From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: "alin.s" Newsgroups: gmane.emacs.devel Subject: special form and macro Date: Sat, 20 Feb 2010 05:16:42 -0800 (PST) Message-ID: <27666297.post@talk.nabble.com> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1266671823 9513 80.91.229.12 (20 Feb 2010 13:17:03 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sat, 20 Feb 2010 13:17:03 +0000 (UTC) To: Emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sat Feb 20 14:16:55 2010 Return-path: Envelope-to: ged-emacs-devel@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 1NipCY-0000au-Nh for ged-emacs-devel@m.gmane.org; Sat, 20 Feb 2010 14:16:55 +0100 Original-Received: from localhost ([127.0.0.1]:42025 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NipCV-0002Hr-Ly for ged-emacs-devel@m.gmane.org; Sat, 20 Feb 2010 08:16:51 -0500 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1NipCQ-0002Hm-Mw for emacs-devel@gnu.org; Sat, 20 Feb 2010 08:16:46 -0500 Original-Received: from [140.186.70.92] (port=37197 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NipCO-0002He-SO for Emacs-devel@gnu.org; Sat, 20 Feb 2010 08:16:46 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69) (envelope-from ) id 1NipCN-00053Q-Qt for Emacs-devel@gnu.org; Sat, 20 Feb 2010 08:16:44 -0500 Original-Received: from kuber.nabble.com ([216.139.236.158]:38961) by eggs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1NipCN-00053J-N3 for Emacs-devel@gnu.org; Sat, 20 Feb 2010 08:16:43 -0500 Original-Received: from isper.nabble.com ([192.168.236.156]) by kuber.nabble.com with esmtp (Exim 4.63) (envelope-from ) id 1NipCM-000634-Uh for Emacs-devel@gnu.org; Sat, 20 Feb 2010 05:16:42 -0800 X-Nabble-From: alinsoar@voila.fr X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6 (newer, 3) X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:121247 Archived-At: What difference exists between a macro and a user-defined special form? In emacs the user cannot define special forms, maybe because the macros keep the place of special forms? A special form should be defined as (special (var1 ... varn) (lambda () ... )) During application, var1 ... varn should be initialized temporary inside the environment with the unevaluated values of the call. (name val1 ... valn). But this is exactly the definition of a macro. Is there a difference . Is there a computation that one can do and the other not? -- View this message in context: http://old.nabble.com/special-form-and-macro-tp27666297p27666297.html Sent from the Emacs - Dev mailing list archive at Nabble.com.