From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Andreas Politz Newsgroups: gmane.emacs.help Subject: Re: SPECPDL_INDEX Date: Tue, 06 Jan 2009 16:03:58 +0100 Organization: FH-Trier Message-ID: <1231254304.21719@arno.fh-trier.de> References: NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1231256592 8570 80.91.229.12 (6 Jan 2009 15:43:12 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Tue, 6 Jan 2009 15:43:12 +0000 (UTC) To: help-gnu-emacs@gnu.org Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Tue Jan 06 16:44:24 2009 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 4.50) id 1LKE6N-0007rS-Kp for geh-help-gnu-emacs@m.gmane.org; Tue, 06 Jan 2009 16:44:19 +0100 Original-Received: from localhost ([127.0.0.1]:49550 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1LKE58-0000Cg-2A for geh-help-gnu-emacs@m.gmane.org; Tue, 06 Jan 2009 10:43:02 -0500 Original-Path: news.stanford.edu!headwall.stanford.edu!news.glorb.com!newsfeed00.sul.t-online.de!t-online.de!inka.de!peernews!news.belwue.de!news.uni-kl.de!not-for-mail Original-Newsgroups: gnu.emacs.help Original-Lines: 37 Original-NNTP-Posting-Host: 143-93-54-11.arno.fh-trier.de Original-X-Trace: news.uni-kl.de 1231254361 26731 143.93.54.11 (6 Jan 2009 15:06:01 GMT) Original-X-Complaints-To: usenet@news.uni-kl.de Original-NNTP-Posting-Date: Tue, 6 Jan 2009 15:06:01 +0000 (UTC) User-Agent: Mozilla-Thunderbird 2.0.0.17 (X11/20081018) In-Reply-To: Cache-Post-Path: arno.fh-trier.de!unknown@dslb-084-059-217-015.pools.arcor-ip.net X-Cache: nntpcache 3.0.1 (see http://www.nntpcache.org/) Original-Xref: news.stanford.edu gnu.emacs.help:165779 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:61116 Archived-At: A. Soare wrote: > Can someone illuminate me what is the purpose of the `count' variable in the function `redisplay', please? > > > Thanks in advance. DEFUN ("redisplay", Fredisplay, Sredisplay, 0, 1, 0, doc: /* Perform redisplay if no input is available. If optional arg FORCE is non-nil or `redisplay-dont-pause' is non-nil, perform a full redisplay even if input is available. Return t if redisplay was performed, nil otherwise. */) (force) Lisp_Object force; { int count; swallow_events (1); if ((detect_input_pending_run_timers (1) && NILP (force) && !redisplay_dont_pause) || !NILP (Vexecuting_kbd_macro)) return Qnil; count = SPECPDL_INDEX (); if (!NILP (force) && !redisplay_dont_pause) specbind (Qredisplay_dont_pause, Qt); redisplay_preserve_echo_area (2); unbind_to (count, Qnil); return Qt; } I think it's an index into the variable binding stack to which the c-function unwind_to later restores state. Maybe take a look at the definition of the let form in eval.c . -ap