From mboxrd@z Thu Jan  1 00:00:00 1970
From: ludo@gnu.org (Ludovic =?UTF-8?Q?Court=C3=A8s?=)
Subject: bug#22437: Fixing package-with-python2
Date: Sun, 07 Feb 2016 21:35:36 +0100
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To: Ricardo Wurmus <rekado@elephly.net>
Cc: guix-devel <guix-devel@gnu.org>, 22437@debbugs.gnu.org

Ricardo Wurmus <rekado@elephly.net> skribis:

> Efraim Flashner <efraim@flashner.co.il> writes:
>
>> On Wed, 03 Feb 2016 09:47:15 +0100
>> ludo@gnu.org (Ludovic Court=C3=A8s) wrote:
>>
>>> ludo@gnu.org (Ludovic Court=C3=A8s) skribis:
>>>=20
>>> > 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))))))
>>
>> This part I don't get. What's the period for?
>
> The =E2=80=9Cproperties=E2=80=9D field holds a regular alist.  Here the a=
list has one
> entry (a pair) with a symbol =E2=80=9Cpython2-variant=E2=80=9D as the key=
, and =E2=80=9C,(delay
> python2-foobar)=E2=80=9D as its value.
>
> The period is needed for the =E2=80=9Cdotted list=E2=80=9D syntax, which =
is used to
> distinguish a pair (or an improper list) from a well-formed list.

This is a relic of the old days and probably kind of confusing to
newcomers, but since we started making this field an alist, let=E2=80=99s k=
eep
it this way.

Ludo=E2=80=99.