From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Thompson, David" <dthompson2@worcester.edu>
Subject: Re: Fixing package-with-python2 (was: Package transformations)
Date: Mon, 1 Feb 2016 11:49:34 -0500
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To: Efraim Flashner <efraim@flashner.co.il>
Cc: guix-devel <guix-devel@gnu.org>

On Mon, Feb 1, 2016 at 11:35 AM, Efraim Flashner <efraim@flashner.co.il> wrote:

> Not all of our python packages are in python.scm. Currently in
> guix/build-system/python.scm we have:
>
> (define package-with-python2
>   ;; Note: delay call to 'default-python2' until after the 'arguments' field
>   ;; of packages is accessed to avoid a circular dependency when evaluating
>   ;; the top-level of (gnu packages python).
>   (package-with-explicit-python (delay (default-python2))
>                                 "python-" "python2-"))
>
> Excuse the code, but I think we're looking for something like:
>
> (define package-with-python2
>   (if (exists? python2-foo)
>     (python2-foo)
>     (package-with-explicit-python (delay (default-python2))
>                                   "python-" "python2-"))

I believe you just said the same thing I said.  We're on the same page.

- Dave