From mboxrd@z Thu Jan 1 00:00:00 1970 Path: main.gmane.org!not-for-mail From: Bruce Korb Newsgroups: gmane.lisp.guile.devel Subject: Re: illegal uses of define in guile Date: Mon, 14 Oct 2002 10:49:50 -0700 Sender: guile-devel-admin@gnu.org Message-ID: <3DAB03BE.14E930B2@pacbell.net> References: NNTP-Posting-Host: localhost.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Trace: main.gmane.org 1034617850 26092 127.0.0.1 (14 Oct 2002 17:50:50 GMT) X-Complaints-To: usenet@main.gmane.org NNTP-Posting-Date: Mon, 14 Oct 2002 17:50:50 +0000 (UTC) Cc: guile-devel@gnu.org Return-path: Original-Received: from monty-python.gnu.org ([199.232.76.173]) by main.gmane.org with esmtp (Exim 3.35 #1 (Debian)) id 1819Mf-0006mh-00 for ; Mon, 14 Oct 2002 19:50:49 +0200 Original-Received: from localhost ([127.0.0.1] helo=monty-python.gnu.org) by monty-python.gnu.org with esmtp (Exim 4.10) id 1819MP-0006iN-00; Mon, 14 Oct 2002 13:50:33 -0400 Original-Received: from list by monty-python.gnu.org with tmda-scanned (Exim 4.10) id 1819Lq-0006cu-00 for guile-devel@gnu.org; Mon, 14 Oct 2002 13:49:58 -0400 Original-Received: from mail by monty-python.gnu.org with spam-scanned (Exim 4.10) id 1819Lo-0006ce-00 for guile-devel@gnu.org; Mon, 14 Oct 2002 13:49:57 -0400 Original-Received: from bay-bridge.veritas.com ([143.127.3.10] helo=mtvmime02.veritas.com) by monty-python.gnu.org with esmtp (Exim 4.10) id 1819Ln-0006cS-00 for guile-devel@gnu.org; Mon, 14 Oct 2002 13:49:56 -0400 Original-Received: from megami (unverified) by mtvmime02.veritas.com (Content Technologies SMTPRS 4.2.10) with SMTP id ; Mon, 14 Oct 2002 10:50:08 -0700 Original-Received: from pacbell.net(ellen.veritas.com[10.180.88.137]) (1801 bytes) by megami via sendmail with P:esmtp/R:smart_host/T:smtp (sender: ) id for ; Mon, 14 Oct 2002 10:49:53 -0700 (PDT) (Smail-3.2.0.101 1997-Dec-17 #15 built 2001-Aug-30) X-Mailer: Mozilla 4.79 [en] (X11; U; SunOS 5.8 sun4u) X-Accept-Language: en Original-To: Dirk Herrmann Errors-To: guile-devel-admin@gnu.org X-BeenThere: guile-devel@gnu.org X-Mailman-Version: 2.0.11 Precedence: bulk List-Help: List-Post: List-Subscribe: , List-Id: Developers list for Guile, the GNU extensibility library List-Unsubscribe: , List-Archive: Xref: main.gmane.org gmane.lisp.guile.devel:1550 X-Report-Spam: http://spam.gmane.org/gmane.lisp.guile.devel:1550 Dirk Herrmann wrote: > > Currently, guile allows the following: > (if (not (defined? '%load-verbosely)) > (define %load-verbosely #f)) I do that. > This is in contrast to R5RS (maybe even already in contrast to R4RS, > but I haven't checked that). Allowing such placements of define will make > it impossible to determine statically whether after evaluation of the > form the corresponding identifier will be bound or not. That is, we > should disallow this behaviour. Just because static analysis is hard/difficult/impossible does not mean you have to disallow the construct. It may mean you have to disable "memoization" or "optimization" of it -- that's okay. But invalidating peoples work just because you have an optimization problem, ... well it is as bad as saying you cannot alias an "intptr_t" with a pointer in C. > Second, we should decide about how to deal with such forms. Since guile > has allowed this before, there may exist code that makes use of this > feature. It will, however, be difficult to support this feature as > 'deprecated' when separating memoization and execution. :-( _______________________________________________ Guile-devel mailing list Guile-devel@gnu.org http://mail.gnu.org/mailman/listinfo/guile-devel