From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Jean Louis Newsgroups: gmane.emacs.help Subject: Re: Surprising behaviour of 'append' with strings Date: Sun, 6 Nov 2022 15:39:16 +0300 Message-ID: References: <6554cc02-2082-3dca-73cc-05fee1c6c4d0.ref@yahoo.de> <6554cc02-2082-3dca-73cc-05fee1c6c4d0@yahoo.de> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="32742"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Mutt/2.2.7+37 (a90f69b) (2022-09-02) Cc: help-gnu-emacs@gnu.org To: "R. Diez" Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Sun Nov 06 13:39:52 2022 Return-path: Envelope-to: geh-help-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 1orewK-0008MX-Oy for geh-help-gnu-emacs@m.gmane-mx.org; Sun, 06 Nov 2022 13:39:52 +0100 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1orew8-0002Uw-Ml; Sun, 06 Nov 2022 07:39:41 -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 1orew6-0002UV-JN for help-gnu-emacs@gnu.org; Sun, 06 Nov 2022 07:39:38 -0500 Original-Received: from stw1.rcdrun.com ([217.170.207.13]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1orew2-0007hj-Az for help-gnu-emacs@gnu.org; Sun, 06 Nov 2022 07:39:38 -0500 Original-Received: from localhost ([::ffff:197.239.4.221]) (AUTH: PLAIN admin, TLS: TLS1.3,256bits,ECDHE_RSA_AES_256_GCM_SHA384) by stw1.rcdrun.com with ESMTPSA id 0000000000081FA6.000000006367AB02.00005FFD; Sun, 06 Nov 2022 05:39:30 -0700 Mail-Followup-To: "R. Diez" , help-gnu-emacs@gnu.org Content-Disposition: inline In-Reply-To: <6554cc02-2082-3dca-73cc-05fee1c6c4d0@yahoo.de> Received-SPF: pass client-ip=217.170.207.13; envelope-from=bugs@gnu.support; helo=stw1.rcdrun.com X-Spam_score_int: -17 X-Spam_score: -1.8 X-Spam_bar: - X-Spam_report: (-1.8 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_SBL=0.141, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Users list for the GNU Emacs text editor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: "help-gnu-emacs" Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.help:140721 Archived-At: Hello, * R. Diez [2022-11-06 14:07]: > I want to build a list of command-line arguments to run a > program. Each element of the list must be a string. First I was using function `shell-command' which is pretty liberate, and it invokes shell and string as command, but that one is in reality error prone and difficult, especially when there is quoting required. > The commands are complex shell invocations with nested shell > commands. I have been shell-quoting and concatenating plain strings > for a long time, but it is error prone (in my experience). You should use `call-process' (call-process PROGRAM &optional INFILE DESTINATION DISPLAY &rest ARGS) Probably introduced at or before Emacs version 18. Then look ARGS, that is where you place the list. > So now I am testing a different approach: I am building a list of > strings, joining them with (string-join my-cmd-args " "), and > passing the result to 'compile'. I guess that could be all thinking in wrong direction, look at `call-process' first and tell us if you tried that one out. It minimizes all errors. > (append "1") ⇒ "1" > (append "1" "2") ⇒ (49 . "2") Right > (my-append > "1" > (list "2" "3") > "4" > ) > > The result should be: > ("1" "2" "3" "4") `append' is to append for example lists: (append (list 1) (list 2 3 4)) ⇒ (1 2 3 4) (append (list "1") (list "2" "3" "4")) ⇒ ("1" "2" "3" "4") -- Jean Take action in Free Software Foundation campaigns: https://www.fsf.org/campaigns In support of Richard M. Stallman https://stallmansupport.org/