From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Stefan Monnier via "Bug reports for GNU Emacs, the Swiss army knife of text editors" Newsgroups: gmane.emacs.bugs Subject: bug#55395: What does (1 2 3 . #2) mean? Date: Fri, 13 May 2022 13:20:51 -0400 Message-ID: References: <4B70C9BE-B784-4B74-A081-7A8B3F8D5136@acm.org> <87ilq931ay.fsf@gnus.org> Reply-To: Stefan Monnier Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="15858"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/29.0.50 (gnu/linux) Cc: 55395@debbugs.gnu.org, Mattias =?UTF-8?Q?Engdeg=C3=A5rd?= To: Lars Ingebrigtsen Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Fri May 13 19:22:17 2022 Return-path: Envelope-to: geb-bug-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 1npYzY-0003vX-FR for geb-bug-gnu-emacs@m.gmane-mx.org; Fri, 13 May 2022 19:22:16 +0200 Original-Received: from localhost ([::1]:48826 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1npYzX-0003Mj-1h for geb-bug-gnu-emacs@m.gmane-mx.org; Fri, 13 May 2022 13:22:15 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:47166) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1npYzP-0003L5-Ej for bug-gnu-emacs@gnu.org; Fri, 13 May 2022 13:22:07 -0400 Original-Received: from debbugs.gnu.org ([209.51.188.43]:51038) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1npYzK-0000Hp-DZ for bug-gnu-emacs@gnu.org; Fri, 13 May 2022 13:22:07 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1npYzK-0002lY-70 for bug-gnu-emacs@gnu.org; Fri, 13 May 2022 13:22:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Stefan Monnier Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Fri, 13 May 2022 17:22:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 55395 X-GNU-PR-Package: emacs Original-Received: via spool by 55395-submit@debbugs.gnu.org id=B55395.165246246210534 (code B ref 55395); Fri, 13 May 2022 17:22:02 +0000 Original-Received: (at 55395) by debbugs.gnu.org; 13 May 2022 17:21:02 +0000 Original-Received: from localhost ([127.0.0.1]:44935 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1npYyM-0002jp-6A for submit@debbugs.gnu.org; Fri, 13 May 2022 13:21:02 -0400 Original-Received: from mailscanner.iro.umontreal.ca ([132.204.25.50]:47384) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1npYyK-0002iy-Dm for 55395@debbugs.gnu.org; Fri, 13 May 2022 13:21:00 -0400 Original-Received: from pmg2.iro.umontreal.ca (localhost.localdomain [127.0.0.1]) by pmg2.iro.umontreal.ca (Proxmox) with ESMTP id 6B3AB806F8; Fri, 13 May 2022 13:20:54 -0400 (EDT) Original-Received: from mail01.iro.umontreal.ca (unknown [172.31.2.1]) by pmg2.iro.umontreal.ca (Proxmox) with ESMTP id 072EA80390; Fri, 13 May 2022 13:20:53 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=iro.umontreal.ca; s=mail; t=1652462453; bh=wwl+HdjokZCX0CMorQ8lDP3LJUMuA9XXC6o0ZLOIezA=; h=From:To:Cc:Subject:References:Date:In-Reply-To:From; b=TtDybZ3FGCsI26a3Bg/IS80Rf5Duy+/d5CPyR8ajcHx9phoEeZa8WakaqQa2xjflH FDpML4JF3nEpbU5yycvUr28fgGXCM9YSw4P6Ca3yYsrZAV94/hhIMzbFFhfoBTCu+c pUL3/2fPNscO7JXz340DNj9pO4huU0ygtHybRSnuL/1dfLxmL6sHMWg0MJ8XZyF9s0 KiDSjkE6s1bdD2mbZ0U+brOGhLKcUwd8j6dKffJ7xwGi/DG60I99/z72HL0ZRpINvn xUTzqzS9FjUGuLMeyxBqRlszx8UtyocTJaBrtbR950+l9lipore89UhGHchU5UK2dw D5+bpxp7lf49A== Original-Received: from pastel (unknown [45.72.221.51]) by mail01.iro.umontreal.ca (Postfix) with ESMTPSA id 9CDAE120837; Fri, 13 May 2022 13:20:52 -0400 (EDT) In-Reply-To: <87ilq931ay.fsf@gnus.org> (Lars Ingebrigtsen's message of "Fri, 13 May 2022 17:22:13 +0200") X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-BeenThere: bug-gnu-emacs@gnu.org List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Original-Sender: "bug-gnu-emacs" Xref: news.gmane.io gmane.emacs.bugs:232180 Archived-At: >> It may have made more sense before the switch of cycle-detection algorit= hm >> from Floyd to Brent. This can be fixed by hand-coding the list iteration >> and explicitly remembering the index of the tortoise, but would that be >> correct? What's the spec? > > I don't think I've ever considered #x to be meaningful outside of > print-circle, but I guess if we wanted to have some semantics here, I > think I would have expected the index of the tortoise? But... Agreed (and agreed with Andreas as well). The main goal is to avoid inf-looping and the #NNN chosen is somewhat arbitrary. I don't think it's worth it to try and make those #NNN more precise. If the arbitrariness of the specific #NNN chosen is a problem, we could replace it with a fixed `#=A1cycle!` or something like that (or if we want it to be more user-readable we could print something like #cycle: where OBJ is the first N layers of the rest of the cycle, like (rho 0 2) =3D> (1 2 1 2 . #cycle:(1 2 1 ...)) I'm personally more bothered by the fact that those #NNN use exactly the same syntax as used with `print-circle` yet they don't have the same semantics. Stefan