From mboxrd@z Thu Jan 1 00:00:00 1970 Path: main.gmane.org!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.devel Subject: Re: eight-bit char handling in emacs-unicode Date: 22 Nov 2003 18:53:05 -0500 Sender: emacs-devel-bounces+emacs-devel=quimby.gnus.org@gnu.org Message-ID: References: <200311130153.KAA04615@etlken.m17n.org> <200311130610.PAA04983@etlken.m17n.org> <200311130901.SAA05204@etlken.m17n.org> <200311140047.JAA06414@etlken.m17n.org> <200311180733.QAA13703@etlken.m17n.org> <200311190006.JAA14847@etlken.m17n.org> <200311210041.JAA18324@etlken.m17n.org> <200311210627.PAA18757@etlken.m17n.org> <200311220125.KAA20128@etlken.m17n.org> NNTP-Posting-Host: deer.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: sea.gmane.org 1069545358 32331 80.91.224.253 (22 Nov 2003 23:55:58 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Sat, 22 Nov 2003 23:55:58 +0000 (UTC) Cc: jas@extundo.com, emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+emacs-devel=quimby.gnus.org@gnu.org Sun Nov 23 00:55:55 2003 Return-path: Original-Received: from quimby.gnus.org ([80.91.224.244]) by deer.gmane.org with esmtp (Exim 3.35 #1 (Debian)) id 1ANhbX-0002bL-00 for ; Sun, 23 Nov 2003 00:55:55 +0100 Original-Received: from monty-python.gnu.org ([199.232.76.173]) by quimby.gnus.org with esmtp (Exim 3.35 #1 (Debian)) id 1ANhbW-0007jO-00 for ; Sun, 23 Nov 2003 00:55:55 +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 1ANiX2-0000QB-QJ for emacs-devel@quimby.gnus.org; Sat, 22 Nov 2003 19:55:20 -0500 Original-Received: from list by monty-python.gnu.org with tmda-scanned (Exim 4.24) id 1ANiWy-0000Nu-4w for emacs-devel@gnu.org; Sat, 22 Nov 2003 19:55:16 -0500 Original-Received: from mail by monty-python.gnu.org with spam-scanned (Exim 4.24) id 1ANiWS-0008RG-FL for emacs-devel@gnu.org; Sat, 22 Nov 2003 19:55:15 -0500 Original-Received: from [132.204.24.67] (helo=mercure.iro.umontreal.ca) by monty-python.gnu.org with esmtp (Exim 4.24) id 1ANiWS-0008RC-7R for emacs-devel@gnu.org; Sat, 22 Nov 2003 19:54:44 -0500 Original-Received: from vor.iro.umontreal.ca (vor.iro.umontreal.ca [132.204.24.42]) by mercure.iro.umontreal.ca (8.12.9/8.12.9) with ESMTP id hAMNr5bj026694; Sat, 22 Nov 2003 18:53:08 -0500 Original-Received: by vor.iro.umontreal.ca (Postfix, from userid 20848) id 905013C63E; Sat, 22 Nov 2003 18:53:05 -0500 (EST) Original-To: Kenichi Handa In-Reply-To: <200311220125.KAA20128@etlken.m17n.org> Original-Lines: 28 User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.3.50 X-DIRO-MailScanner: Found to be clean X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.2 Precedence: list List-Id: Emacs development discussions. List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+emacs-devel=quimby.gnus.org@gnu.org Xref: main.gmane.org gmane.emacs.devel:18042 X-Report-Spam: http://spam.gmane.org/gmane.emacs.devel:18042 >>> It is perfectly possible to live in such an environment >>> where only the charset iso-8859-1 is used but only the >>> coding system utf-8 is used. In this environment, the >>> results of encode-coding-string and string-make-unibyte are >>> of course not the same, but still both operations are >>> meaningful. >> I see that encode-coding-string does the utf-8 encoding, but what >> does string-make-unibyte do in such a case and what is it used for ? > It gets iso-8859-1 code-points of all characters in a > multibyte string and concatenate them (the same as what is > does in latin-1 lang. env.). You mean it does the same as (encode-coding-string str 'latin-1) ? Then why use string-make-unibyte ? > Please try C-x C-m L utf-8 RET and see how > string-make-unibyte and string-make-multibyte work. I'll try that, but I'd like to understand the motivation for making it work the way it works. I've always understood those two as "trying to DTRT" in a very ad-hoc way such that people that used to work in an 8bit non-ASCII environment don't need to worry about coding-systems and still have things working mostly correctly. Stefan