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.bugs Subject: bug#42147: 28.0.50; pure vs side-effect-free, missing optimizations? Date: Sat, 25 Jul 2020 17:09:42 -0400 Message-ID: References: <3A9CC2A3-8307-47B2-8D80-795C0AF020E1@acm.org> <0433A879-C98D-4B1A-B85C-A15DA9289099@acm.org> <1621669100.2102667.1593639091621@mail.yahoo.com> <33C2E2C8-16A6-47A9-B3A4-8A5F43648E04@acm.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="5836"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.0.50 (gnu/linux) Cc: Mattias =?UTF-8?Q?Engdeg=C3=A5rd?= , Paul Eggert , Andrea Corallo , 42147@debbugs.gnu.org To: Philipp Stephani Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Sat Jul 25 23:10:11 2020 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 1jzRQp-0001QP-0v for geb-bug-gnu-emacs@m.gmane-mx.org; Sat, 25 Jul 2020 23:10:11 +0200 Original-Received: from localhost ([::1]:44174 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jzRQn-0001m7-JB for geb-bug-gnu-emacs@m.gmane-mx.org; Sat, 25 Jul 2020 17:10:09 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:58102) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jzRQh-0001lz-37 for bug-gnu-emacs@gnu.org; Sat, 25 Jul 2020 17:10:03 -0400 Original-Received: from debbugs.gnu.org ([209.51.188.43]:39712) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jzRQg-00067V-Oz for bug-gnu-emacs@gnu.org; Sat, 25 Jul 2020 17:10:02 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1jzRQg-0003mH-ID for bug-gnu-emacs@gnu.org; Sat, 25 Jul 2020 17:10:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Stefan Monnier Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Sat, 25 Jul 2020 21:10:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 42147 X-GNU-PR-Package: emacs Original-Received: via spool by 42147-submit@debbugs.gnu.org id=B42147.159571139314501 (code B ref 42147); Sat, 25 Jul 2020 21:10:02 +0000 Original-Received: (at 42147) by debbugs.gnu.org; 25 Jul 2020 21:09:53 +0000 Original-Received: from localhost ([127.0.0.1]:51258 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1jzRQW-0003lp-Mn for submit@debbugs.gnu.org; Sat, 25 Jul 2020 17:09:52 -0400 Original-Received: from mailscanner.iro.umontreal.ca ([132.204.25.50]:13805) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1jzRQU-0003lc-Vt for 42147@debbugs.gnu.org; Sat, 25 Jul 2020 17:09:51 -0400 Original-Received: from pmg1.iro.umontreal.ca (localhost.localdomain [127.0.0.1]) by pmg1.iro.umontreal.ca (Proxmox) with ESMTP id 63BD01002D8; Sat, 25 Jul 2020 17:09:45 -0400 (EDT) Original-Received: from mail01.iro.umontreal.ca (unknown [172.31.2.1]) by pmg1.iro.umontreal.ca (Proxmox) with ESMTP id D7DB01002AC; Sat, 25 Jul 2020 17:09:43 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=iro.umontreal.ca; s=mail; t=1595711383; bh=ROY+2BZoVdRPXoLPb5T9xoBD9ghEnI+j5tGRsroVBhI=; h=From:To:Cc:Subject:References:Date:In-Reply-To:From; b=i5lZ2XTdjC9OQJ/pI1DIcExm4fGkRjKVDjbtvntKnGoJyONdg4fYiapxibn3S0nrO ou7ptq+bRPObidE7brIK4khsT02j1RvL+ysaWmIWaR5f8QQO/Lz3AM7FzGrBw/yJof +Y4E0l15dg3arkU5yJ81SpUZ1ToGt4ksZy6BvV9aLscrMta+Xe6wyXeCEGK8OH0Ps/ 03tYRy2IBeMjL8VurYRNro0u4zeE0y2bhQmG0QZuc0bcntVe3xuXyz9VrIFm2V0b+f i9hYH8/LJiYpcFLhpx1+sbFndBhXU5AsXe36PyuTxalFnwfs5FADDG6iLbOQHoXBXD K2lo5Dl9vNW+g== Original-Received: from milanesa (unknown [104.247.229.155]) by mail01.iro.umontreal.ca (Postfix) with ESMTPSA id 70CE412059A; Sat, 25 Jul 2020 17:09:43 -0400 (EDT) In-Reply-To: (Philipp Stephani's message of "Sat, 25 Jul 2020 22:11:52 +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:183552 Archived-At: > I don't think we can really do that, as that would allow the byte > compiler to introduce bugs in the code, right? The manual states that > "This function [concat] always constructs a new string that is not > =E2=80=98eq=E2=80=99 to any existing string" so I don't see how it could = ever be pure. And yet, `concat` has been marked as "pure" even before we introduced the notion of pure. More specifically, the code in byte-opt.el which optimizes calls to pure functions was originally written exclusively for `concat`: commit 79d137ffe7dac5fe3041b4916c715f4ce91143af Author: Karl Heuer Date: Mon Nov 3 03:58:23 1997 +0000 =20=20=20=20 (byte-optimize-concat): New function. followed by: commit e856a453a1c1ce1907b3b582841bce3e9cff8cec Author: Stefan Monnier Date: Mon Mar 22 15:21:08 2004 +0000 =20=20=20=20 (byte-compile-log-lap, byte-compile-inline-expand): Use backquote. (byte-optimize-pure-func): Rename from byte-optimize-concat. (symbol-name, regexp-opt, regexp-quote): Mark as pure. -- Stefan