From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Stefan Monnier via Users list for the GNU Emacs text editor Newsgroups: gmane.emacs.help Subject: Re: Using comment characters for specific major modes Date: Sat, 05 Jun 2021 23:24:13 -0400 Message-ID: References: Reply-To: Stefan Monnier 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="37052"; 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:M2818Re2Ms0YeVD1s+RBDbHk1to= Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Sun Jun 06 05:24:41 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 1lpjOz-0009TO-84 for geh-help-gnu-emacs@m.gmane-mx.org; Sun, 06 Jun 2021 05:24:41 +0200 Original-Received: from localhost ([::1]:41376 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lpjOy-0003vY-Am for geh-help-gnu-emacs@m.gmane-mx.org; Sat, 05 Jun 2021 23:24:40 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:53386) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lpjOg-0003vP-6P for help-gnu-emacs@gnu.org; Sat, 05 Jun 2021 23:24:22 -0400 Original-Received: from ciao.gmane.io ([116.202.254.214]:41956) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lpjOe-0004XI-Ef for help-gnu-emacs@gnu.org; Sat, 05 Jun 2021 23:24:21 -0400 Original-Received: from list by ciao.gmane.io with local (Exim 4.92) (envelope-from ) id 1lpjOb-0008tK-Qf for help-gnu-emacs@gnu.org; Sun, 06 Jun 2021 05:24:17 +0200 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:130572 Archived-At: > That uses the command (comment-dwim ARG), but I got to get the comment characters > to append to the string "s". > >   (setq-local s (concat ";; " (make-string lena ?\;))) > > At least that was my plan.  You may know the proper way to do it though. Here's how you could go about finding the answer: Seeing that `comment-dwim` manages to find the ";;" you're looking for, you could look into it code: `C-h o comment-dwim RET` then click on the link to jump to the definition. There you'll see: [...] (comment-normalize-vars) (if (use-region-p) (comment-or-uncomment-region (region-beginning) (region-end) arg) (if (save-excursion (beginning-of-line) (not (looking-at "\\s-*$"))) ;; FIXME: If there's no comment to kill on this line and ARG is ;; specified, calling comment-kill is not very clever. (if arg (comment-kill (and (integerp arg) arg)) (comment-indent)) ;; Inserting a comment on a blank line. comment-indent calls ;; c-i-c-f if needed in the non-blank case. (if comment-insert-comment-function (funcall comment-insert-comment-function) (let ((add (comment-add arg))) ;; Some modes insist on keeping column 0 comment in column 0 ;; so we need to move away from it before inserting the comment. (indent-according-to-mode) (insert (comment-padright comment-start add)) (save-excursion (unless (string= "" comment-end) (insert (comment-padleft comment-end add))) (indent-according-to-mode))))))) And here you already see some functions and variable which might give you some answers, such as `comment-add`, `comment-insert-comment-function`, `comment-start`, ... Using `C-h o` on those should fairly quickly lead you to: comment-start is a variable defined in ‘newcomment.el’. Its value is ";" Local in buffer newcomment.el.gz; global value is nil This variable is safe as a file local variable if its value satisfies the predicate ‘string-or-null-p’. Probably introduced at or before Emacs version 21.1. Documentation: String to insert to start a new comment, or nil if no comment syntax. [back] -- Stefan