From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.devel Subject: Re: cc-mode: Make all parameters introduced in Emacs 26 optional Date: Mon, 12 Mar 2018 18:40:53 -0400 Message-ID: References: <1516608561.1943450.1243462056.1A47A60F@webmail.messagingengine.com> <20180122203254.GA4888@ACM> <1520885798.1440538.1300560400.68951242@webmail.messagingengine.com> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: blaine.gmane.org 1520894404 726 195.159.176.226 (12 Mar 2018 22:40:04 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Mon, 12 Mar 2018 22:40:04 +0000 (UTC) User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.0.50 (gnu/linux) To: emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Mon Mar 12 23:40:00 2018 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1evW6n-0008Rb-S8 for ged-emacs-devel@m.gmane.org; Mon, 12 Mar 2018 23:39:57 +0100 Original-Received: from localhost ([::1]:36007 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1evW8q-0000YZ-T5 for ged-emacs-devel@m.gmane.org; Mon, 12 Mar 2018 18:42:04 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:37466) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1evW7s-0000W7-LS for emacs-devel@gnu.org; Mon, 12 Mar 2018 18:41:05 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1evW7p-0005uA-B2 for emacs-devel@gnu.org; Mon, 12 Mar 2018 18:41:04 -0400 Original-Received: from [195.159.176.226] (port=59862 helo=blaine.gmane.org) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1evW7p-0005tF-3f for emacs-devel@gnu.org; Mon, 12 Mar 2018 18:41:01 -0400 Original-Received: from list by blaine.gmane.org with local (Exim 4.84_2) (envelope-from ) id 1evW5j-00075a-SD for emacs-devel@gnu.org; Mon, 12 Mar 2018 23:38:51 +0100 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 12 Original-X-Complaints-To: usenet@blaine.gmane.org Cancel-Lock: sha1:mz6GPErVauyCvMepFXcDE+mUyGo= X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 195.159.176.226 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.org gmane.emacs.devel:223667 Archived-At: > Is there any way for package to know how many mandatory arguments a > function has, to be able to branch out for compatibility reasons? The way I recommend is: (condition-case nil (call1 ...) (wrong-number-of-arguments (call2 ...))) -- Stefan