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: type-of semantics unclear for records Date: Tue, 4 Apr 2017 15:12:17 -0700 Organization: UCLA Computer Science Department Message-ID: <5a8f7878-6731-2d9f-36dc-52f06e680697@cs.ucla.edu> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-Trace: blaine.gmane.org 1491343981 19483 195.159.176.226 (4 Apr 2017 22:13:01 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Tue, 4 Apr 2017 22:13:01 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 To: Emacs development discussions Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Wed Apr 05 00:12:57 2017 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 1cvWh2-0004GH-Cq for ged-emacs-devel@m.gmane.org; Wed, 05 Apr 2017 00:12:52 +0200 Original-Received: from localhost ([::1]:37810 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cvWh8-0007Lb-1W for ged-emacs-devel@m.gmane.org; Tue, 04 Apr 2017 18:12:58 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:40634) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cvWga-0007LU-9r for emacs-devel@gnu.org; Tue, 04 Apr 2017 18:12:25 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cvWgX-0000vx-6k for emacs-devel@gnu.org; Tue, 04 Apr 2017 18:12:24 -0400 Original-Received: from zimbra.cs.ucla.edu ([131.179.128.68]:43538) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cvWgW-0000vh-W8 for emacs-devel@gnu.org; Tue, 04 Apr 2017 18:12:21 -0400 Original-Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id CA3571600A5 for ; Tue, 4 Apr 2017 15:12:18 -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 LKjJC7ZTNMqZ for ; Tue, 4 Apr 2017 15:12:18 -0700 (PDT) Original-Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id 20E4E1600A6 for ; Tue, 4 Apr 2017 15:12:18 -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 18ybiNgJy7kN for ; Tue, 4 Apr 2017 15:12:18 -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 086981600A5 for ; Tue, 4 Apr 2017 15:12:18 -0700 (PDT) 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:213659 Archived-At: The recently-changed behavior of 'type-of' causes it to disagree with its documentation when the type of a record is itself a record. For example, the documentation implies that (eq X (type-of (record X))) should be t for all X, but this is not the case when X is (record 'a 'b), because in this case (type-of (record X)) returns b. I assume the behavior is intended to support subclassing of some sort; if so the subclassing should be documented (or at least the doc should say that behavior is undefined if the record type is not a symbol), and if not the behavior should be changed to agree with the doc.