Re: Revised language on: ISO/IEC 10646 -- another proposal

Albert Lunde (Albert-Lunde@nwu.edu)
Fri, 12 May 95 09:06:21 EDT

> I don't quite understand. The points (2) and (3) above seem to
> conflict. If I try to reformulate the explanation in my own words:
>
> 1. All characters used in the document that are in also the ISO
> 8859-1 repertoire must have the same code numbers as in ISO
> 8859-1.

Yes.

> 2. All characters used in the document that happen to be refered to
> by a numeric character entity must have the same code numbers as
> in ISO 10646.

Nope.

I'm using Dan's framework of talking about the SGML document
character set as a "coded character set" : a mapping from integers
to characters (unrelated to the MIME character encoding).

Thus, every character in the document character set, has
one or more code positions in this mapping, regardless of
if it actually appears in a numeric character reference.

Those code positions (or whatever we want to call them) determine
the value of numeric references to characters, but their
existence is not contingent on the actual use of numeric references.

For document character sets whose code domain and character range
_are_ a subset of ISO 10646 it is my intention that my
proposal be equivalant to the last proposal: the document
character set must be ISO 10646 or the restriction of it to
an appropriate subset of characters.

The special cases arise only if one wants to use characters
not in ISO 10646 or code positions unused in ISO 10646: this
is allowed but folks are warned to be careful of the consequences.

-- 
    Albert Lunde                      Albert-Lunde@nwu.edu