From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Andreas =?UTF-8?Q?R=C3=B6hler?= Newsgroups: gmane.emacs.bugs Subject: bug#15117: 24.3.50; doc of `(forward|backward)-*': state return value Date: Tue, 11 Feb 2014 13:10:23 +0100 Message-ID: <52FA132F.2030906@easy-emacs.de> References: <1dc76f7a-5481-41df-b976-ec22229d7283@default> <874n4a42f0.fsf@building.gnus.org> <1281d0fd-77cb-45e2-b99d-f4ad24b0fc4e@default> <2fefcbaf-9417-4f57-93af-490ea73aea98@default> <52FA00E7.2050108@easy-emacs.de> <87vbwl99wp.fsf@yahoo.fr> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Trace: ger.gmane.org 1392120431 9739 80.91.229.3 (11 Feb 2014 12:07:11 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Tue, 11 Feb 2014 12:07:11 +0000 (UTC) Cc: 15117@debbugs.gnu.org To: Nicolas Richard Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Tue Feb 11 13:07:19 2014 Return-path: Envelope-to: geb-bug-gnu-emacs@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 1WDC7Q-0003d6-F4 for geb-bug-gnu-emacs@m.gmane.org; Tue, 11 Feb 2014 13:07:16 +0100 Original-Received: from localhost ([::1]:32993 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WDC7P-0003pO-RK for geb-bug-gnu-emacs@m.gmane.org; Tue, 11 Feb 2014 07:07:15 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:55927) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WDC7I-0003p0-3l for bug-gnu-emacs@gnu.org; Tue, 11 Feb 2014 07:07:13 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WDC7C-0004eP-MJ for bug-gnu-emacs@gnu.org; Tue, 11 Feb 2014 07:07:08 -0500 Original-Received: from debbugs.gnu.org ([140.186.70.43]:44789) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WDC7C-0004eL-Ih for bug-gnu-emacs@gnu.org; Tue, 11 Feb 2014 07:07:02 -0500 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.80) (envelope-from ) id 1WDC7C-0002jZ-Bu for bug-gnu-emacs@gnu.org; Tue, 11 Feb 2014 07:07:02 -0500 X-Loop: help-debbugs@gnu.org Resent-From: Andreas =?UTF-8?Q?R=C3=B6hler?= Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Tue, 11 Feb 2014 12:07:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 15117 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: wontfix Original-Received: via spool by 15117-submit@debbugs.gnu.org id=B15117.139212038610455 (code B ref 15117); Tue, 11 Feb 2014 12:07:02 +0000 Original-Received: (at 15117) by debbugs.gnu.org; 11 Feb 2014 12:06:26 +0000 Original-Received: from localhost ([127.0.0.1]:45971 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WDC6c-0002iY-1h for submit@debbugs.gnu.org; Tue, 11 Feb 2014 07:06:26 -0500 Original-Received: from moutng.kundenserver.de ([212.227.17.9]:57961) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WDC6Z-0002iI-L7 for 15117@debbugs.gnu.org; Tue, 11 Feb 2014 07:06:24 -0500 Original-Received: from purzel.sitgens (brln-4d0c6463.pool.mediaWays.net [77.12.100.99]) by mrelayeu.kundenserver.de (node=mreue102) with ESMTP (Nemesis) id 0MeBeI-1Vpblx3zEU-00PrsZ; Tue, 11 Feb 2014 13:06:16 +0100 User-Agent: Mozilla/5.0 (X11; Linux i686; rv:24.0) Gecko/20100101 Thunderbird/24.2.0 In-Reply-To: <87vbwl99wp.fsf@yahoo.fr> X-Provags-ID: V02:K0:+ZjjFn/v4nWcPMreODbEiU6N7CDntqcvHSOTfY6mXDv chVn14eEGhwyBNAv5ZHT/oumbjOq4mkl5XUoTd/+eFwBJBgTG8 wUO7wirJwb6os+jDaviIJtWgTv2qcB7EdeFtkjpyBIoyNfD/ca YnFl0gNgOhEuB7mGKqgb1dCIdlEAngcfUYRnGxtj8B7CCz9jOY sKmyXMIvpg+NwJpP+s3URIg2sJmpGDUhj8Dx3M4mxCRzY9l5Pg ISlakpjOigxMz7/dmF5X+CtpdIp70CpQcC+z/7rgwC3lux1sCs uOIChb6ewLgiiXLVpl3vIjh0fD6TTd6aJIVH3Y2AcHj2RrNapt eomYa/gKItpJYXw+lBT+eIrRXnjEXeHBIjfXziK// X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.15 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 140.186.70.43 X-BeenThere: bug-gnu-emacs@gnu.org List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Original-Sender: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.bugs:85373 Archived-At: Am 11.02.2014 12:16, schrieb Nicolas Richard: > Andreas Röhler writes: >> Am 11.02.2014 05:01, schrieb Stefan Monnier: >>> Says you. For me (and most definitions of side-effects I've ever seen), >>> a side-effecting function is something like a function where the calls >>> can't simply be replaced by their return value. > >> Can't see a logic link between a possible return value and the notion of side-effect. >> It all depends from the purpose of the function. > > I guess this is a slight misunderstanding. The notion of side-effect is > well defined in CS: « a function or expression is said to have a side > effect if, in addition to returning a value, it also modifies some state > or has an observable interaction with calling functions or the outside > world. » > (http://en.wikipedia.org/wiki/Side_effect_%28computer_science%29) > WP is often good, sometimes bad, sometimes just an agent of CIA, NSA and their satellites. Saying in WP is no proof at all. If you read "in addition to returning a value": functions must not return a value, but might have side-effects > The notions of "mostly-unintended effect" (like so: (defun > my-point-at-eol (progn (end-of-line) (point)))) or "multi-purpose > functions by means of global variables" (e.g. the use of 'org-ts-what in > org-at-timestamp-p -- which is kind of scary if I may say) are only > special cases of side effects. > It's also not about unintended side-effect, also also about intended.