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: If records are not sequences, why does aref work on records? Date: Fri, 7 Apr 2017 09:56:43 -0700 Organization: UCLA Computer Science Department Message-ID: <0e6a0a16-8133-b2bc-404a-d0016f0c655e@cs.ucla.edu> References: <86pogo4vty.fsf@molnjunk.nocrew.org> <8360igof0k.fsf@gnu.org> <867f2w4qdk.fsf@molnjunk.nocrew.org> 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 1491584230 26767 195.159.176.226 (7 Apr 2017 16:57:10 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Fri, 7 Apr 2017 16:57:10 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 To: emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Fri Apr 07 18:57:06 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 1cwXBy-0005uM-UE for ged-emacs-devel@m.gmane.org; Fri, 07 Apr 2017 18:56:59 +0200 Original-Received: from localhost ([::1]:51905 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cwXC4-0004fq-U3 for ged-emacs-devel@m.gmane.org; Fri, 07 Apr 2017 12:57:04 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:49121) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cwXBu-0004du-0T for emacs-devel@gnu.org; Fri, 07 Apr 2017 12:56:58 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cwXBp-00031J-4v for emacs-devel@gnu.org; Fri, 07 Apr 2017 12:56:54 -0400 Original-Received: from zimbra.cs.ucla.edu ([131.179.128.68]:48906) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cwXBo-000311-UY for emacs-devel@gnu.org; Fri, 07 Apr 2017 12:56:49 -0400 Original-Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id 5E2DB1600A2 for ; Fri, 7 Apr 2017 09:56:47 -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 lrKjHZqFhy7h for ; Fri, 7 Apr 2017 09:56:46 -0700 (PDT) Original-Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id 95C741600A6 for ; Fri, 7 Apr 2017 09:56:46 -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 QCei8OlNrJ6R for ; Fri, 7 Apr 2017 09:56:46 -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 7D9521600A2 for ; Fri, 7 Apr 2017 09:56:46 -0700 (PDT) In-Reply-To: <867f2w4qdk.fsf@molnjunk.nocrew.org> 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:213764 Archived-At: On 04/07/2017 12:40 AM, Lars Brinkhoff wrote: > I think there are only a few functions that wants a sequence but not a > record: elt, copy-sequence, concat, reverse, and sort. It is confusing that aref works on records but copy-sequence etc. do not. This behavior of aref is not documented in the aref doc string, or in the Lisp manual under aref. How about if we define a new function record-ref to be used on records, instead of aref? At the low level this would insulate records better from the rest of Emacs Lisp, which I think is the intent -- as I understand it, records are supposed to be used to create new types, and are not supposed to be sorts of aliases for sequences.