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.help Subject: Re: How to define a (derived) minor mode inaccessible to the user Date: Fri, 22 Jan 2021 09:19:06 -0500 Message-ID: References: <87eeidlfmw.fsf@mbork.pl> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="11588"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.0.50 (gnu/linux) To: help-gnu-emacs@gnu.org Cancel-Lock: sha1:vHlf1NB9faVxu8fx4i98zu1YwQ8= Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Fri Jan 22 15:20:44 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 1l2xIq-0002uk-H0 for geh-help-gnu-emacs@m.gmane-mx.org; Fri, 22 Jan 2021 15:20:44 +0100 Original-Received: from localhost ([::1]:37654 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1l2xIp-0006xu-Iy for geh-help-gnu-emacs@m.gmane-mx.org; Fri, 22 Jan 2021 09:20:43 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:46942) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1l2xHR-0006Uk-Io for help-gnu-emacs@gnu.org; Fri, 22 Jan 2021 09:19:17 -0500 Original-Received: from ciao.gmane.io ([116.202.254.214]:46360) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1l2xHP-0001Sj-Pn for help-gnu-emacs@gnu.org; Fri, 22 Jan 2021 09:19:17 -0500 Original-Received: from list by ciao.gmane.io with local (Exim 4.92) (envelope-from ) id 1l2xHM-00013n-2h for help-gnu-emacs@gnu.org; Fri, 22 Jan 2021 15:19:12 +0100 X-Injected-Via-Gmane: http://gmane.org/ 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=0.249, 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: 2.1.23 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:127317 Archived-At: > I'd like to define a special-purpose major mode, derived from > `special-mode', in such a way that the user cannot set it using M-x. Can you explain why? > (It is to be called via another command.) That doesn't explain why it would be harmful to also expose the actual major mode command. E.g. You can do `M-x comint-mode` even though it likely won't do you much good since `comint-mode` needs to be used together with a process and is hence normally enabled by the command that launches the process. > It seems that `define-derived-mode' always sets the mode as > `interactive'. Indeed. > M-: (symbol-plist 'my--mode) > expecting an `interactive-form' entry on the plist The `interactive-form` property is virtually never used. Instead, the interactive form is traditionally stored within the function. If you *really* care about hiding the major mode from the user I suggest you use an "obscure" or "scary" name. > What's going on? Is it possible to define a (derived) major mode so > that it can't be called interactively? Of course it is: (define-derived-mode my-mode "My" "My doc.") (defconst my-mode (symbol-function 'my-mode)) (fmakunbound 'my-mode) and then you can enable the mode with `(funcall my-mode)`. Stefan