From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.devel Subject: Re: Noob question: why sequences, lists in particular start at index 0 in Elisp? Date: Sun, 08 Nov 2020 09:42:42 -0500 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="20805"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.0.50 (gnu/linux) Cc: emacs-devel@gnu.org To: Arthur Miller Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Sun Nov 08 15:43:24 2020 Return-path: Envelope-to: ged-emacs-devel@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1kblud-0005Ju-IV for ged-emacs-devel@m.gmane-mx.org; Sun, 08 Nov 2020 15:43:23 +0100 Original-Received: from localhost ([::1]:40286 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kbluc-0007ER-LZ for ged-emacs-devel@m.gmane-mx.org; Sun, 08 Nov 2020 09:43:22 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:53302) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kblu8-0006ox-2Z for emacs-devel@gnu.org; Sun, 08 Nov 2020 09:42:52 -0500 Original-Received: from mailscanner.iro.umontreal.ca ([132.204.25.50]:35063) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kblu4-0002Bx-9Z for emacs-devel@gnu.org; Sun, 08 Nov 2020 09:42:50 -0500 Original-Received: from pmg2.iro.umontreal.ca (localhost.localdomain [127.0.0.1]) by pmg2.iro.umontreal.ca (Proxmox) with ESMTP id CEEC980B07; Sun, 8 Nov 2020 09:42:46 -0500 (EST) Original-Received: from mail01.iro.umontreal.ca (unknown [172.31.2.1]) by pmg2.iro.umontreal.ca (Proxmox) with ESMTP id 2668D80382; Sun, 8 Nov 2020 09:42:45 -0500 (EST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=iro.umontreal.ca; s=mail; t=1604846565; bh=YG8Z9oJUCMrHB2QyziqLIufXStssb0eXvHEHNbmRgaQ=; h=From:To:Cc:Subject:References:Date:In-Reply-To:From; b=UZey919yhmo5d+xqmLQS5ek9dD4huuoIqXnfz5b1DBporP0LDExQIBcXdcKWQFoer +kgqB/VtCScftme9O7Y/hyGiqf9M46HV06efQgYk68IFD14KlwaKVGN91F+aaKol/j edudM6nwl2jqkvhMFpKkCXLvETrafS9ulxr9qailm/Amb4mJ8qUiQPgk2GmP3iU4nZ q0TfpsI8HsXtl7mYEARWcsG1EYd3ng2+CWt18cLUR7TAQvpXylN7XKjkBEkfz2wlr4 yUGetJL3SN93FeM049wtTF5B5dfnT+GzkWImkK0f/0ykbuprPHLbEL+aziPUtxfJOC 9zCy8jNXZTTkg== Original-Received: from alfajor (unknown [157.52.9.240]) by mail01.iro.umontreal.ca (Postfix) with ESMTPSA id 83472120301; Sun, 8 Nov 2020 09:42:44 -0500 (EST) In-Reply-To: (Arthur Miller's message of "Sun, 08 Nov 2020 14:32:08 +0100") Received-SPF: pass client-ip=132.204.25.50; envelope-from=monnier@iro.umontreal.ca; helo=mailscanner.iro.umontreal.ca X-detected-operating-system: by eggs.gnu.org: First seen = 2020/11/08 08:39:36 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] X-Spam_score_int: -42 X-Spam_score: -4.3 X-Spam_bar: ---- X-Spam_report: (-4.3 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.23 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-mx.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.io gmane.emacs.devel:258902 Archived-At: > I understand why they do so in C; but why in Elisp? Why should it be different in ELisp? AFAIK, indexing should always be 0-based, so we don't get into silly "is 1900 in the 19th century or the 20th century". And indeed computer science got this mostly right, except for Fortran arrays and Emacs buffers. Stefan