In a message dated 2001-09-24 20:50:25 Pacific Daylight Time,
[EMAIL PROTECTED] writes:
>> Does GB18030 DEFINED the mapping between GB18030 and the rest of 11 planes?
>> I don't think so, since Unicode have not define them yet, right ?
>
> Unicode defined all the planes, a long long time ago. It's added
> characters for 3 of them - Plane 1 (basically the overflow area for the
> non-CJK part of the BMP), Plane 2 (more ideographs) and Plane 14
> (special tag characters).
David's absolutely right. This is another common misconception, about
Unicode "not defining" the code space unless characters are actually assigned
to all the code points.
This kind of thinking led, in part, to all the complacency on the part of
database vendors and others concerning the need to support surrogate code
points. They thought that just because no characters had YET been assigned
to non-BMP code points, they could safely ignore the whole issue of surrogate
processing. Then, when non-BMP characters became a reality, we began to see
kludges like CESU-8.
-Doug Ewell
Fullerton, California
