From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.devel Subject: Re: seq-some-p and nil Date: Thu, 03 Sep 2015 12:42:46 -0400 Message-ID: References: <1441295429.4215.0@smtp.gmail.com> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: ger.gmane.org 1441298584 27298 80.91.229.3 (3 Sep 2015 16:43:04 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Thu, 3 Sep 2015 16:43:04 +0000 (UTC) Cc: nicolas@petton.fr, emacs-devel@gnu.org To: Simen =?windows-1252?Q?Heggest=F8yl?= Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Thu Sep 03 18:42:57 2015 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1ZXXbE-0006Vw-Jx for ged-emacs-devel@m.gmane.org; Thu, 03 Sep 2015 18:42:56 +0200 Original-Received: from localhost ([::1]:50269 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZXXbE-0004Ey-Gs for ged-emacs-devel@m.gmane.org; Thu, 03 Sep 2015 12:42:56 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:59749) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZXXbA-0004E9-Tu for emacs-devel@gnu.org; Thu, 03 Sep 2015 12:42:53 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZXXb6-0005Sl-Sg for emacs-devel@gnu.org; Thu, 03 Sep 2015 12:42:52 -0400 Original-Received: from pruche.dit.umontreal.ca ([132.204.246.22]:52571) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZXXb6-0005SV-Ot for emacs-devel@gnu.org; Thu, 03 Sep 2015 12:42:48 -0400 Original-Received: from ceviche.home (lechon.iro.umontreal.ca [132.204.27.242]) by pruche.dit.umontreal.ca (8.14.1/8.14.1) with ESMTP id t83GgkqF016579; Thu, 3 Sep 2015 12:42:46 -0400 Original-Received: by ceviche.home (Postfix, from userid 20848) id 2D6F966110; Thu, 3 Sep 2015 12:42:46 -0400 (EDT) In-Reply-To: <1441295429.4215.0@smtp.gmail.com> ("Simen =?windows-1252?Q?H?= =?windows-1252?Q?eggest=F8yl=22's?= message of "Thu, 03 Sep 2015 17:50:29 +0200") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.0.50 (gnu/linux) X-NAI-Spam-Flag: NO X-NAI-Spam-Threshold: 5 X-NAI-Spam-Score: 0 X-NAI-Spam-Rules: 1 Rules triggered RV5418=0 X-NAI-Spam-Version: 2.3.0.9393 : core <5418> : inlines <3752> : streams <1499243> : uri <2031736> X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 132.204.246.22 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.14 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-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:189522 Archived-At: > Two solutions come to my mind: 1) Make `seq-some-p' a pure t/nil > predicate, or 2) Make it behave like `some' in Common Lisp, which is > to return the first non-nil value which is returned by an invocation > of the predicate. So in CL: I think that functions named "-p" should return values which are fundamentally booleans, but whose non-nil value is unspecified (they can return any non-nil value they fancy and the callers should make assumptions about that non-nil return value). Other than that, the CL behavior looks sane to me. Stefan