From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: "Drew Adams" Newsgroups: gmane.emacs.help Subject: RE: canonical name ending "-p" Date: Fri, 18 Mar 2011 11:31:44 -0700 Message-ID: <4C9FBB09BB6746F1B6B849FF8FBBEC49@us.oracle.com> References: <4D8398DF.6030709@mousecar.com> <877hbw9tp4.fsf@sec.modprobe.de> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Trace: dough.gmane.org 1300473163 23500 80.91.229.12 (18 Mar 2011 18:32:43 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Fri, 18 Mar 2011 18:32:43 +0000 (UTC) To: "'Tom Rauchenwald'" , Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Fri Mar 18 19:32:39 2011 Return-path: Envelope-to: geh-help-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1Q0eTW-0000y0-D8 for geh-help-gnu-emacs@m.gmane.org; Fri, 18 Mar 2011 19:32:39 +0100 Original-Received: from localhost ([127.0.0.1]:43972 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Q0eTN-0002IT-P1 for geh-help-gnu-emacs@m.gmane.org; Fri, 18 Mar 2011 14:32:29 -0400 Original-Received: from [140.186.70.92] (port=33262 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Q0eSk-0002GK-NQ for help-gnu-emacs@gnu.org; Fri, 18 Mar 2011 14:31:52 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Q0eSi-0004te-IX for help-gnu-emacs@gnu.org; Fri, 18 Mar 2011 14:31:49 -0400 Original-Received: from rcsinet10.oracle.com ([148.87.113.121]:20887) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Q0eSi-0004tX-B7 for help-gnu-emacs@gnu.org; Fri, 18 Mar 2011 14:31:48 -0400 Original-Received: from acsinet15.oracle.com (acsinet15.oracle.com [141.146.126.227]) by rcsinet10.oracle.com (Switch-3.4.2/Switch-3.4.2) with ESMTP id p2IIVjsB028808 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Fri, 18 Mar 2011 18:31:46 GMT Original-Received: from acsmt357.oracle.com (acsmt357.oracle.com [141.146.40.157]) by acsinet15.oracle.com (Switch-3.4.2/Switch-3.4.1) with ESMTP id p2IIViV1018567 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Fri, 18 Mar 2011 18:31:44 GMT Original-Received: from abhmt005.oracle.com (abhmt005.oracle.com [141.146.116.14]) by acsmt357.oracle.com (8.12.11.20060308/8.12.11) with ESMTP id p2IIViJP021809; Fri, 18 Mar 2011 13:31:44 -0500 Original-Received: from dradamslap1 (/10.159.39.7) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Fri, 18 Mar 2011 11:31:43 -0700 X-Mailer: Microsoft Office Outlook 11 In-Reply-To: <877hbw9tp4.fsf@sec.modprobe.de> Thread-Index: AcvlmUYobNh7RzASRHufu1NfbjKyrwAAKAkw X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5994 X-Source-IP: acsmt357.oracle.com [141.146.40.157] X-Auth-Type: Internal IP X-CT-RefId: str=0001.0A090207.4D83A511.000B,ss=1,fgs=0 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6 (newer, 3) X-Received-From: 148.87.113.121 X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Users list for the GNU Emacs text editor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.help:80237 Archived-At: > It means predicate. Functions ending in -p return either t > or nil, and variables ending in -p contain either t or nil. Actually, either non-nil (true) or nil (false). "Boolean" in Lisp can mean this or it can mean strictly `t' or `nil'. Generally, any non-nil value is taken to mean true, but for `defcustom' the :type `boolean' limits the value to t or nil. Also, most people do _not_ use `-p' when naming a boolean variable. I use it that way quite often, but some Emacs developers frown on this use. For user options, some people (including me) use the suffix `-flag' for a boolean option. I tend to use `-p' for internal variables (non-options).