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,gmane.lisp.guile.user Subject: Re: overriding car/cdr Date: Sun, 08 Feb 2004 15:56:09 -0500 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: <1074246064.6729.23.camel@localhost> <87vfn9ufvw.fsf@zagadka.ping.de> <400FF648.3080706@dirk-herrmanns-seiten.de> <200401221842.KAA20956@morrowfield.regexps.com> <40110961.1040808@dirk-herrmanns-seiten.de> <200401231716.JAA26107@morrowfield.regexps.com> <87oesus7kg.fsf@zagadka.ping.de> <20040124120954.GB6589@www> <87k73hpj9n.fsf@zagadka.ping.de> <87znbtbfzt.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 1076273887 4061 80.91.224.253 (8 Feb 2004 20:58:07 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Sun, 8 Feb 2004 20:58:07 +0000 (UTC) Cc: guile-user@gnu.org, rm@fabula.de, guile-devel@gnu.org Original-X-From: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Sun Feb 08 21:57:58 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 1Apw05-0001r0-00 for ; Sun, 08 Feb 2004 21:57:57 +0100 Original-Received: from localhost ([127.0.0.1] helo=monty-python.gnu.org) by monty-python.gnu.org with esmtp (Exim 4.24) id 1ApvzT-0003qA-Tz for guile-devel@m.gmane.org; Sun, 08 Feb 2004 15:57:19 -0500 Original-Received: from list by monty-python.gnu.org with tmda-scanned (Exim 4.24) id 1ApvzL-0003oB-8N for guile-devel@gnu.org; Sun, 08 Feb 2004 15:57:11 -0500 Original-Received: from mail by monty-python.gnu.org with spam-scanned (Exim 4.24) id 1Apvyp-0003gJ-ES for guile-devel@gnu.org; Sun, 08 Feb 2004 15:57:10 -0500 Original-Received: from [129.22.104.47] (helo=mirapoint2.tis.cwru.edu) by monty-python.gnu.org with esmtp (Exim 4.24) id 1Apvyp-0003Kk-44 for guile-devel@gnu.org; Sun, 08 Feb 2004 15:56:39 -0500 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 AJK57655; Sun, 8 Feb 2004 15:56:10 -0500 (EST) Original-Received: (qmail 19957 invoked by uid 500); 8 Feb 2004 20:56:31 -0000 Original-To: Marius Vollmer In-Reply-To: <87znbtbfzt.fsf@zagadka.ping.de> (Marius Vollmer's message of "Sun, 08 Feb 2004 19:09:10 +0100") Mail-Copies-To: nobody Mail-Followup-To: Marius Vollmer , rm@fabula.de, guile-user@gnu.org, guile-devel@gnu.org Original-Lines: 29 User-Agent: Gnus/5.110002 (No Gnus v0.2) Emacs/21.3 (gnu/linux) X-BeenThere: guile-devel@gnu.org X-Mailman-Version: 2.1.2 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:3351 gmane.lisp.guile.user:2770 X-Report-Spam: http://spam.gmane.org/gmane.lisp.guile.devel:3351 Marius Vollmer wrote: > But car/cdr are not a good way to work with general sequences. Think > of vectors. car/cdr certainly can be made to work with vectors. Making them work with arbitrary user-defined structures would give us a lot of flexibility without too much work. If there is a significant amount of C code using SCM_CAR/SCM_CDR with non-pair objects, then it might be best to leave them unchanged. But I think the Scheme-level cxr functions would be a good place to make the change. > We should not try hard to turn car/cdr into something abstract > (which they are not, even their names come from the lowest level). Of course they currently are not, but that doesn't (nor do the names) tell us whether it would be good if they were more abstract. > Somehthing like the 'sequence' concept of Common Lisp is a better > approach, I'd say. AFAICT, that would involve a whole new set of procedures to work with this new data type. I'm suggesting modifying the existing procedures so that most existing code would automatically be able to take advantage of the new flexibility, with no further changes needed. paul _______________________________________________ Guile-devel mailing list Guile-devel@gnu.org http://mail.gnu.org/mailman/listinfo/guile-devel