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: Code for cond* Date: Sun, 25 Feb 2024 13:13:38 -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="3998"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Cc: Alan Mackenzie , rms@gnu.org, emacs-devel@gnu.org To: "Alfred M. Szmidt" Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Sun Feb 25 19:14:43 2024 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 1reJ1O-0000uF-Ez for ged-emacs-devel@m.gmane-mx.org; Sun, 25 Feb 2024 19:14:42 +0100 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1reJ0d-0002pI-8U; Sun, 25 Feb 2024 13:13:56 -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 1reJ0T-0002oe-9g for emacs-devel@gnu.org; Sun, 25 Feb 2024 13:13:45 -0500 Original-Received: from mailscanner.iro.umontreal.ca ([132.204.25.50]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1reJ0R-0004uo-Cq; Sun, 25 Feb 2024 13:13:45 -0500 Original-Received: from pmg3.iro.umontreal.ca (localhost [127.0.0.1]) by pmg3.iro.umontreal.ca (Proxmox) with ESMTP id 2A2A4441650; Sun, 25 Feb 2024 13:13:41 -0500 (EST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=iro.umontreal.ca; s=mail; t=1708884819; bh=WtVhaZVxCbIL3004XPpoQCQNXimlIfRzjQdm65mMWu4=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=AnFRcyAFJ/QTRBa+SConP/xeD5ClQIh/6E8T2PgCDAy9bvbLmzaRlzb3+X8JqC3Yu /HGtrY7LSTO+viQDkCiPig0IBVMGA9Oj6fpXDXuTDT6kbHExKhMwIaskDMAf6k0Vym e8rssTAU+5P+Lk7i+xv4CsoaEcpSSUPVxtpyJTquTvkqFt5WZx3HilQ8zF9tiPQHpl wUV+Sfjt0Wbab5PwnGbGxvaFQt7XurpvcE3UtmzqffN0evHbv0KhqkaCR/CXCedVV2 PrfXFyHr1HOA5bBh3zsc+bvJrkv5V03PAixRndkxJBjstiaruAaU2n3EhUSEztlq4k uy8w2EZLz6Oxg== Original-Received: from mail01.iro.umontreal.ca (unknown [172.31.2.1]) by pmg3.iro.umontreal.ca (Proxmox) with ESMTP id BB5DC441D73; Sun, 25 Feb 2024 13:13:39 -0500 (EST) Original-Received: from alfajor (unknown [45.72.205.238]) by mail01.iro.umontreal.ca (Postfix) with ESMTPSA id 89FA612030C; Sun, 25 Feb 2024 13:13:39 -0500 (EST) In-Reply-To: (Alfred M. Szmidt's message of "Sun, 25 Feb 2024 12:46:05 -0500") Received-SPF: pass client-ip=132.204.25.50; envelope-from=monnier@iro.umontreal.ca; helo=mailscanner.iro.umontreal.ca X-Spam_score_int: -42 X-Spam_score: -4.3 X-Spam_bar: ---- X-Spam_report: (-4.3 / 5.0 requ) BAYES_00=-1.9, 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, T_SCC_BODY_TEXT_LINE=-0.01 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:316538 Archived-At: > > FWIW, I'm opposed to adding it without first unifying the Pcase and > > `match*` pattern languages (including making sure that third party > > packages which define their own patterns don't need to define them > > separately for `pcase` and for `match*`). > > > [ It's trivial to do by making `match*` reuse the Pcase machinery, so > > there is no serious obstacle for that. ] > > I hope that cond* won't be written on top of pcase. [ Side note: my comment above specifically refers to `match*`, not to `cond*`. Let's not confuse the two: `cond*` is an actual addition, whereas `match*` mostly reinvents Pcase patterns, with a few tweaks to some of its syntax. ] I don't have a strong opinion on that, actually. I hope that we don't end up having to maintain two implementations of the pattern matching code, but there can be good arguments for such a duplication (there are several different implementation strategies, each with their own advantages), so if that's what it takes, I'm OK with it. > and maybe even that that pcase could be rewritten using cond*. As already mentioned in this long thread, the current `match*` implementation does not generate good enough code for existing `pcase` uses (and fixing that probably requires non-trivial changes). Stefan