From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Mark H Weaver Newsgroups: gmane.lisp.guile.bugs Subject: bug#24102: Use guile variable objects as SRFI-111 boxes. Date: Fri, 05 Aug 2016 00:37:40 -0400 Message-ID: <8760rfygob.fsf@netris.org> References: <87a8grygyc.fsf@netris.org> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: blaine.gmane.org 1470371901 819 195.159.176.226 (5 Aug 2016 04:38:21 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Fri, 5 Aug 2016 04:38:21 +0000 (UTC) User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.1 (gnu/linux) Cc: 24102@debbugs.gnu.org To: "Glenn Michaels" Original-X-From: bug-guile-bounces+guile-bugs=m.gmane.org@gnu.org Fri Aug 05 06:38:18 2016 Return-path: Envelope-to: guile-bugs@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1bVWtl-0007pZ-7n for guile-bugs@m.gmane.org; Fri, 05 Aug 2016 06:38:17 +0200 Original-Received: from localhost ([::1]:42751 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bVWth-0004DS-NZ for guile-bugs@m.gmane.org; Fri, 05 Aug 2016 00:38:13 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:55793) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bVWtb-0004B6-Dx for bug-guile@gnu.org; Fri, 05 Aug 2016 00:38:08 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bVWtX-000813-8m for bug-guile@gnu.org; Fri, 05 Aug 2016 00:38:06 -0400 Original-Received: from debbugs.gnu.org ([208.118.235.43]:58736) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bVWtX-00080x-5L for bug-guile@gnu.org; Fri, 05 Aug 2016 00:38:03 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1bVWtW-0002Jg-FX for bug-guile@gnu.org; Fri, 05 Aug 2016 00:38:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Mark H Weaver Original-Sender: "Debbugs-submit" Resent-CC: bug-guile@gnu.org Resent-Date: Fri, 05 Aug 2016 04:38:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 24102 X-GNU-PR-Package: guile X-GNU-PR-Keywords: patch Original-Received: via spool by 24102-submit@debbugs.gnu.org id=B24102.14703718798896 (code B ref 24102); Fri, 05 Aug 2016 04:38:02 +0000 Original-Received: (at 24102) by debbugs.gnu.org; 5 Aug 2016 04:37:59 +0000 Original-Received: from localhost ([127.0.0.1]:56033 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1bVWtT-0002JP-28 for submit@debbugs.gnu.org; Fri, 05 Aug 2016 00:37:59 -0400 Original-Received: from world.peace.net ([50.252.239.5]:42140) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1bVWtR-0002JC-B8 for 24102@debbugs.gnu.org; Fri, 05 Aug 2016 00:37:57 -0400 Original-Received: from pool-71-174-42-86.bstnma.east.verizon.net ([71.174.42.86] helo=jojen) by world.peace.net with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.84_2) (envelope-from ) id 1bVWtL-0002cR-Pg; Fri, 05 Aug 2016 00:37:51 -0400 In-Reply-To: <87a8grygyc.fsf@netris.org> (Mark H. Weaver's message of "Fri, 05 Aug 2016 00:31:39 -0400") X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 208.118.235.43 X-BeenThere: bug-guile@gnu.org List-Id: "Bug reports for GUILE, GNU's Ubiquitous Extension Language" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-guile-bounces+guile-bugs=m.gmane.org@gnu.org Original-Sender: "bug-guile" Xref: news.gmane.org gmane.lisp.guile.bugs:8332 Archived-At: Mark H Weaver writes: > As a result, some important properties of SRFI-111 boxes do not hold for > your proposed implementation. For example, in SRFI-111, (box? x) > implies that (box-ref x) will not raise an exception, and this fact can > be exploited by a compiler to produce better native code for 'box-ref' > when the type of its argument is known to be a box. In such cases, I > guess 'box-ref' can be implemented as a single load instruction, whereas > 'variable-ref' will require a conditional branch. s/box-ref/unbox/g Mark