Hang on... you're talking about non-western writing systems inside
attribute values? I hope not. I don't expect the _syntax characer
set_, i.e. the coded character set used for markup (including
attribute value literals) of HTML ever to be anything other than ISO
646 IRV (aka 7 bit ASCII).
Why do you think that attribute value literals should be limited to
the concrete syntax charset?
If you really believe that non-ISO-646 characters should be excluded
from attribute value literals, then you'd better redesign HTML to provide
another way to specify all of the following attributes:
<ATTLIST META
NAME ...
CONTENT ...
<ATTLIST LINK
TITLE ...
<ATTLIST A
TITLE ...
<ATTLIST IMG
ALT ...
<ATTLIST INPUT
NAME ...
VALUE ...
<ATTLIST SELECT
NAME ...
<ATTLIST OPTION
VALUE ...
<ATTLIST TEXAREA
NAME ...
Since I suspect you don't want to do this, get used to assuming that
non-ASCII will appear in attribute value literals. In any case, it
may be desirable to extend the concrete syntax charset to include
additional SEPCHAR and FUNCHAR characters from 10646.
Regards,
Glenn