From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: =?utf-8?Q?Mattias_Engdeg=C3=A5rd?= Newsgroups: gmane.emacs.devel Subject: Re: lexicographic list comparison Date: Sat, 10 Sep 2022 11:07:49 +0200 Message-ID: References: Mime-Version: 1.0 (Mac OS X Mail 14.0 \(3654.120.0.1.13\)) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="27703"; mail-complaints-to="usenet@ciao.gmane.io" Cc: emacs-devel@gnu.org To: sds@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Sat Sep 10 11:09:39 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 1oWwUd-00076a-K2 for ged-emacs-devel@m.gmane-mx.org; Sat, 10 Sep 2022 11:09:39 +0200 Original-Received: from localhost ([::1]:51960 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1oWwUc-0006aw-Hq for ged-emacs-devel@m.gmane-mx.org; Sat, 10 Sep 2022 05:09:38 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:51348) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oWwT4-0005sb-8N for emacs-devel@gnu.org; Sat, 10 Sep 2022 05:08:02 -0400 Original-Received: from mail1450c50.megamailservers.eu ([91.136.14.50]:42658 helo=mail265c50.megamailservers.eu) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oWwT1-0001QV-CR for emacs-devel@gnu.org; Sat, 10 Sep 2022 05:08:01 -0400 X-Authenticated-User: mattiase@bredband.net DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=megamailservers.eu; s=maildub; t=1662800873; bh=IdLvu9sRwsuiE/PC7Tvq+vDbWoRr8JiKA5hfY6Wzi/s=; h=Subject:From:In-Reply-To:Date:Cc:References:To:From; b=qnsy1nAhZ846dMQBukmKJ+YTvx4yb367Cc8fY+B8PtqAUl9YEMY4CXKrV/foSnNg7 rI+5jkjgpYKoePZ1tnM8PvhkdrMoUIqRj0Uc0jNfqTexuz6IqkI4SCeuwYYUufYFWL tm92/TdEi8Pj8Ee1GVAfZou4hr4BPY4DNzcYlDuw= Feedback-ID: mattiase@acm.or Original-Received: from smtpclient.apple (c188-150.188-179.bredband.tele2.se [188.150.188.179] (may be forged)) (authenticated bits=0) by mail265c50.megamailservers.eu (8.14.9/8.13.1) with ESMTP id 28A97oFs045018; Sat, 10 Sep 2022 09:07:52 +0000 In-Reply-To: X-Mailer: Apple Mail (2.3654.120.0.1.13) X-CTCH-RefID: str=0001.0A782F1D.631C53E9.000E, ss=1, re=0.000, recu=0.000, reip=0.000, cl=1, cld=1, fgs=0 X-CTCH-VOD: Unknown X-CTCH-Spam: Unknown X-CTCH-Score: 0.000 X-CTCH-Flags: 0 X-CTCH-ScoreCust: 0.000 X-Origin-Country: SE Received-SPF: softfail client-ip=91.136.14.50; envelope-from=mattiase@acm.org; helo=mail265c50.megamailservers.eu X-Spam_score_int: -11 X-Spam_score: -1.2 X-Spam_bar: - X-Spam_report: (-1.2 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, SPF_HELO_NONE=0.001, SPF_SOFTFAIL=0.665, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=no 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:295112 Archived-At: 9 sep. 2022 kl. 21.27 skrev Sam Steingold : > What do you do when sorting a list of lists of numbers? Sigh deeply and write ad-hoc code for the nth time. > Or maybe sorting lists of lists is just such a rare op that no one has > ever encountered it before me? It would be useful to have a total ordering on Lisp values: for = heterogeneous ordered collections, for simplifying multi-key sorting, = for normalising unordered collections, etc. The devil is in the details: are strings compared with our without = properties? Do we observe the wonky IEEE rules for ordering floats? Is = there a particularly useful ordering between elements of different = types? Do we need to worry about circularity? How do we compare hash = tables? And so on. Consistency with `equal` would be desirable (up to hash table identity, = perhaps).