From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Paul Eggert Newsgroups: gmane.emacs.devel Subject: Re: Why is there no `until' in elisp? Date: Wed, 17 Oct 2018 14:35:13 -0700 Organization: UCLA Computer Science Department Message-ID: <5e6f544e-811f-fc0a-bc08-e77d601a4c4d@cs.ucla.edu> References: <87murdu6to.fsf@portable.galex-713.eu> <87lg6xgc58.fsf@portable.galex-713.eu> <86294998-2c96-a1be-6a83-2e34b7fa6046@cs.ucla.edu> <87d0s86zrs.fsf@portable.galex-713.eu> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: quoted-printable X-Trace: blaine.gmane.org 1539812018 22059 195.159.176.226 (17 Oct 2018 21:33:38 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Wed, 17 Oct 2018 21:33:38 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 Cc: Yuri Khan , Stefan Monnier , Emacs developers To: "Garreau, Alexandre" Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Wed Oct 17 23:33:33 2018 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1gCtRd-0005d9-Dm for ged-emacs-devel@m.gmane.org; Wed, 17 Oct 2018 23:33:33 +0200 Original-Received: from localhost ([::1]:39186 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gCtTj-0005KJ-Su for ged-emacs-devel@m.gmane.org; Wed, 17 Oct 2018 17:35:43 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:50730) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gCtTS-0005Iz-My for emacs-devel@gnu.org; Wed, 17 Oct 2018 17:35:27 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gCtTN-0002Ii-NS for emacs-devel@gnu.org; Wed, 17 Oct 2018 17:35:26 -0400 Original-Received: from zimbra.cs.ucla.edu ([131.179.128.68]:42846) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gCtTN-00029S-Bj for emacs-devel@gnu.org; Wed, 17 Oct 2018 17:35:21 -0400 Original-Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id 6A455161752; Wed, 17 Oct 2018 14:35:14 -0700 (PDT) Original-Received: from zimbra.cs.ucla.edu ([127.0.0.1]) by localhost (zimbra.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id D6Ff3pKJuwWc; Wed, 17 Oct 2018 14:35:13 -0700 (PDT) Original-Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id A771F16177A; Wed, 17 Oct 2018 14:35:13 -0700 (PDT) X-Virus-Scanned: amavisd-new at zimbra.cs.ucla.edu Original-Received: from zimbra.cs.ucla.edu ([127.0.0.1]) by localhost (zimbra.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id tJdlAq13Bd7Z; Wed, 17 Oct 2018 14:35:13 -0700 (PDT) Original-Received: from Penguin.CS.UCLA.EDU (Penguin.CS.UCLA.EDU [131.179.64.200]) by zimbra.cs.ucla.edu (Postfix) with ESMTPSA id 84EB8161752; Wed, 17 Oct 2018 14:35:13 -0700 (PDT) Openpgp: preference=signencrypt Autocrypt: addr=eggert@cs.ucla.edu; prefer-encrypt=mutual; keydata= xsFNBEyAcmQBEADAAyH2xoTu7ppG5D3a8FMZEon74dCvc4+q1XA2J2tBy2pwaTqfhpxxdGA9 Jj50UJ3PD4bSUEgN8tLZ0san47l5XTAFLi2456ciSl5m8sKaHlGdt9XmAAtmXqeZVIYX/UFS 96fDzf4xhEmm/y7LbYEPQdUdxu47xA5KhTYp5bltF3WYDz1Ygd7gx07Auwp7iw7eNvnoDTAl KAl8KYDZzbDNCQGEbpY3efZIvPdeI+FWQN4W+kghy+P6au6PrIIhYraeua7XDdb2LS1en3Ss mE3QjqfRqI/A2ue8JMwsvXe/WK38Ezs6x74iTaqI3AFH6ilAhDqpMnd/msSESNFt76DiO1ZK QMr9amVPknjfPmJISqdhgB1DlEdw34sROf6V8mZw0xfqT6PKE46LcFefzs0kbg4GORf8vjG2 Sf1tk5eU8MBiyN/bZ03bKNjNYMpODDQQwuP84kYLkX2wBxxMAhBxwbDVZudzxDZJ1C2VXujC OJVxq2kljBM9ETYuUGqd75AW2LXrLw6+MuIsHFAYAgRr7+KcwDgBAfwhPBYX34nSSiHlmLC+ KaHLeCLF5ZI2vKm3HEeCTtlOg7xZEONgwzL+fdKo+D6SoC8RRxJKs8a3sVfI4t6CnrQzvJbB n6gxdgCu5i29J1QCYrCYvql2UyFPAK+do99/1jOXT4m2836j1wARAQABzSBQYXVsIEVnZ2Vy dCA8ZWdnZXJ0QGNzLnVjbGEuZWR1PsLBfgQTAQIAKAUCTIByZAIbAwUJEswDAAYLCQgHAwIG FQgCCQoLBBYCAwECH In-Reply-To: <87d0s86zrs.fsf@portable.galex-713.eu> Content-Language: en-US X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 131.179.128.68 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.org gmane.emacs.devel:230463 Archived-At: On 10/17/18 2:15 PM, Garreau, Alexandre wrote: > =E2=80=9Cwhile=E2=80=9D as used in natural language does *not* mean the= same thing Yes, of course. And the same is true for "until". But I'm not objecting=20 to the keyword's spelling: I'm objecting to a syntax where a condition C=20 is placed immediately before a place where C is false. This is=20 confusing! When I read "C" I should be mentally thinking "OK, now C is=20 true". This is elementary notation design. > It is still more natural and meaningful to say =E2=80=9Cuntil I=E2=80=99= m not hungry > anymore I eat=E2=80=9D instead of =E2=80=9Cwhile I=E2=80=99m hungry I e= at=E2=80=9D, Not at all. Most English-speakers would say that the latter is far more=20 readable. >> the Elisp syntax for the proposed loop construct should *not* be >> (until C S). > And what should it be then? Why not use cl-loop? Although it's not perfect it's good enough, and=20 it's better than introducing a seemingly-simple but deeply confusing synt= ax.