From mboxrd@z Thu Jan 1 00:00:00 1970 Path: main.gmane.org!not-for-mail From: Tom Lord Newsgroups: gmane.lisp.guile.user,gmane.lisp.guile.devel Subject: Re: Worrying development Date: Fri, 23 Jan 2004 09:16:25 -0800 (PST) Sender: guile-user-bounces+guile-user=m.gmane.org@gnu.org Message-ID: <200401231716.JAA26107@morrowfield.regexps.com> 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> NNTP-Posting-Host: deer.gmane.org X-Trace: sea.gmane.org 1074877519 6205 80.91.224.253 (23 Jan 2004 17:05:19 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Fri, 23 Jan 2004 17:05:19 +0000 (UTC) Cc: guile-user@gnu.org, guile-devel@gnu.org, mvo@zagadka.de Original-X-From: guile-user-bounces+guile-user=m.gmane.org@gnu.org Fri Jan 23 18:05:10 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 1Ak4k2-0002BQ-00 for ; Fri, 23 Jan 2004 18:05:10 +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 1Ak4jO-0006jy-8w for guile-user@m.gmane.org; Fri, 23 Jan 2004 12:04:30 -0500 Original-Received: from list by monty-python.gnu.org with tmda-scanned (Exim 4.24) id 1Ak4ib-0006hx-3m for guile-user@gnu.org; Fri, 23 Jan 2004 12:03:41 -0500 Original-Received: from mail by monty-python.gnu.org with spam-scanned (Exim 4.24) id 1Ak4i4-0006Gh-A5 for guile-user@gnu.org; Fri, 23 Jan 2004 12:03:40 -0500 Original-Received: from [65.234.195.150] (helo=morrowfield.regexps.com) by monty-python.gnu.org with esmtp (Exim 4.24) id 1Ak4i3-0006Fm-6V; Fri, 23 Jan 2004 12:03:07 -0500 Original-Received: (from lord@localhost) by morrowfield.regexps.com (8.9.1/8.9.1) id JAA26107; Fri, 23 Jan 2004 09:16:25 -0800 (PST) (envelope-from lord@morrowfield.regexps.com) Original-To: dirk@dirk-herrmanns-seiten.de In-reply-to: <40110961.1040808@dirk-herrmanns-seiten.de> (message from Dirk Herrmann on Fri, 23 Jan 2004 12:45:37 +0100) X-BeenThere: guile-user@gnu.org X-Mailman-Version: 2.1.2 Precedence: list List-Id: General Guile related discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guile-user-bounces+guile-user=m.gmane.org@gnu.org Xref: main.gmane.org gmane.lisp.guile.user:2699 gmane.lisp.guile.devel:3293 X-Report-Spam: http://spam.gmane.org/gmane.lisp.guile.user:2699 > From: Dirk Herrmann > First: It's not a matter of whether users *need* to make certain > assumptions: It's a matter of interface definition. Scheme defines the > string data type and together with it, it defines the semantics of > operations on it. Please show me what existing lines of the Scheme standard will have to change if mutation-sharing shared substrings are added. The standard (not very formally but clearly enough) says that the standard procedures which construct strings allocate fresh locations for the contents of those strings. That means that none of those procedures create mutation-sharing shared substrings -- nobody has proposed anything different. I think you are imagining that there is an additional requirement in the standard: that any procedure at all which creates a new string must allocate fresh locations for its contents. But that additional requirement isn't there. Scheme programmers can not assume that that requirement is part of Scheme. Mutation-sharing shared substrings are an upwards compatible extension to the Scheme standard. They break no correct programs. They enable new kinds of programs. -t _______________________________________________ Guile-user mailing list Guile-user@gnu.org http://mail.gnu.org/mailman/listinfo/guile-user