From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: ludo@gnu.org (Ludovic =?iso-8859-1?Q?Court=E8s?=) Newsgroups: gmane.lisp.guile.devel Subject: Re: things are eq? but not generated at the same time Date: Wed, 05 Sep 2012 23:58:07 +0200 Message-ID: <87bohkt9n4.fsf@gnu.org> References: NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Trace: ger.gmane.org 1346883322 9400 80.91.229.3 (5 Sep 2012 22:15:22 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 5 Sep 2012 22:15:22 +0000 (UTC) To: guile-devel@gnu.org Original-X-From: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Thu Sep 06 00:15:25 2012 Return-path: Envelope-to: guile-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1T9NsY-0001nw-1n for guile-devel@m.gmane.org; Thu, 06 Sep 2012 00:15:22 +0200 Original-Received: from localhost ([::1]:35591 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1T9NsU-0006Tf-TC for guile-devel@m.gmane.org; Wed, 05 Sep 2012 18:15:18 -0400 Original-Received: from eggs.gnu.org ([208.118.235.92]:34610) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1T9NsP-0006NL-Bg for guile-devel@gnu.org; Wed, 05 Sep 2012 18:15:14 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1T9NsM-0001mN-OO for guile-devel@gnu.org; Wed, 05 Sep 2012 18:15:13 -0400 Original-Received: from plane.gmane.org ([80.91.229.3]:57845) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1T9NsM-0001kH-HU for guile-devel@gnu.org; Wed, 05 Sep 2012 18:15:10 -0400 Original-Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1T9Nia-00088n-65 for guile-devel@gnu.org; Thu, 06 Sep 2012 00:05:04 +0200 Original-Received: from reverse-83.fdn.fr ([80.67.176.83]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 06 Sep 2012 00:05:04 +0200 Original-Received: from ludo by reverse-83.fdn.fr with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 06 Sep 2012 00:05:04 +0200 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 29 Original-X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: reverse-83.fdn.fr X-URL: http://www.fdn.fr/~lcourtes/ X-Revolutionary-Date: 20 Fructidor an 220 de la =?iso-8859-1?Q?R=E9volutio?= =?iso-8859-1?Q?n?= X-PGP-Key-ID: 0xEA52ECF4 X-PGP-Key: http://www.fdn.fr/~lcourtes/ludovic.asc X-PGP-Fingerprint: 83C4 F8E5 10A3 3B4C 5BEA D15D 77DD 95E2 EA52 ECF4 X-OS: x86_64-unknown-linux-gnu User-Agent: Gnus/5.130005 (Ma Gnus v0.5) Emacs/24.2 (gnu/linux) Cancel-Lock: sha1:KlSUzLPp4Py/q/ehGgSH1Aap9hc= X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 80.91.229.3 X-BeenThere: guile-devel@gnu.org X-Mailman-Version: 2.1.14 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 Original-Sender: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.lisp.guile.devel:14864 Archived-At: Hi, Stefan Israelsson Tampe skribis: > If I put, > > (define a #(1)) > (define b #(1)) > > , load the file. Then > >> (eq? a b) > #t The R5RS reads (info "(r5rs) Equivalence predicates"): Since it is an error to modify constant objects (those returned by literal expressions), implementations are permitted, though not required, to share structure between constants where appropriate. And then, these examples: (eq? '(a) '(a)) ==> _unspecified_ (eq? "a" "a") ==> _unspecified_ (eq? "" "") ==> _unspecified_ So no problem here, AFAICS. Ludo’.