Re: MML charset tag regression

["Eli Zaretskii" <eliz@elta.co.il>]

> From: Dave Love <d.love@dl.ac.uk>
> Date: Sun, 25 May 2003 17:38:55 +0100
> 
>                        the Unicode branch doesn't actually deal with
> compound text properly, because it doesn't do extended segments, and
> the released version is at best pretty confused about that and I think
> not correct.  (Extended segments are not an extension to compound
> text, they're part of the specification, contrary to what the current
> code says.)

The support for extended segments was implemented as an extension of
ctext to avoid a thorough rewrite of the ctext en/decoder.  As you
know, the ctext encoder and decoder are variants of the iso-2022
en/decoder and are handled by the same code (in C).  At the time,
Handa-san recommended not to touch the iso-2022 code, saying that the
code was tricky and hard to maintain, and that we could inadvertently
break something important in the process.

The general idea of the current implementation (using post-read and
pre-write conversions) was also suggested by Handa-san.  As you might
expect, I gratefully accepted his expert opinions and suggestions.

That said, I personally won't object if someone would set forth
rewriting coding.c to have extended segments supported natively by the
iso-2022 code.  Please feel free.