 1 Feb 2016 08:49:10 -0500")
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To: "Thompson, David" <dthompson2@worcester.edu>
Cc: guix-devel <guix-devel@gnu.org>

"Thompson, David" <dthompson2@worcester.edu> skribis:

> On Mon, Feb 1, 2016 at 8:06 AM, Efraim Flashner <efraim@flashner.co.il> w=
rote:
>
>> I looked over the commit but not deeply enough yet, would it be possible=
 to
>> use some of the logic in this to fix the package-with-python2 issue?
>
> Here's a potential solution for 'package-with-python2': module
> introspection.

Evil!  ;-)

An idea I haven=E2=80=99t taken the time to test yet would be to use
=E2=80=98properties=E2=80=99:

  (define python-foobar   ;with Python 3
    (package
      (name "foobar")
      ;; Specify which Python 2 variant to use.
      (properties `((python2-variant . ,(delay python2-foobar))))))

  (define python2-foobar
    (package (inherit python-foobar)
      ;; =E2=80=A6 stuff beyond the mechanical python 2=E2=86=923 switch=E2=
=80=A6
      ))

=E2=80=98package-with-python2=E2=80=99 would honor this =E2=80=98python2-va=
riant=E2=80=99 property.

Thoughts?

Ludo=E2=80=99.