Re: Simple approaches to XML implementation

Tim Bray (tbray@textuality.com)
Sat, 01 Mar 1997 18:28:34 -0800

At 07:19 PM 01/03/97 +0100, F. Chahuneau - General Manager wrote:
>All in all, you can see that some design decisions in XML were precisely
>motivated by the desire to make an ESIS event stream sufficient to
>implement an identity transformation, even with no access to DTD
>information. This is, of course, totally consistent with the idea that DTDs
>should not be systematically needed for processing XML fragments.

Whereas I agree with the rest of Francois' contribution, this paragraph
is not quite right. If you change "ESIS event stream" to "Instance
character stream", then it would be more correct. But in fact the
SGML->SGML declaration was not one of our goals; for example, the
processor is not required to tell the app about [at least] comments
and <![CDATA[ sections. The XML spec says *nothing* about the ESIS,
merely, in a very abstract way, what the processor has to give the
application.

If either of these problems (the impossibility of SGML->SGML or the
absence of an ESIS equivalent) is a big huge flaw in XML, there's still
time to fix it. The SGML->SGML problem is probably a job for the
XML WG. The ESIS issue is perhaps a job for this list. I personally
think an API is better than an ESIS [even if the ESIS were properly
defined] anyhow.

Cheers, Tim Bray
tbray@textuality.com http://www.textuality.com/ +1-604-708-9592