From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Chong Yidong Newsgroups: gmane.emacs.bugs Subject: bug#1723: 23.0.60; Odd behaviour with #'check-coding-systems-region Date: Thu, 15 Jan 2009 09:16:58 -0500 Message-ID: <87wscwmz6t.fsf@cyd.mit.edu> Reply-To: Chong Yidong , 1723@emacsbugs.donarmstrong.com NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: ger.gmane.org 1232029564 17885 80.91.229.12 (15 Jan 2009 14:26:04 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Thu, 15 Jan 2009 14:26:04 +0000 (UTC) Cc: Aidan Kehoe , 1723@emacsbugs.donarmstrong.com To: Kenichi Handa Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Thu Jan 15 15:27:15 2009 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.50) id 1LNTBY-0003mk-35 for geb-bug-gnu-emacs@m.gmane.org; Thu, 15 Jan 2009 15:27:04 +0100 Original-Received: from localhost ([127.0.0.1]:35637 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1LNTAH-0007ZN-H0 for geb-bug-gnu-emacs@m.gmane.org; Thu, 15 Jan 2009 09:25:45 -0500 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1LNT8C-0006c5-26 for bug-gnu-emacs@gnu.org; Thu, 15 Jan 2009 09:23:36 -0500 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1LNT87-0006XF-4g for bug-gnu-emacs@gnu.org; Thu, 15 Jan 2009 09:23:33 -0500 Original-Received: from [199.232.76.173] (port=49127 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1LNT86-0006Wn-QS for bug-gnu-emacs@gnu.org; Thu, 15 Jan 2009 09:23:31 -0500 Original-Received: from rzlab.ucr.edu ([138.23.92.77]:46570) by monty-python.gnu.org with esmtps (TLS-1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1LNT86-0004tN-7C for bug-gnu-emacs@gnu.org; Thu, 15 Jan 2009 09:23:30 -0500 Original-Received: from rzlab.ucr.edu (rzlab.ucr.edu [127.0.0.1]) by rzlab.ucr.edu (8.13.8/8.13.8/Debian-3) with ESMTP id n0FENQSH015912; Thu, 15 Jan 2009 06:23:27 -0800 Original-Received: (from debbugs@localhost) by rzlab.ucr.edu (8.13.8/8.13.8/Submit) id n0FEK3ZZ014629; Thu, 15 Jan 2009 06:20:04 -0800 X-Loop: owner@emacsbugs.donarmstrong.com Resent-From: Chong Yidong Resent-To: bug-submit-list@donarmstrong.com Resent-CC: Emacs Bugs Resent-Date: Thu, 15 Jan 2009 14:20:03 +0000 Resent-Message-ID: Resent-Sender: owner@emacsbugs.donarmstrong.com X-Emacs-PR-Message: followup 1723 X-Emacs-PR-Package: emacs X-Emacs-PR-Keywords: Original-Received: via spool by 1723-submit@emacsbugs.donarmstrong.com id=B1723.123202900314264 (code B ref 1723); Thu, 15 Jan 2009 14:20:03 +0000 Original-Received: (at 1723) by emacsbugs.donarmstrong.com; 15 Jan 2009 14:16:43 +0000 X-Spam-Bayes: score:0.5 Bayes not run. spammytokens:Tokens not available. hammytokens:Tokens not available. Original-Received: from cyd.mit.edu (CYD.MIT.EDU [18.115.2.24]) by rzlab.ucr.edu (8.13.8/8.13.8/Debian-3) with ESMTP id n0FEGfQh014252 for <1723@emacsbugs.donarmstrong.com>; Thu, 15 Jan 2009 06:16:42 -0800 Original-Received: by cyd.mit.edu (Postfix, from userid 1000) id D0C6757E221; Thu, 15 Jan 2009 09:16:58 -0500 (EST) X-detected-operating-system: by monty-python.gnu.org: GNU/Linux 2.6 (newer, 3) Resent-Date: Thu, 15 Jan 2009 09:23:33 -0500 X-BeenThere: bug-gnu-emacs@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.bugs:24159 Archived-At: It appears that check-coding-systems-region can return t under some circumstances, but this is not documented in the docstring, nor in the elisp manual. Could you update the documentation? Or, you can explain the circumstances under which this happens so that someone else can do the updating. Thanks. Aidan Kehoe wrote: > The check-coding-systems-region docstring says this: > > (check-coding-systems-region start end coding-system-list) > > Check if the region is encodable by coding systems. > > The value is an alist ((CODING-SYSTEM POS0 POS1 ...) ...), where > CODING-SYSTEM is a member of coding-system-list and can't encode the > whole region, POS0, POS1, ... are buffer positions where non-encodable > characters are found. > > If all coding systems in coding-system-list can encode the region, the > value is nil. > [...] > > It is unclear to me what "value" means there. My provisional > assumption was that it meant "return value", but that doesn't reflect > the behaviour of the function: > (with-temp-buffer (insert "a") (check-coding-systems-region > (point-min) (point-max) '(iso-8859-1))) > => t