From mboxrd@z Thu Jan  1 00:00:00 1970
From: =?utf-8?Q?Ludovic_Court=C3=A8s?= <ludo@gnu.org>
Subject: Re: bug#38529: Make --ad-hoc the default for guix environment
 proposed deprecation mechanism
Date: Mon, 16 Dec 2019 23:09:37 +0100
Message-ID: <87k16vdise.fsf@gnu.org>
References: <87eexeu8mo.fsf@ambrevar.xyz>
 <CAJ3okZ3WnG87m=jQw08M9ER+=9FS0NVx=uALHK_-4LuD50KhvA@mail.gmail.com>
 <CAE4v=phY+7CTKMf8Y3a9p4okfqtMGOWu9kd2Nu6oCJW8OsK3Lw@mail.gmail.com>
 <CAJ3okZ3+-yAfRpYDHz-jYONguOPWjff0iWZ_7NPEz6x5mbOO1w@mail.gmail.com>
 <CAE4v=piMnBhHWpbB60qMRnnDNwqkuddfNv7cEihr9+5-52k2OA@mail.gmail.com>
 <CAJ3okZ3gJDdDKWERLANp+7ueSirEZ7hH=YKa3nhCAzCzAz1TGg@mail.gmail.com>
 <CAE4v=pgevGwP6+jSY-+0DPdtvK60sEvd-uibqhRawuo6N1pL-Q@mail.gmail.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: quoted-printable
Return-path: <guix-devel-bounces+gcggd-guix-devel=m.gmane.org@gnu.org>
Received: from eggs.gnu.org ([2001:470:142:3::10]:35696)
 by lists.gnu.org with esmtp (Exim 4.90_1)
 (envelope-from <ludo@gnu.org>) id 1igyYe-00049q-Ld
 for guix-devel@gnu.org; Mon, 16 Dec 2019 17:09:41 -0500
In-Reply-To: <CAE4v=pgevGwP6+jSY-+0DPdtvK60sEvd-uibqhRawuo6N1pL-Q@mail.gmail.com>
 (=?utf-8?Q?=22G=C3=A1bor?= Boskovits"'s message of "Fri, 13 Dec 2019
 17:27:52 +0100")
List-Id: "Development of GNU Guix and the GNU System distribution."
 <guix-devel.gnu.org>
List-Unsubscribe: <https://lists.gnu.org/mailman/options/guix-devel>,
 <mailto:guix-devel-request@gnu.org?subject=unsubscribe>
List-Archive: <https://lists.gnu.org/archive/html/guix-devel>
List-Post: <mailto:guix-devel@gnu.org>
List-Help: <mailto:guix-devel-request@gnu.org?subject=help>
List-Subscribe: <https://lists.gnu.org/mailman/listinfo/guix-devel>,
 <mailto:guix-devel-request@gnu.org?subject=subscribe>
Errors-To: guix-devel-bounces+gcggd-guix-devel=m.gmane.org@gnu.org
Sender: "Guix-devel" <guix-devel-bounces+gcggd-guix-devel=m.gmane.org@gnu.org>
To: =?utf-8?Q?G=C3=A1bor?= Boskovits <boskovits@gmail.com>
Cc: Guix-devel <guix-devel@gnu.org>, 38529@debbugs.gnu.org

Hello,

G=C3=A1bor Boskovits <boskovits@gmail.com> skribis:

> So in a more algorithmic manner:
> 1. if ad-hoc and inputs-of is present at the same invocation: fail
> hard. (With an error like incompatible options present)
> 2. if only ad-hoc is present, then print a deprecation warning (yes,
> we could make this suspendable with an environment variable, like you
> described)
> 3. if only inputs-of present, then do the new behaviour.
> 4. if neither ad-hoc nor inputs-of present then
>   a. if GUIX_ENVIRONMENT_DEPRECATED is 1: do the current behaviour,
>   b. if GUIX_ENVIRONMENT_DEPRECATED is undefined, or is not 1: do the
> new behaviour.

That sounds like a good plan to me.

#4 is the trickiest, and I think it=E2=80=99d be good to give users a bit of
time so they can start adjusting before deprecation is in effect.

Namely, we could start by introducing =E2=80=98--inputs-of=E2=80=99 and emi=
tting a
warning in case #4 to suggest the use of =E2=80=98--inputs-of=E2=80=99.  Ap=
art from the
warning, case #4 would still behave the same as now.

Three (?) months later, we implement what you describe above.  Hopefully
by that time many people got used to =E2=80=98--inputs-of=E2=80=99.

Thoughts?

Ludo=E2=80=99.