From mboxrd@z Thu Jan  1 00:00:00 1970
Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail
From: Philip Kaludercic <philipk@posteo.net>
Newsgroups: gmane.emacs.devel
Subject: Re: cond* vs pcase
Date: Tue, 06 Feb 2024 18:57:43 +0000
Message-ID: <87o7cts9nc.fsf@posteo.net>
References: <DU2PR02MB10109F1CBA5F7A8D78A597A5D96472@DU2PR02MB10109.eurprd02.prod.outlook.com>
 <E1rX1UK-0005Ip-Ff@fencepost.gnu.org> <87il32iwmm.fsf@posteo.net>
 <E1rXO89-0003Ll-3B@fencepost.gnu.org> <87o7cttu4l.fsf@posteo.net>
 <E1rXPEL-0000nD-Iw@fencepost.gnu.org>
Mime-Version: 1.0
Content-Type: text/plain
Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214";
	logging-data="8371"; mail-complaints-to="usenet@ciao.gmane.io"
Cc: arthur.miller@live.com,  emacs-devel@gnu.org
To: "Alfred M. Szmidt" <ams@gnu.org>
Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Tue Feb 06 19:58:32 2024
Return-path: <emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org>
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 <emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org>)
	id 1rXQeN-0001xH-IR
	for ged-emacs-devel@m.gmane-mx.org; Tue, 06 Feb 2024 19:58:31 +0100
Original-Received: from localhost ([::1] helo=lists1p.gnu.org)
	by lists.gnu.org with esmtp (Exim 4.90_1)
	(envelope-from <emacs-devel-bounces@gnu.org>)
	id 1rXQdh-00055r-06; Tue, 06 Feb 2024 13:57:49 -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 <philipk@posteo.net>)
 id 1rXQdf-00055U-Ly
 for emacs-devel@gnu.org; Tue, 06 Feb 2024 13:57:47 -0500
Original-Received: from mout02.posteo.de ([185.67.36.66])
 by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256)
 (Exim 4.90_1) (envelope-from <philipk@posteo.net>)
 id 1rXQde-0007Ms-4V
 for emacs-devel@gnu.org; Tue, 06 Feb 2024 13:57:47 -0500
Original-Received: from submission (posteo.de [185.67.36.169]) 
 by mout02.posteo.de (Postfix) with ESMTPS id 6423F240101
 for <emacs-devel@gnu.org>; Tue,  6 Feb 2024 19:57:44 +0100 (CET)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=posteo.net; s=2017;
 t=1707245864; bh=UTSpoUiM/BkgKLzNklAVoembmA4d2rfCWokFHPZ7spI=;
 h=From:To:Cc:Subject:Autocrypt:OpenPGP:Date:Message-ID:MIME-Version:
 Content-Type:From;
 b=sHOOcBkkh81Ab/E0apUILBNqaqECV6xMP96XC/4TczKfXvl3eA38skbRrPg2JwONl
 wkS83WoTAIZXuNTnIZbSgz+S1aPzr2HPbGZfhkCqEcWuJXG7A+Ynk4DZsACWgkKvzU
 Ft/rPqXAQXQTX+6mJed6QgwYwO4TBw3Vqthueg/CLpwN0xt/XtAkEU3hmtxhPeX8FZ
 NM61lQoG9Gsf16ahLyqekUTr4248uWEwnCFjn60fVlwPfFwIqnZ2+66SR16xeHFqIu
 ei90MfEF8Y81XfrSdV23gOEwoYgawUlybXZ8fJdzIC/rrnpgX6ufaCas0drGZtSS9c
 hmpZxI3YhOqmQ==
Original-Received: from customer (localhost [127.0.0.1])
 by submission (posteo.de) with ESMTPSA id 4TTsvC5QtHz6txf;
 Tue,  6 Feb 2024 19:57:43 +0100 (CET)
In-Reply-To: <E1rXPEL-0000nD-Iw@fencepost.gnu.org> (Alfred M. Szmidt's message
 of "Tue, 06 Feb 2024 12:27:33 -0500")
Autocrypt: addr=philipk@posteo.net; keydata=
 mDMEZBBQQhYJKwYBBAHaRw8BAQdAHJuofBrfqFh12uQu0Yi7mrl525F28eTmwUDflFNmdui0QlBo
 aWxpcCBLYWx1ZGVyY2ljIChnZW5lcmF0ZWQgYnkgYXV0b2NyeXB0LmVsKSA8cGhpbGlwa0Bwb3N0
 ZW8ubmV0PoiWBBMWCAA+FiEEDg7HY17ghYlni8XN8xYDWXahwukFAmQQUEICGwMFCQHhM4AFCwkI
 BwIGFQoJCAsCBBYCAwECHgECF4AACgkQ8xYDWXahwulikAEA77hloUiSrXgFkUVJhlKBpLCHUjA0
 mWZ9j9w5d08+jVwBAK6c4iGP7j+/PhbkxaEKa4V3MzIl7zJkcNNjHCXmvFcEuDgEZBBQQhIKKwYB
 BAGXVQEFAQEHQI5NLiLRjZy3OfSt1dhCmFyn+fN/QKELUYQetiaoe+MMAwEIB4h+BBgWCAAmFiEE
 Dg7HY17ghYlni8XN8xYDWXahwukFAmQQUEICGwwFCQHhM4AACgkQ8xYDWXahwukm+wEA8cml4JpK
 NeAu65rg+auKrPOP6TP/4YWRCTIvuYDm0joBALw98AMz7/qMHvSCeU/hw9PL6u6R2EScxtpKnWof
 z4oM
OpenPGP: id=7126E1DE2F0CE35C770BED01F2C3CC513DB89F66;
 url="https://keys.openpgp.org/vks/v1/by-fingerprint/7126E1DE2F0CE35C770BED01F2C3CC513DB89F66";
 preference=signencrypt
Received-SPF: pass client-ip=185.67.36.66; envelope-from=philipk@posteo.net;
 helo=mout02.posteo.de
X-Spam_score_int: -43
X-Spam_score: -4.4
X-Spam_bar: ----
X-Spam_report: (-4.4 / 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,
 RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001,
 SPF_HELO_NONE=0.001, SPF_PASS=-0.001,
 T_SCC_BODY_TEXT_LINE=-0.01 autolearn=unavailable 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." <emacs-devel.gnu.org>
List-Unsubscribe: <https://lists.gnu.org/mailman/options/emacs-devel>,
 <mailto:emacs-devel-request@gnu.org?subject=unsubscribe>
List-Archive: <https://lists.gnu.org/archive/html/emacs-devel>
List-Post: <mailto:emacs-devel@gnu.org>
List-Help: <mailto:emacs-devel-request@gnu.org?subject=help>
List-Subscribe: <https://lists.gnu.org/mailman/listinfo/emacs-devel>,
 <mailto:emacs-devel-request@gnu.org?subject=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:315942
Archived-At: <http://permalink.gmane.org/gmane.emacs.devel/315942>

