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: "The starting list count" ????? Date: Mon, 03 Jan 2022 16:15:32 -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="10812"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/29.0.50 (gnu/linux) Cc: emacs-devel@gnu.org To: Alan Mackenzie Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Mon Jan 03 22:16:24 2022 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 1n4Ugq-0002Wu-FG for ged-emacs-devel@m.gmane-mx.org; Mon, 03 Jan 2022 22:16:24 +0100 Original-Received: from localhost ([::1]:60238 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1n4Ugp-0004dw-DE for ged-emacs-devel@m.gmane-mx.org; Mon, 03 Jan 2022 16:16:23 -0500 Original-Received: from eggs.gnu.org ([209.51.188.92]:54680) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1n4Ug7-0003v8-Q3 for emacs-devel@gnu.org; Mon, 03 Jan 2022 16:15:39 -0500 Original-Received: from mailscanner.iro.umontreal.ca ([132.204.25.50]:51098) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1n4Ug5-0000hT-9n for emacs-devel@gnu.org; Mon, 03 Jan 2022 16:15:39 -0500 Original-Received: from pmg2.iro.umontreal.ca (localhost.localdomain [127.0.0.1]) by pmg2.iro.umontreal.ca (Proxmox) with ESMTP id 9D99D80602; Mon, 3 Jan 2022 16:15:35 -0500 (EST) Original-Received: from mail01.iro.umontreal.ca (unknown [172.31.2.1]) by pmg2.iro.umontreal.ca (Proxmox) with ESMTP id 66A1080272; Mon, 3 Jan 2022 16:15:34 -0500 (EST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=iro.umontreal.ca; s=mail; t=1641244534; bh=Dhc3NYDgBu/L13eCduZ7tgi/y7sQ9wwvS+lLaXaqY3Y=; h=From:To:Cc:Subject:References:Date:In-Reply-To:From; b=gmOwvfgWKcc5JpbwxRtkfllqsoiJqfT1RVTzGbS0KIMUx4JThGmp0D7H0kAPS267T HWClvsxxJyrZgh05ajtM8Q4tNYHfsQ/l0LltaB+wQROOvebiHjLhRg8dDqeoh0oMRU Rv6p6oZy5M+2DNt394PbGtXQuIrkGgyomeqR6Rq0NPMywmd73SLwKImC7JHwaF/zcv f9mGmmVJXeZoXRC5yDOuidwXJu60i0snduBEe8HXCHykLkKPtuKVJ9385yqSzSeirg 9jQuxpiIYnPnNj6WRrz4wyoImODWe83u7KnS0DV4jGsiollSl/vvjsBklsxXv3WTQo CSemIdYEOO2qQ== Original-Received: from ceviche (unknown [216.154.30.173]) by mail01.iro.umontreal.ca (Postfix) with ESMTPSA id E0AD1120370; Mon, 3 Jan 2022 16:15:33 -0500 (EST) In-Reply-To: (Alan Mackenzie's message of "Mon, 3 Jan 2022 21:03:33 +0000") Received-SPF: pass client-ip=132.204.25.50; envelope-from=monnier@iro.umontreal.ca; helo=mailscanner.iro.umontreal.ca X-Spam_score_int: -23 X-Spam_score: -2.4 X-Spam_bar: -- X-Spam_report: (-2.4 / 5.0 requ) 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=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.29 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:284102 Archived-At: > Debugger entered--Lisp error: (quit) > copy-tree((1 . #1) t) > macroexp-strip-symbol-positions((1 . #1)) > byte-compile-constant((1 . #1)) > byte-compile-quote('(1 . #2)) > byte-compile-form('(1 . #2)) > >> The #1 means "the second heap object between the root and here" and in >> (1 . #1) there's only one heap object. > > I can cope with "the second heap object", but what is "the root"? I suspect in the above backtrace, every arglist is passed to print as is, so the "root" is the arglist. >> (1 . #1) > > Yes. Looking at seq-tests.el, it's clear the original source for it is > > (let ((l1 '#1=(1 . #1#))) ....) Ah, one of those rare cases where the source code includes circular data. Maybe we should apply the patch below. Stefan diff --git a/test/lisp/emacs-lisp/seq-tests.el b/test/lisp/emacs-lisp/seq-tests.el index 9e5d59163f9..48ed72a1b06 100644 --- a/test/lisp/emacs-lisp/seq-tests.el +++ b/test/lisp/emacs-lisp/seq-tests.el @@ -474,7 +474,8 @@ test-sequences-oddp (should-error (seq-random-elt ""))) (ert-deftest test-seq-mapn-circular-lists () - (let ((l1 '#1=(1 . #1#))) + (let ((l1 (list 1))) + (setcdr l1 l1) (should (equal (seq-mapn #'+ '(3 4 5 7) l1) '(4 5 6 8)))))