From 33d92c1f9de704cda9309731b4d6add46178aafc Mon Sep 17 00:00:00 2001 From: "Eric S. Raymond" Date: Mon, 22 Mar 1993 03:00:23 +0000 Subject: [PATCH] Merged in CHARACTERS --- etc/TO-DO | 57 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+) diff --git a/etc/TO-DO b/etc/TO-DO index cc5b398eec..e5b9a49599 100644 --- a/etc/TO-DO +++ b/etc/TO-DO @@ -24,3 +24,60 @@ Things useful to do for GNU Emacs: inverse video. * VMS code to list a file directory. Make dired work. + +Long range: + + Ideas for extending GNU Emacs to deal with arbitrary character sets. + +I would like GNU Emacs to be extended to handle all the world's alphabets +and word signs. I don't expect to have time to do such a thing in the next +few years, so here are my ideas on the best way to do it. + +* Each graphic is represented by a sequence of ordinary 8-bit characters. + +* All the characters that make up such a sequence have codes >= 0200. + +* The first character of such a sequence is between 0200 and 0237. + +* The remaining characters of such a sequence are all 0240 or higher. + +* The first character of the sequence determines the number of characters +in the sequence. Thus, 0200...0207 could start two-character sequences, +0210...0227 could start three-character sequences, and 0230 could start +four-character sequences. (Codes 0231...0237 would be reserved.) + +* Several common alphabets, and some mathematical symbols, would get +two-character sequences. (Probably Greek, Russian, Hebrew(?), Arabic(?), +Korean, and Japanese kana). The remaining alphabets, and some versions of +Chinese, would get three-character sequences. Other sets of Chinese +characters would get four-character sequences. + +Each country that uses Chinese characters has its own standard character +set, and it is not easy to correlate them to avoid overlap. So there may +need to be several sets of Chinese characters. That is why they need so +much code space. + +True support for Hebrew and Arabic requires dealing with the problem of +writing direction for mixed text; I don't know what to do for that. + +* The functions that use syntax table would determine the +syntax of a sequence from its first character. + +* Functions in indent.c for computing widths and columns would +determine the width of a sequence from its first character. +So would display routines. + +* Only a few other editing routines would need any change. In +particular, searching and regexp matching might not need any change. + +* Most of the work required would be in redisplay. The only case that +needs to be supported is with X windows, since ordinary terminals +can't display all these characters anyway. + +* There might need to be code to translate files from this format +to whatever format is typically stored on disk. + + +I would be very unhappy with half-measures, such as support for +Japanese only. + -- 2.20.1