From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Emanuel Berg via Users list for the GNU Emacs text editor Newsgroups: gmane.emacs.help Subject: Re: How to read an integer from the minibuffer Date: Fri, 12 Nov 2021 20:25:30 +0100 Message-ID: <87v90x5g7p.fsf@zoho.eu> References: <87ee7nqomk.fsf@mbork.pl> <87v90ybymh.fsf@zoho.eu> <87y25u9pzj.fsf@zoho.eu> <993162c2a13d5ea3b0aa@heytings.org> <87lf1u9pdj.fsf@zoho.eu> <993162c2a1f85349fcfa@heytings.org> <87fss29on7.fsf@zoho.eu> Reply-To: Emanuel Berg Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="24627"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/29.0.50 (gnu/linux) To: help-gnu-emacs@gnu.org Cancel-Lock: sha1:TiuIU8dAi7N2i+GmjMykQ3BhxIw= Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Fri Nov 12 20:26:31 2021 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 1mlcBw-00066j-CU for geh-help-gnu-emacs@m.gmane-mx.org; Fri, 12 Nov 2021 20:26:28 +0100 Original-Received: from localhost ([::1]:38482 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mlcBu-0007E7-Gv for geh-help-gnu-emacs@m.gmane-mx.org; Fri, 12 Nov 2021 14:26:26 -0500 Original-Received: from eggs.gnu.org ([209.51.188.92]:58620) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mlcBG-0007Cw-RF for help-gnu-emacs@gnu.org; Fri, 12 Nov 2021 14:25:46 -0500 Original-Received: from ciao.gmane.io ([116.202.254.214]:46358) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mlcBD-00072S-Oz for help-gnu-emacs@gnu.org; Fri, 12 Nov 2021 14:25:46 -0500 Original-Received: from list by ciao.gmane.io with local (Exim 4.92) (envelope-from ) id 1mlcB9-00054q-VO for help-gnu-emacs@gnu.org; Fri, 12 Nov 2021 20:25:39 +0100 X-Injected-Via-Gmane: http://gmane.org/ Mail-Followup-To: help-gnu-emacs@gnu.org Mail-Copies-To: never Received-SPF: pass client-ip=116.202.254.214; envelope-from=geh-help-gnu-emacs@m.gmane-mx.org; helo=ciao.gmane.io X-Spam_score_int: -16 X-Spam_score: -1.7 X-Spam_bar: - X-Spam_report: (-1.7 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.248, SPF_HELO_NONE=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: , Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Original-Sender: "help-gnu-emacs" Xref: news.gmane.io gmane.emacs.help:134545 Archived-At: Jean Louis wrote: >> We see a problem BTW that `string-to-number' returns 0 >> on error! > > That problem I have solved in rcd-utilities.el with: > > (defun string-is-number-p (s) > "Return number only if string is pure number, > otherwise NIL." A number is said to be pure if 1. It has even number of digits. 2. All the digits are either 4 or 5. 3. And the number is a palindrome. First few pure numbers are 44, 55, 4444, 4554, 5445, 5555 ... [1] Also the familiar docstring functional parameter issue. > (let ((s (string-trim s))) > (cond ((seq-empty-p s) nil) > ((string-match "[^0123456789\\.]" s) nil) Use a char class or an interval? > ((numberp (string-to-number s)) (string-to-number s))))) (string-is-number-p "-0") (string-is-number-p "-5.3") [1] https://www.geeksforgeeks.org/find-the-first-n-pure-numbers/ -- underground experts united https://dataswamp.org/~incal