"Alfred M. Szmidt" <ams@gnu.org> writes:

>    > Because your not doing pattern matching, you're comparing against a
>    > set of strings/symbols/numbers/....
>
>    Simply because pattern matching is a more powerful generalisation,
>    capable of expressing case-distinction; in the end it compiles down to
>    almost the same code anyway.
>
> Are you suggesting that COND/CASE/... and other "trivial" matching
> constructs should be replaced with PCASE/COND*?

No, just that using pcase in these cases isn't wrong.

Drew Adams <drew.adams@oracle.com> writes:

>> Simply because [1] pattern matching is a more
>> powerful generalisation, capable of expressing
>> case-distinction; [2] in the end it compiles
>> down to almost the same code anyway.
>
> Wow.  Really _not_ a good reason (IMHO).
> Neither of those reasons [1,2] is good.
>
> With that reasoning you'll use `pcase'
> _always and everywhere_ - never `if',
> `cond', `let', `or', `and',...

Please don't be dishonest; My question was why cl-case was more
appropriate than pcase, where both are macros that boil down to simpler
primitives.  I don't see an inherent advantage to using the more
specific abstraction over the more generic one.  I like pcase, and
prefer using it in my code, but if you've got some code that is already
using a lot of cl-lib and no pcase, then there is no point in transiting
cl-case forms into pcase.

>
> Hey, `pcase' can do it all!  And it
> compiles down to almost the same thing!
>
> "Demain on rase gratis !"