From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED.blaine.gmane.org!not-for-mail From: Mark H Weaver Newsgroups: gmane.lisp.guile.devel Subject: Re: guile 3 update, halloween edition Date: Sat, 02 Nov 2019 15:33:55 -0400 Message-ID: <87pniaoywx.fsf@netris.org> References: <87o8xyhtz6.fsf@pobox.com> <877e4irh0g.fsf@netris.org> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: blaine.gmane.org; posting-host="blaine.gmane.org:195.159.176.226"; logging-data="269346"; mail-complaints-to="usenet@blaine.gmane.org" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.3 (gnu/linux) Cc: guile-devel@gnu.org To: Andy Wingo Original-X-From: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Sat Nov 02 20:35:18 2019 Return-path: Envelope-to: guile-devel@m.gmane.org Original-Received: from lists.gnu.org ([209.51.188.17]) by blaine.gmane.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1iQzB7-0017tF-JC for guile-devel@m.gmane.org; Sat, 02 Nov 2019 20:35:17 +0100 Original-Received: from localhost ([::1]:50230 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iQzB5-0006fr-R4 for guile-devel@m.gmane.org; Sat, 02 Nov 2019 15:35:15 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:33938) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iQzB0-0006fi-Iw for guile-devel@gnu.org; Sat, 02 Nov 2019 15:35:11 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iQzAz-0002lp-GH for guile-devel@gnu.org; Sat, 02 Nov 2019 15:35:10 -0400 Original-Received: from world.peace.net ([64.112.178.59]:59792) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iQzAz-0002lK-D0 for guile-devel@gnu.org; Sat, 02 Nov 2019 15:35:09 -0400 Original-Received: from mhw by world.peace.net with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1iQzAx-0006yx-Ah; Sat, 02 Nov 2019 15:35:07 -0400 In-Reply-To: <877e4irh0g.fsf@netris.org> (Mark H. Weaver's message of "Sat, 02 Nov 2019 01:20:04 -0400") X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 64.112.178.59 X-BeenThere: guile-devel@gnu.org X-Mailman-Version: 2.1.23 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" Xref: news.gmane.org gmane.lisp.guile.devel:20140 Archived-At: Mark H Weaver writes: > Andy Wingo writes: > >> [...] There will be bijections >> between a Guile's "throw" arguments and structured exceptions, mostly >> inspired with what Julian did in the R6RS layer already. > > For the record, the bijection between R6RS conditions and Guile's throw > arguments was my work, not Julian's. See: > > https://git.savannah.gnu.org/cgit/guile.git/commit/?id=02500d44775a77e46febfd47a0dab8233b0c99d0 I should clarify that it's not a bijection in the strict mathematical sense of the word, and it's not obvious to me how to define an efficient bijection here. I assumed that you were using the term loosely to describe an approximate bijection in non-pathological cases, but perhaps I misunderstood. If you think you have a true bijection that can be efficiently implemented, I'd like to hear the details. Anyway, prior to the commit above, there was only a mapping in one direction, so nothing even remotely close to a bijection. Thanks, Mark