From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Mark H Weaver Newsgroups: gmane.lisp.guile.devel Subject: (set! (@@ MOD NAME) EXP) considered harmful Date: Wed, 02 Sep 2009 12:17:11 -0400 Message-ID: <877hwhqq2g.fsf@netris.org> NNTP-Posting-Host: lo.gmane.org X-Trace: ger.gmane.org 1251908843 31205 80.91.229.12 (2 Sep 2009 16:27:23 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 2 Sep 2009 16:27:23 +0000 (UTC) To: guile-devel@gnu.org Original-X-From: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Wed Sep 02 18:27:16 2009 Return-path: Envelope-to: guile-devel@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.50) id 1Misg0-0008Ps-0Y for guile-devel@m.gmane.org; Wed, 02 Sep 2009 18:27:16 +0200 Original-Received: from localhost ([127.0.0.1]:57485 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Misfz-0007U5-Dm for guile-devel@m.gmane.org; Wed, 02 Sep 2009 12:27:15 -0400 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1MisWS-0007K7-VV for guile-devel@gnu.org; Wed, 02 Sep 2009 12:17:25 -0400 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1MisWN-0007Eh-EI for guile-devel@gnu.org; Wed, 02 Sep 2009 12:17:23 -0400 Original-Received: from [199.232.76.173] (port=33047 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1MisWN-0007EL-5Q for guile-devel@gnu.org; Wed, 02 Sep 2009 12:17:19 -0400 Original-Received: from world.peace.net ([204.107.200.8]:40686) by monty-python.gnu.org with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1MisWL-0007xp-8h for guile-devel@gnu.org; Wed, 02 Sep 2009 12:17:19 -0400 Original-Received: from localhost ([127.0.0.1] helo=debxo ident=hope0) by world.peace.net with esmtp (Exim 4.69) (envelope-from ) id 1MisWF-0002kL-Pk; Wed, 02 Sep 2009 12:17:11 -0400 X-detected-operating-system: by monty-python.gnu.org: GNU/Linux 2.6 (newer, 3) X-BeenThere: guile-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Developers list for Guile, the GNU extensibility library" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Errors-To: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.lisp.guile.devel:9252 Archived-At: The ability to set! arbitrary module top-level variables from outside the module, using the syntax (set! (@@ MOD NAME) EXP), destroys our ability to several important optimizations. As long as such ability exists, we must pessimistically assume that any module top-level variable might change at any time, which means, for example, that we cannot inline top-level procedure applications from within the module itself. This could be a HUGE efficiency win in the common case where such top-level procedures are never set! from within the module. Now that we have proper hygienic macros, is this functionality still required? If we're going to remove it, pre-2.0 seems like a good time to do so. We won't get another opportunity for several years. Mark