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

Bob Jung (bobj@netscape.com)
Fri, 12 May 95 21:46:12 EDT

> 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.
>
> 3. Any remaining characters (i.e., those not in the ISO 8859-1
> repertoire and never occuring in the form of a NCR), may have
> arbitrary codes >255.
>
>Presumably the charset parameter of HTTP will be used to identify the
>mapping of (3).
>
>If this is correct, then this is awful! Where are clients going to get
>the mapping tables needed for (3)? Moreover, I don't see any practical
>way for the author to satisfy (2), except in the two trivial ways:
>either use ISO 10646, or don't use NCRs.

Bert raises a good point.
Supporting a full set of ISO 10646 NCRs for the various "charset" encodings
will require many large tables:
ISO-10646 to SJIS (and vice versa)
ISO-10646 to JIS (and vice versa)
ISO-10646 to EUC-JP (and vice versa)
ISO-10646 to GB (and vice versa)
ISO-10646 to HZ (and vice versa)
ISO-10646 to Big5 (and vice versa)
ISO-10646 to CNS (and vice versa)
ISO-10646 to KSC7 (and vice versa)
ISO-10646 to KSC8 (and vice versa)
ISO-10646 to ISO-8859-2 (and vice versa)
...
ISO-10646 to ISO-8859-10 (and vice versa)
ISO-10646 to KOI8 (and vice versa)
ISO-10646 to MacRoman (and vice versa)
ISO-10646 to MacCentralEuropean (and vice versa)
etc.

This is OK, as long as supporting NCRs > 255 is NOT required and FULL
conformance is attained by supporting ISO 8859-1 NCRs. (But if a browser
supports NCRs > 255, then they map to ISO 10646.)

Otherwise we are requiring a lot of additional resources to support a
feature that most people on this list have been saying will be rarely used.
Users still want browsers to run well on resource limited systems, so
requiring this for full conformance would be bad.

--
Bob Jung        bobj@netscape.com       +1 415 528-2688, fax +1 415 528-4122
Netscape Communications Corp.   501 E. Middlefield      Mtn View, CA   94041