Re: XML, HTML, SGML, life, the universe, and everything

At 02:58 PM 11/11/96 -0500, Steven J. DeRose wrote:
>At 10:36 AM 11/11/96 GMT, Charles F. Goldfarb wrote:
>>Conforming SGML means that any conforming system will produce the same
>>present, an XML document is not conforming SGML. 
>Well, not exactly ESIS, since ESIS isn't part of 8879. 
>Given that 8879 doesn't say what the result of parsing is, how do you tell
>whether a conforming system has done "the same thing" as another one has,
>*purely* given requirements of 8879? In 8879, a parser can be a black box
>that returns TRUE or FALSE (and maybe some error messages). For example, is
>there a normative definition for what it actually means to "ignore" an RE?
>If we take "ignore" at its English face value, then an SGML system which
>produces a byte-identical copy of its input is non-conforming -- it clearly
>doesn't ignore the REs that 8879 requires be ignored, so it violates 8879.
>What I'm saying is, if XML output falls so close to SGML's that nobody cares
>about the difference in practice, did we make a noise?

I think what needs to be done is to define a grove plan for XML.  Given
such a grove plan, it is then meaningful to say something like "using the
XML grove plan, an XML document parsed by an SGML parser shall produce a
grove identical to the grove produced by an XML grove construction process
using the same grove plan."

Note the connection to the syntax of the source: it's not enough simply to
have some arbitrary syntax from which you can construct an SGML grove: it
must be possible for an SGML parser to produce the same grove from the same

For example, the XML grove plan can exclude the "ignored markup" property,
thereby stating explicitly that "ignored" REs are in fact truly ignored, in
the sense that they will never be available to XML processors operating on
an XML document grove.

This would certainly provide a more precise definition than "ESIS".


W. Eliot Kimber (eliot@isogen.com) 
Senior SGML Consulting Engineer, Highland Consulting
2200 North Lamar Street, Suite 230, Dallas, Texas 75202
+1-214-953-0004 +1-214-953-3152 fax
http://www.isogen.com (work) http://www.drmacro.com (home)
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