From mboxrd@z Thu Jan 1 00:00:00 1970 Path: main.gmane.org!not-for-mail From: prj@po.cwru.edu (Paul Jarc) Newsgroups: gmane.lisp.guile.devel Subject: Re: GH replacement proposal (includes a bit of Unicode) Date: Wed, 21 Apr 2004 17:46:32 -0400 Organization: What did you have in mind? A short, blunt, human pyramid? Sender: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Message-ID: References: <4086A1BF.9C8F7914@veritas.com> <87vfjtm2v5.fsf@zagadka.ping.de> NNTP-Posting-Host: deer.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: sea.gmane.org 1082584945 22390 80.91.224.253 (21 Apr 2004 22:02:25 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Wed, 21 Apr 2004 22:02:25 +0000 (UTC) Cc: bkorb@veritas.com, guile-devel@gnu.org Original-X-From: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Thu Apr 22 00:02:10 2004 Return-path: Original-Received: from monty-python.gnu.org ([199.232.76.173]) by deer.gmane.org with esmtp (Exim 3.35 #1 (Debian)) id 1BGPnG-0006lX-00 for ; Thu, 22 Apr 2004 00:02:10 +0200 Original-Received: from localhost ([127.0.0.1] helo=monty-python.gnu.org) by monty-python.gnu.org with esmtp (Exim 4.30) id 1BGPkk-000216-6t for guile-devel@m.gmane.org; Wed, 21 Apr 2004 17:59:34 -0400 Original-Received: from list by monty-python.gnu.org with tmda-scanned (Exim 4.30) id 1BGPcw-00080o-Us for guile-devel@gnu.org; Wed, 21 Apr 2004 17:51:30 -0400 Original-Received: from mail by monty-python.gnu.org with spam-scanned (Exim 4.30) id 1BGPbV-0006Sx-Ev for guile-devel@gnu.org; Wed, 21 Apr 2004 17:50:33 -0400 Original-Received: from [129.22.104.47] (helo=mirapoint2.tis.cwru.edu) by monty-python.gnu.org with esmtp (TLSv1:DES-CBC3-SHA:168) (Exim 4.30) id 1BGPYE-0004rZ-Ga for guile-devel@gnu.org; Wed, 21 Apr 2004 17:46:38 -0400 Original-Received: from multivac.cwru.edu (multivac.ITS.CWRU.Edu [129.22.114.26]) by mirapoint2.tis.cwru.edu (MOS 3.4.3-CR) with SMTP id AXS88531; Wed, 21 Apr 2004 17:46:33 -0400 (EDT) Original-Received: (qmail 27533 invoked by uid 500); 21 Apr 2004 21:46:55 -0000 Original-To: Marius Vollmer In-Reply-To: <87vfjtm2v5.fsf@zagadka.ping.de> (Marius Vollmer's message of "Wed, 21 Apr 2004 23:34:54 +0200") Mail-Copies-To: nobody Mail-Followup-To: Marius Vollmer , bkorb@veritas.com, guile-devel@gnu.org Original-Lines: 23 User-Agent: Gnus/5.110002 (No Gnus v0.2) Emacs/21.3 (gnu/linux) 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:3617 X-Report-Spam: http://spam.gmane.org/gmane.lisp.guile.devel:3617 Marius Vollmer wrote: > Is there an advantage of having instead > > scm_to_bool --- return 0 for #f, 1 for #t, else signal error It would be more symmetric, as I suggested earlier. A procedure argument might have defined meanings for #f and #t, and later it might be extended with defined meanings for other values. Now suppose a new caller passes 42, expecting the new extended semantics, but it happens to be calling an old version of the procedure which only supports boolean values. Having a scm_to_bool which signals an error here would help detect this problem early. > What about > > scm_from_bool --- return #f for 0, #t for 1, else signal error I think 1 in C is sufficiently less distinctive than #t in Scheme that this would not be good. paul _______________________________________________ Guile-devel mailing list Guile-devel@gnu.org http://mail.gnu.org/mailman/listinfo/guile-devel