From mboxrd@z Thu Jan 1 00:00:00 1970 Path: main.gmane.org!not-for-mail From: Andy Wingo Newsgroups: gmane.lisp.guile.devel Subject: Re: typechecking Date: Sun, 30 May 2004 15:00:21 +0100 Sender: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Message-ID: <1085925620.23380.77.camel@localhost> References: <16486.52591.672130.224861@localhost.localdomain> <87brkwc6f7.fsf@zagadka.ping.de> <16544.2271.454230.492574@localhost.localdomain> <40A5DFF2.80004@dirk-herrmanns-seiten.de> <16564.54949.13882.819772@localhost.localdomain> NNTP-Posting-Host: deer.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 7bit X-Trace: sea.gmane.org 1085930376 27511 80.91.224.253 (30 May 2004 15:19:36 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Sun, 30 May 2004 15:19:36 +0000 (UTC) Original-X-From: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Sun May 30 17:19:27 2004 Return-path: Original-Received: from lists.gnu.org ([199.232.76.165]) by deer.gmane.org with esmtp (Exim 3.35 #1 (Debian)) id 1BUS5v-00071M-00 for ; Sun, 30 May 2004 17:19:27 +0200 Original-Received: from localhost ([127.0.0.1] helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.33) id 1BUS63-00008w-P1 for guile-devel@m.gmane.org; Sun, 30 May 2004 11:19:35 -0400 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.33) id 1BUS5z-00007s-7x for guile-devel@gnu.org; Sun, 30 May 2004 11:19:31 -0400 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.33) id 1BUS5x-00007T-Ef for guile-devel@gnu.org; Sun, 30 May 2004 11:19:30 -0400 Original-Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.33) id 1BUS5x-00007J-6x for guile-devel@gnu.org; Sun, 30 May 2004 11:19:29 -0400 Original-Received: from [216.166.232.203] (helo=johnson-resources.com) by monty-python.gnu.org with esmtp (TLSv1:DES-CBC3-SHA:168) (Exim 4.34) id 1BUS4v-00062T-SW for guile-devel@gnu.org; Sun, 30 May 2004 11:18:26 -0400 Original-Received: from localhost (mantis.schoolnet.na [::ffff:196.44.140.238]) (AUTH: LOGIN wingo) by johnson-resources.com with esmtp; Sun, 30 May 2004 11:13:20 -0400 Original-Received: from wingo by localhost with local (Exim 3.36 #1 (Debian)) id 1BUQrX-0002Dg-00 for ; Sun, 30 May 2004 15:00:31 +0100 Original-To: guile-devel@gnu.org In-Reply-To: <16564.54949.13882.819772@localhost.localdomain> X-Mailer: Ximian Evolution 1.5.7 X-BeenThere: guile-devel@gnu.org X-Mailman-Version: 2.1.4 Precedence: list List-Id: "Developers list for Guile, the GNU extensibility library" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Xref: main.gmane.org gmane.lisp.guile.devel:3776 X-Report-Spam: http://spam.gmane.org/gmane.lisp.guile.devel:3776 On Wed, 2004-05-26 at 19:40 +0200, Han-Wen Nienhuys wrote: > It would be interesting to see if we could map the Scheme semantics > (true = !SCM_BOOL_F) to C. That would require mapping SCM_BOOL_F to > (void*)0x0. Is this desirable, and does anyone see a possibility for this? I've been caught by this error a few times, and the scheme true/false semantics do map nicely to C. Howeverm the idea has some problems. For one, I don't think passing a union to `if' (which is what SCM is in SCM_DEBUG_TYPING_STRICTNESS==2) works. Secondly, I might be bit-stupid, but after about five minutes of looking, I can't find a nice set of tc3 type tags having #f==0 for which a fast SCM_IMP can be defined. This hints that trying to do #f==0 is a bad idea because it constrains the implementation. Dunno, just my cent-and-a-half. -- Andy Wingo _______________________________________________ Guile-devel mailing list Guile-devel@gnu.org http://lists.gnu.org/mailman/listinfo/guile-devel