From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: David Kastrup Newsgroups: gmane.emacs.devel Subject: Coding system robustness? Date: Fri, 18 Mar 2005 18:45:42 +0100 Message-ID: NNTP-Posting-Host: main.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: sea.gmane.org 1111168301 9622 80.91.229.2 (18 Mar 2005 17:51:41 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Fri, 18 Mar 2005 17:51:41 +0000 (UTC) Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Fri Mar 18 18:51:39 2005 Original-Received: from lists.gnu.org ([199.232.76.165]) by ciao.gmane.org with esmtp (Exim 4.43) id 1DCLd4-0005wP-2o for ged-emacs-devel@m.gmane.org; Fri, 18 Mar 2005 18:51:22 +0100 Original-Received: from localhost ([127.0.0.1] helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1DCLtb-00069v-4J for ged-emacs-devel@m.gmane.org; Fri, 18 Mar 2005 13:08:27 -0500 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1DCLrd-0005Aj-A8 for emacs-devel@gnu.org; Fri, 18 Mar 2005 13:06:25 -0500 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1DCLrV-00056k-6n for emacs-devel@gnu.org; Fri, 18 Mar 2005 13:06:17 -0500 Original-Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1DCLrU-00055Q-55 for emacs-devel@gnu.org; Fri, 18 Mar 2005 13:06:16 -0500 Original-Received: from [199.232.76.164] (helo=fencepost.gnu.org) by monty-python.gnu.org with esmtp (Exim 4.34) id 1DCLXh-0001hW-HR for emacs-devel@gnu.org; Fri, 18 Mar 2005 12:45:49 -0500 Original-Received: from localhost ([127.0.0.1] helo=lola.goethe.zz) by fencepost.gnu.org with esmtp (Exim 4.34) id 1DCLXg-0001Kb-67 for emacs-devel@gnu.org; Fri, 18 Mar 2005 12:45:49 -0500 Original-To: emacs-devel@gnu.org User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.0.50 (gnu/linux) X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org X-MailScanner-To: ged-emacs-devel@m.gmane.org Xref: news.gmane.org gmane.emacs.devel:34730 X-Report-Spam: http://spam.gmane.org/gmane.emacs.devel:34730 Hi, I'd like to know whether coding systems in general are supposed to be robust, meaning that decoding some random byte string into the coding system and reencoding it is guaranteed to deliver the same byte string again? Background for that question: I do error association in preview-latex (via AUCTeX) with the original source text, and generally unrobust transformations of the input may happen, such as splitting a multibyte-char in the middle, or translitering some of those chars, but not others. I currently work this by having the process use a raw-text encoding, replace potentially questionable stuff and reencode when it turns out that the contexts do not match the source file. This has the disadvantage that a) I need to go through the works even in case TeX is set up nicely enough to deliver mostly working characters, since the raw encoding will match much less often than a properly decoded stream. b) The displayed output looks like junk unnecessarily. If we are talking about multi-file documents written in different encodings, this problem is not possible to avoid with tolerable effort, but in the case where the encodings in one document match, it would be nicer to have AUCTeX have a nicer output buffer. So what encodings are expected to be "transparent" for what versions of Emacs (we are only interested in 21.3 and newer)? -- David Kastrup, Kriemhildstr. 15, 44793 Bochum