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: Change of Lisp syntax for "fancy" quotes in Emacs 27? Date: Thu, 4 Oct 2018 18:01:26 -0700 Organization: UCLA Computer Science Department Message-ID: References: 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 1538702151 18185 195.159.176.226 (5 Oct 2018 01:15:51 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Fri, 5 Oct 2018 01:15:51 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.0 Cc: Drew Adams To: Noam Postavsky , Emacs developers Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Fri Oct 05 03:15:46 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 1g8EiX-0004d2-BJ for ged-emacs-devel@m.gmane.org; Fri, 05 Oct 2018 03:15:45 +0200 Original-Received: from localhost ([::1]:60735 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1g8Eke-0008MF-17 for ged-emacs-devel@m.gmane.org; Thu, 04 Oct 2018 21:17:56 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:34285) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1g8Ejv-0008DZ-Ly for emacs-devel@gnu.org; Thu, 04 Oct 2018 21:17:15 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1g8EUo-00083X-KF for emacs-devel@gnu.org; Thu, 04 Oct 2018 21:01:39 -0400 Original-Received: from zimbra.cs.ucla.edu ([131.179.128.68]:34106) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1g8EUl-00081M-45 for emacs-devel@gnu.org; Thu, 04 Oct 2018 21:01:34 -0400 Original-Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id 98350160104; Thu, 4 Oct 2018 18:01:27 -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 EhSLDSHgArkO; Thu, 4 Oct 2018 18:01:26 -0700 (PDT) Original-Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id CEA2D160514; Thu, 4 Oct 2018 18:01:26 -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 sUVP_WG97c_0; Thu, 4 Oct 2018 18:01:26 -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 AE43C160104; Thu, 4 Oct 2018 18:01:26 -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: 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:230226 Archived-At: I'm afraid this patch is heading in the wrong direction, as we should be=20 more vigilant about confusables, not less. Consider this example, abstracted from the auth-source-secrets-create=20 source code: =C2=A0=C2=A0=C2=A0 (if (eq r 'secret) =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 (let ((data=E2=80=82data)) =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 (lambda () data)) =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 data) The intent of the (let ((data=E2=80=82data)) ...) code is to create a thu= nk=20 which, when evaluated, yields the current value of 'data' (not the value=20 of 'data' when the thunk is called), and that is what any human reading=20 the code will see. However, that is not what the code actually does. In=20 the (let ((data=E2=80=82data)) ...), the space between the two instances = of=20 'data' is really an EN SPACE (U+2002) so the 'let' is declaring an=20 identifier 'data=E2=80=82data' whose name contains an EN SPACE and whose = value=20 is nil, an identifier that is never used; so the thunk yields the later=20 value of 'data', not the earlier one. Because humans cannot reliably review source code containing characters=20 that are easily confusable with the ASCII symbols that are a basic part=20 of Elisp syntax, we should not be relaxing the reader to encourage=20 developers to use these characters in their identifiers. On the=20 contrary, we should be discouraging their use even more than we do now.