From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Heime Newsgroups: gmane.emacs.help Subject: Re: Functions with multiple optional arguments Date: Mon, 17 Oct 2022 05:42:53 +0000 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="17512"; mail-complaints-to="usenet@ciao.gmane.io" Cc: "help-gnu-emacs@gnu.org" To: Jean Louis Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Mon Oct 17 07:47:42 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 1okIyT-0004Ow-VS for geh-help-gnu-emacs@m.gmane-mx.org; Mon, 17 Oct 2022 07:47:42 +0200 Original-Received: from localhost ([::1]:53410 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1okIyS-0000tM-Dy for geh-help-gnu-emacs@m.gmane-mx.org; Mon, 17 Oct 2022 01:47:40 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:55996) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1okIu8-0000p6-CU for help-gnu-emacs@gnu.org; Mon, 17 Oct 2022 01:43:24 -0400 Original-Received: from mail-4318.protonmail.ch ([185.70.43.18]:24135) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1okIu4-0001Fs-UJ for help-gnu-emacs@gnu.org; Mon, 17 Oct 2022 01:43:10 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=protonmail.com; s=protonmail3; t=1665985382; x=1666244582; bh=GmJcTmD+ihHLuOS0lDiPVjs6E+8vl/ruC/+W6u4/Omo=; h=Date:To:From:Cc:Subject:Message-ID:In-Reply-To:References: Feedback-ID:From:To:Cc:Date:Subject:Reply-To:Feedback-ID: Message-ID; b=ljHmSvidqTG+ZxRcgE4gxhB/S0xT5Qk235d47OeQ73TpLjKC1suD92kW2yt8SmVSD 5BvG5GJtLmc56Ns6avBAYZthIflV3UsDlpk0tBviCRCUCwpx7JRriWw0RYZaTs4sD7 r0gvT9Vh96f2EkasJys4HO4nVKH5rNH76DJ1oZJ5H97ZBruy+hb+6WZdISPSH16PmT pJFGXbV+QvtG3g6EEI+3vqKDTMiOlUuJvxWpmybTZ1jpPeLLtD6oTLwQ0IPX/4m+tX RVEs4iF0XDbRQJn2QQokb8C05VrbSAukntHyVfGKRDMDwVuJnQC18JQdFuAuQCdWKV NLgkNBpvFmSgg== In-Reply-To: Feedback-ID: 57735886:user:proton Received-SPF: pass client-ip=185.70.43.18; envelope-from=heimeborgia@protonmail.com; helo=mail-4318.protonmail.ch X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham 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:140067 Archived-At: ------- Original Message ------- On Monday, October 17th, 2022 at 4:05 AM, Jean Louis wro= te: > * Heime via Users list for the GNU Emacs text editor help-gnu-emacs@gnu.o= rg [2022-10-17 00:06]: >=20 > > Have been writing a function that has two optional arguments. It is > > turning out to be a difficult task in situations when one in missing > > an argument. Anybody has experience about this, as I have not seen > > much code with multiple optional arguments. >=20 >=20 > If argument is optional but required by your function, I use this method: >=20 > (defun my-fun (&optional title description) > (let ((title (or title "Best Movie")) > (description (or description "Description"))) > (message "%s: %s" title description))) >=20 > (my-fun) I see that the trick is to assign defaults that way. I like it, very cleve= r.