From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: Instead of pcase Date: Mon, 04 Dec 2023 13:58:07 +0200 Message-ID: <83zfyq5gds.fsf@gnu.org> References: <87fs169mjj.fsf@posteo.net> <093f11a1-57c2-5e56-d39b-26fef1c67cbb@gutov.dev> <25942.25061.217864.329049@retriever.mtv.corp.google.com> <87zfzdcz6z.fsf@posteo.net> <763f067b-4ca9-1eba-9f3c-424c38589e9c@gutov.dev> <83fs0navpj.fsf@gnu.org> <838r6ebfhw.fsf@gnu.org> <83zfyu9wdg.fsf@gnu.org> <87edg69tup.fsf@linux-m68k.org> Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="21442"; mail-complaints-to="usenet@ciao.gmane.io" Cc: schwab@linux-m68k.org, emacs-devel@gnu.org To: rms@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Mon Dec 04 12:59:10 2023 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 1rA7bR-0005IR-Q3 for ged-emacs-devel@m.gmane-mx.org; Mon, 04 Dec 2023 12:59:09 +0100 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rA7aV-0006BF-Ox; Mon, 04 Dec 2023 06:58:11 -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 1rA7aT-0006Ag-HK for emacs-devel@gnu.org; Mon, 04 Dec 2023 06:58:09 -0500 Original-Received: from fencepost.gnu.org ([2001:470:142:3::e]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rA7aS-0004RO-JQ; Mon, 04 Dec 2023 06:58:08 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=gnu.org; s=fencepost-gnu-org; h=References:Subject:In-Reply-To:To:From:Date: mime-version; bh=JFslfuLjBkYIBnqt51DDFmQOEpnDqalwraZR6EAe64E=; b=ltHqruadJO7V pQd+HEUi1Q09+WnxDhD0VIN5i18i2XgECrIX+MK6LPcC0JR0BD840nQoHskyR9uD+LDorH4XUuzBP Lkm3kKJLUh148HrLYGAL3wV/0oUlfpKmJg7XG5r9Tk1d0CLW1nccfQ2haIFGvOSFOPUu/meFxvXF0 FryM9DXwE8pdamCJy1ytCjOZ/arQgUA0si7ORYaH6pek4bRaZya0hXt+zzv58PCJpJyKjAhXi/9f6 dy3cetq4j2uJNS2DKOmmYzrVaXpQWOqjAmhOcBeuqCtgw41MamxirBCFVNwETI1Klw8UQ9TdEBwJv YesyndpKfBW/mc/WikhTAg==; In-Reply-To: (message from Richard Stallman on Sun, 03 Dec 2023 22:08:21 -0500) 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:313515 Archived-At: > From: Richard Stallman > Cc: emacs-devel@gnu.org > Date: Sun, 03 Dec 2023 22:08:21 -0500 > > > This is not true. There is no magic at all in the use of this reader > > feature which is totally lost after reading. It is absolutely > > impossible to detect its use afterwards. > > As a factual matter about dotted pairs in pcase patterns, that is > correct. > > However, we have repeatedly seen that experienced Lispers, who would > have no trouble understanding those constructs in a backquote meant to > actually construct a structure of conses, don't know what to make of > them on encountering them in pcase patterns. > > That's another factual matter about dotted pairs in pcase patterns. > It is more a psychological matter than a computational matter, but > that doesn't invalidate the observation. > > It is part of the impact of complexity of pcase. Some people are saying that everything is clear because the Lisp reader does this and that. But when humans read code, they don't normally run the Lisp reader in their head, they use other techniques to read and grasp what the code does. If there's a need to ask what does the Lisp reader do with some syntax, that is already an obstacle to understanding the code, even though eventually one can understand it, whether by thinking what the reader does or by actually running the reader and/or macro-expansion.