From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Juanma Barranquero Newsgroups: gmane.emacs.devel Subject: Re: Warn about comparing quoted lists (etc) using `eq` Date: Thu, 15 Dec 2022 08:00:19 +0100 Message-ID: References: <8D624413-5A6C-46D7-A4EB-53C23F7CC4D3@gmail.com> <87359h8968.fsf@web.de> Mime-Version: 1.0 Content-Type: multipart/alternative; boundary="00000000000014b27105efd86a25" Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="30351"; mail-complaints-to="usenet@ciao.gmane.io" Cc: =?UTF-8?Q?Mattias_Engdeg=C3=A5rd?= , emacs-devel@gnu.org To: "Dr. Arne Babenhauserheide" Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Thu Dec 15 08:01:30 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 1p5iFG-0007hC-4N for ged-emacs-devel@m.gmane-mx.org; Thu, 15 Dec 2022 08:01:30 +0100 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1p5iEn-0004XU-Hn; Thu, 15 Dec 2022 02:01:01 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1p5iEl-0004X0-82 for emacs-devel@gnu.org; Thu, 15 Dec 2022 02:00:59 -0500 Original-Received: from mail-ed1-x536.google.com ([2a00:1450:4864:20::536]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1p5iEj-0003jU-3x for emacs-devel@gnu.org; Thu, 15 Dec 2022 02:00:58 -0500 Original-Received: by mail-ed1-x536.google.com with SMTP id i9so12902542edj.4 for ; Wed, 14 Dec 2022 23:00:56 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=hHKkHp22mAYZD4OgIMLp+KyLHFyFhv2y77I2WeG6qtA=; b=lQaA9Dy60YAkBkqR6CnmY8sO33dkYJfAB4/wcHsJ8e8nZiL9wJXTF849Iz5JcZM8G5 BraNBbqtY+MZVBEffS7ppAWrmprkrFIpgVmVPIuYr9xTJ58VAnOdK6BhSgKIGB5W5tsP NnV+ag/VX+n5QBEV5x5w/pLCt/vdqo2xIzPz8B4pqVmgGObg1Fxt52HgygdFZT2cRb/y ZDyLEvqeBgcCuj2rSoqQy61VsHWrHbiv6Lfwb68XFtFUhUuLgAZ1Z35TxCpwGh7kuJRb MPC6oUNhjXVTBWbR1MwncWlnbHc07Q3ELEhNGUt8f4d44x5j3cw9FX2ZIKtdCHzZYmcS WzRw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=hHKkHp22mAYZD4OgIMLp+KyLHFyFhv2y77I2WeG6qtA=; b=tDzouymf3U1T+miuC1G2nn4RC0XsdN+f45eS1k4IwFlqszX8YqofFS2Xl7JP1iA6yq npMUU5uhDy+jauWvYU2xA12DrqHNdlu6XuyXCU6GWkAccsbxSXQ92hvzukWnkO+VxyeP 2/1LmzXz4iXC0M80iTKNiz8oIX6Ea5ZwDTIlzRTIgC6FqA2jHMszd+F4R8HE106xYjs0 3Q7Z1+886u+cWvPS/HLEwaRfXB1MPs+hpD6ev4yjGpcuPaLODyFNbiKQQvdXCTpWqCVv T4uF4eN7RnwRlrsAVk6dkbm7E0W4hZ9mp4+bvWKYPPUb3CNLzrpy4UOUw+SmZ8KlX+WJ Hc5g== X-Gm-Message-State: ANoB5plscNi/Pfpp9s9EsHJDdrBlnyVqLakVF5TFcUTlsCJtps7PjXEc dJB9TJduOOTr1em6pUR4GZMnmncVkoRcSFElN1c= X-Google-Smtp-Source: AA0mqf7Eor56JkLWMp3BkBkzbFgk0ApoO1wJTfelPIdMNLRp7vtoQfG92DhbrquAVl6P+4UX6DuSvu8Nm2TCLoxe9tc= X-Received: by 2002:aa7:c84e:0:b0:470:219a:bf31 with SMTP id g14-20020aa7c84e000000b00470219abf31mr1091593edt.163.1671087655267; Wed, 14 Dec 2022 23:00:55 -0800 (PST) In-Reply-To: <87359h8968.fsf@web.de> Received-SPF: pass client-ip=2a00:1450:4864:20::536; envelope-from=lekktu@gmail.com; helo=mail-ed1-x536.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_NONE=-0.0001, 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: 2.1.29 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-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.devel:301440 Archived-At: --00000000000014b27105efd86a25 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Thu, Dec 15, 2022 at 7:37 AM Dr. Arne Babenhauserheide wrote: > Is this guaranteed or just an implementation detail? That depends on how you interpret it. IIRC, that all "" are the same object was done to avoid having tons of "" in pure space. So in that sense, is guaranteed. And, as such, the warning is superfluous in this specific case. Anyway, as documented, that identical constant strings are different objects is, in general, an implementation detail, and the same goes for floats: *Emacs Lisp Reference, 2.8 Equality Predicates* (eq 3.0 3.0) =E2=87=92 t or nil ;; Equal floats may or may not be the same object. (eq "asdf" "asdf") =E2=87=92 t or nil ;; Equal string constants or may not be the same object. --00000000000014b27105efd86a25 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable


<= div dir=3D"ltr" class=3D"gmail_attr">On Thu, Dec 15, 2022 at 7:37 AM Dr. Ar= ne Babenhauserheide <arne_bab@web.de<= /a>> wrote:

> Is this guaranteed or just an implementat= ion detail?

That depends on how you interpret it. IIRC, that all "" are t= he same object was done to avoid having tons of "" in pure space.= So in that sense, is guaranteed. And, as such, the warning is superfluous = in this specific case.

Anywa= y, as documented, that identical constant strings are different objects is,= in general, an implementation detail, and the same goes for floats:=

Emacs Lisp Reference, 2.8 Equal= ity Predicates

=C2=A0 =C2=A0 =C2= =A0 =C2=A0 =C2=A0 (eq 3.0 3.0)
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0= =C2=A0 =C2=A0=E2=87=92 t or nil
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 ;; E= qual floats may or may not be the same object.

=C2=A0 =C2=A0 =C2=A0 = =C2=A0 =C2=A0 (eq "asdf" "asdf")
=C2=A0 =C2=A0 =C2= =A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0=E2=87=92 t or nil
=C2=A0 =C2=A0 = =C2=A0 =C2=A0 =C2=A0 ;; Equal string constants or may not be the same objec= t.

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