From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: =?UTF-8?Q?Andreas_R=c3=b6hler?= Newsgroups: gmane.emacs.help Subject: Re: (copy-marker nil) Date: Mon, 7 May 2018 19:16:54 +0200 Message-ID: <34886144-0f66-5677-5054-b940cf0f6e76@easy-emacs.de> References: <364c8f2d-06ab-4f81-852f-eb3bac7a0615@easy-emacs.de> <1e55da6a-d791-c613-ac9a-5d9bc57f840f@easy-emacs.de> <0cc6f5df-d980-492c-a6f3-86070a73488c@default> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-Trace: blaine.gmane.org 1525713606 22636 195.159.176.226 (7 May 2018 17:20:06 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Mon, 7 May 2018 17:20:06 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; Linux i686; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 To: Drew Adams , Help Gnu Emacs mailing list Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Mon May 07 19:20:02 2018 Return-path: Envelope-to: geh-help-gnu-emacs@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 1fFjnu-0005np-7z for geh-help-gnu-emacs@m.gmane.org; Mon, 07 May 2018 19:20:02 +0200 Original-Received: from localhost ([::1]:47343 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fFjq1-00031f-EV for geh-help-gnu-emacs@m.gmane.org; Mon, 07 May 2018 13:22:13 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:41626) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fFjjr-0008En-E4 for help-gnu-emacs@gnu.org; Mon, 07 May 2018 13:15:52 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fFjjm-0006ZB-Db for help-gnu-emacs@gnu.org; Mon, 07 May 2018 13:15:51 -0400 Original-Received: from mout.kundenserver.de ([212.227.17.24]:36151) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1fFjjm-0006Yp-3P for help-gnu-emacs@gnu.org; Mon, 07 May 2018 13:15:46 -0400 Original-Received: from [192.168.178.35] ([188.103.18.182]) by mrelayeu.kundenserver.de (mreue101 [212.227.15.183]) with ESMTPSA (Nemesis) id 0M8hqV-1eLJYl2TpL-00wDFO; Mon, 07 May 2018 19:15:40 +0200 In-Reply-To: <0cc6f5df-d980-492c-a6f3-86070a73488c@default> Content-Language: en-US X-Provags-ID: V03:K1:m1LoFNoRmOzc07BVTNi/jg/+PM2hwEuLmIzmRM0Yb+q4pqwtmRo ugqSobEznNVm0iIMu4T1K7fXDrcbfABOC5O4bySLVae4/7VwtfYuc9yFqEN8Gt86LzLkZe2 8e+QfSdTp/+ta4lvi+FL2EO+RIrEQylmjGU13Zx3vBdiiKs0Qti5ly/0ys0xGkbhcp4z6rQ vVnYELEcgta3gYnPKopPQ== X-UI-Out-Filterresults: notjunk:1;V01:K0:m5Vhjx7FASI=:DMRFjWTobIq7ZDgipS1s0M 208tK9NOPKAbLc2zJ+b9WgR4jjN8QpxkUJa6oSkPtbyGvwLnUU2Fj62M6sPtEpWOjcnOJxju3 tsT2hBGTKo/4DwkG83HpaOl9j88OAgF0JKDZsfzgsZv/Al7WU2d/vkVcYuPwRY5ib6YdX7Kef RbgMsA38z49cffGoZPV8lX6mCms1/8UmyBhOF9VkHLkrO1fPgGb9acKL/eBnLCDxwndiomqvW BjNbxoqZbX8XtnRmc3PwUNG4rf9x23V05g04xSaBg2yl9qcDwEzC6ORRwJyHOfEeKENVqkqs5 FHMRDJXmMgIdQcn3ZO3F+6r6FgMkFMovViwoxaGBu3FEwt+PK6zlOd1Tqyyn9lNKh3yl93Kc0 I//5dFTCZU9W5nGNAKdcgSKyJI0y/ntYm58N1QWS7tD19bIMwq6mFwO0+sBAdX2l+JuhpZKiO 1Ofe0Esiebo3lVWdpX0glqdeZGf1Z5PfUtEleENnfjP4RjRAU67i5zs9q6+RHQc2oOeuifkuN kspjGKJnA8+CVKk2o13gmv7biESi5RJQP+Od2e72tJRAMwccN6Mf5klaapE+cHXlg4L0jdXxv SAq7DoGqaJpdCv9JOd/4OoiqYm9gO+2OiJjliaEzFlf+/3eh+jLjP896uEmqqwaD4wgZJ94XR T3PiTypOcXuNOSYqc5QjD7IX3e40Rhc0D4t2WomljSQQOpO10+0kLVCRqt5rDjsnQPnKJfleM 9afgJLLCFuCPRbQb X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 212.227.17.24 X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.21 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.org@gnu.org Original-Sender: "help-gnu-emacs" Xref: news.gmane.org gmane.emacs.help:116678 Archived-At: On 07.05.2018 16:26, Drew Adams wrote: >>> For most functions, passing nil for an &optional parameter is the same >>> as omitting it. >>> If MARKER is not specified, the new marker does not point anywhere. >> >> It's about the return value. >> A marker pointing nowhere, might it be considered valid? > > What do you mean by "valid"? Yes, it's a marker. No, it > doesn't have a buffer or position. The same is true of > other Emacs-Lisp objects, such as overlays: they can exist > without having non-nil values for certain of their properties. > >> Expected such returning nil. > > Why? The doc string is pretty clear that it returns a > marker. And it is clear what happens if arg MARKER is > nil: "the new marker does not point anywhere". > Is there a use-case for a marker pointing nowhere? From my point of view refusing to create such a marker makes sense.