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: Predicate for true lists Date: Sat, 7 Jul 2018 01:41:38 -0700 Organization: UCLA Computer Science Department Message-ID: <5d0d79d3-6291-fbf0-1028-064f86787483@cs.ucla.edu> References: <87fu3vdjjk.fsf@tcd.ie> <87bmcqhhsf.fsf@tcd.ie> <87in6xgtpb.fsf@tcd.ie> <2af892df-26cb-60b2-4fd8-067fcb3d32e9@cs.ucla.edu> <87r2kh9uwx.fsf@tcd.ie> <83h8lcnbxb.fsf@gnu.org> <6fc589d1-2c21-3e9b-be47-b7700f61642d@cs.ucla.edu> <831scflefs.fsf@gnu.org> 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 1530952789 19769 195.159.176.226 (7 Jul 2018 08:39:49 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Sat, 7 Jul 2018 08:39:49 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.8.0 Cc: contovob@tcd.ie, emacs-devel@gnu.org To: Eli Zaretskii Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sat Jul 07 10:39:44 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 1fbikq-00051t-Ib for ged-emacs-devel@m.gmane.org; Sat, 07 Jul 2018 10:39:44 +0200 Original-Received: from localhost ([::1]:32812 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fbimx-00021V-MO for ged-emacs-devel@m.gmane.org; Sat, 07 Jul 2018 04:41:55 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:52179) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fbims-00021P-0z for emacs-devel@gnu.org; Sat, 07 Jul 2018 04:41:50 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fbimq-0002ED-Vu for emacs-devel@gnu.org; Sat, 07 Jul 2018 04:41:50 -0400 Original-Received: from zimbra.cs.ucla.edu ([131.179.128.68]:57708) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fbiml-0002BK-C8; Sat, 07 Jul 2018 04:41:43 -0400 Original-Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id 467E0161634; Sat, 7 Jul 2018 01:41:41 -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 GQ4h1UkGlh9d; Sat, 7 Jul 2018 01:41:40 -0700 (PDT) Original-Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id ED021161668; Sat, 7 Jul 2018 01:41:39 -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 mJaLHdRNlEro; Sat, 7 Jul 2018 01:41:39 -0700 (PDT) Original-Received: from [192.168.1.9] (unknown [47.154.30.119]) by zimbra.cs.ucla.edu (Postfix) with ESMTPSA id 94031161634; Sat, 7 Jul 2018 01:41:39 -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: <831scflefs.fsf@gnu.org> Content-Language: en-US X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [fuzzy] 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:227040 Archived-At: Eli Zaretskii wrote: > the documentation still doesn't say that 'length' signals > an error for anything that is not a sequence, which is what > proper-list-p is relying on. The proposed implementation of proper-list-p does not rely on such a sign= al,=20 because it invokes 'length' only on nil and conses, and a cons must be ei= ther a=20 proper list, a dotted list, or a circular list. Since the 'length' docume= ntation=20 specifies behavior in all these cases, the proposed implementation of=20 proper-list-p does not need the 'length' documentation to also say that '= length'=20 signals an error for non-sequences. (Perhaps it is a good idea to add suc= h=20 documentation for other reasons, but that's a different matter.)