From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Emanuel Berg Newsgroups: gmane.emacs.help Subject: Re: Executing function only if another function is defined Date: Mon, 25 Jul 2022 03:39:25 +0200 Message-ID: <87czduhsxe.fsf@dataswamp.org> References: Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="14203"; 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:y/hYaCu4jw3F86ynvtkhjISBRBE= Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Mon Jul 25 03:40:16 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 1oFn4y-0003TD-Fj for geh-help-gnu-emacs@m.gmane-mx.org; Mon, 25 Jul 2022 03:40:16 +0200 Original-Received: from localhost ([::1]:47328 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1oFn4w-00052s-AE for geh-help-gnu-emacs@m.gmane-mx.org; Sun, 24 Jul 2022 21:40:14 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:55610) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oFn4M-00052T-7C for help-gnu-emacs@gnu.org; Sun, 24 Jul 2022 21:39:38 -0400 Original-Received: from ciao.gmane.io ([116.202.254.214]:41934) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oFn4K-0004D9-5E for help-gnu-emacs@gnu.org; Sun, 24 Jul 2022 21:39:37 -0400 Original-Received: from list by ciao.gmane.io with local (Exim 4.92) (envelope-from ) id 1oFn4H-0002ie-V7 for help-gnu-emacs@gnu.org; Mon, 25 Jul 2022 03:39:33 +0200 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=0.249, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 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:138602 Archived-At: carlmarcos--- via Users list for the GNU Emacs text editor wrote: > Because it may be possible that some functions are not > available (e.g. during testing or debugging phases), I would > like to test whether the function `toucan' has been defined > before I call `docboost'. What can I do? > > (defun toucan-usage () > "TODO" > > (docboost 'toucan "Usage Information")) (Why are you using no-break space?) What you can do? You can ... 1. `require' the library where "toucan" is defined. 2. Use the hash/sharp-quote, #', instead of just the quote for toucan. (#' is `function' and ' is `quote' BTW.) 3. Byte-compile. The byte compiler will tell you if toucan is undefined. -- underground experts united https://dataswamp.org/~incal