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.help Subject: Re: FW: How to avoid compiler warning `unused lexical variable' for `dolist' or `dotimes'? Date: Thu, 07 Jan 2021 22:31:25 -0500 Message-ID: References: <87o8i1ou7m.fsf@zoho.eu> <0db0bc9d-7efb-4d3e-8462-545d0a5b25f5@default> <8597f001-8057-483b-b108-819f66eac879@default> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="8322"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.0.50 (gnu/linux) Cc: help-gnu-emacs@gnu.org To: Drew Adams Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Fri Jan 08 04:31:57 2021 Return-path: Envelope-to: geh-help-gnu-emacs@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 1kxiVI-00025h-Ob for geh-help-gnu-emacs@m.gmane-mx.org; Fri, 08 Jan 2021 04:31:56 +0100 Original-Received: from localhost ([::1]:58286 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kxiVH-0004n5-Qx for geh-help-gnu-emacs@m.gmane-mx.org; Thu, 07 Jan 2021 22:31:55 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:41332) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kxiUs-0004l1-JC for help-gnu-emacs@gnu.org; Thu, 07 Jan 2021 22:31:31 -0500 Original-Received: from mailscanner.iro.umontreal.ca ([132.204.25.50]:43722) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kxiUq-0003Iv-R8 for help-gnu-emacs@gnu.org; Thu, 07 Jan 2021 22:31:30 -0500 Original-Received: from pmg2.iro.umontreal.ca (localhost.localdomain [127.0.0.1]) by pmg2.iro.umontreal.ca (Proxmox) with ESMTP id 30D908021A; Thu, 7 Jan 2021 22:31:28 -0500 (EST) Original-Received: from mail01.iro.umontreal.ca (unknown [172.31.2.1]) by pmg2.iro.umontreal.ca (Proxmox) with ESMTP id DBF7F807E8; Thu, 7 Jan 2021 22:31:26 -0500 (EST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=iro.umontreal.ca; s=mail; t=1610076686; bh=51M8heMOnzIu1lwI5ZKFgv2BElKeExzDKqmB3yJWi5g=; h=From:To:Cc:Subject:References:Date:In-Reply-To:From; b=TtqFnTewZ9KVY2HChs9i0GRRJQGADm9yv+qBxOcbwYu6DNIcH1cmAQRpDyzpuGtL2 bQw36y01ppcajrXGBMHji3WFz63wtSB4DJFw3gKy8BL6ABc2t8u/VlGbrHYTUnytf7 Tp5W0i5Lb7uSoMITtKsKIuK0/XRdx+EVNcz8Ive41ad9TiM6hWvkdE+zITBmG0ev2r fdklPlR1IkuCj3DZbcpVrtpzfR453x0hi3owigrQy7Y7yrC5kZC4DifiuCSj1SAdLV Ja4I39GKPmyQrr5V6A47/he6cPy8/JmUrDk1z7fyxgSHK8yBQegiRkC/Hzb77EJOFY /r5KRS9Z5pdZw== Original-Received: from alfajor (unknown [45.72.224.181]) by mail01.iro.umontreal.ca (Postfix) with ESMTPSA id 826D212047F; Thu, 7 Jan 2021 22:31:26 -0500 (EST) In-Reply-To: <8597f001-8057-483b-b108-819f66eac879@default> (Drew Adams's message of "Thu, 7 Jan 2021 19:08:05 -0800 (PST)") Received-SPF: pass client-ip=132.204.25.50; envelope-from=monnier@iro.umontreal.ca; helo=mailscanner.iro.umontreal.ca 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: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Users list for the GNU Emacs text editor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Original-Sender: "help-gnu-emacs" Xref: news.gmane.io gmane.emacs.help:127084 Archived-At: >> The third arg is different from "the expression after `dotimes`" in one >> important respect: the third arg can refer to the iteration variable >> which will contain the "last" value: >> (dotimes (i 10 i) nil) >> will return 10. > > In Common Lisp, at least, both dolist and dotimes let the return expression > you specify refer to the iteration variable. The difference is that for > dolist the value at the end is nil; for dotimes it is the number > of iterations. IIRC we consciously decided to break this compatibility in `dolist` because a variable that's always bound to nil is not useful enough to justify the extra hassle. Stefan