RE: [emergency] Re: Circle and Polygon

["Bullard, Claude L (Len)" <len.bullard@intergraph.com>]

Your analysis is correct, Winnie.  I'm a wonk from the 
days when ISO 8879 was a draft and fought in the 
"HTML didn't get it all right" wars.  Forgive me 
for being tendentious.  Given the choices at the 
time, XSD was the right technology.  If done over 
again, I'd take a hard look at alternatives such 
as RELAX NG and Schematron, and the new ISO standards 
for this.  

<offtopic>
Atts are typically used for the domain or for singleton 
primtive types such as ID that the XML processor must enforce. 
Precisely as you say.  Avoiding attributes is one of those myths 
propagated in the early part of the XML development 
when the parserGorillas dominated the savannah.  It's 
an old and well documented topic.  They do create an 
impedance mismatch with object-oriented systems that 
serialize and deserialize if the developer wrongly 
believes that object fields and element attributes 
are isomorphic.  It was a major stumbling block for 
X3D specification work because it took the OOPMen 
a very long time to accept that.  VRML was a pure 
object-oriented design.   Where rendering and 
behavioral fidelity are equally important, the 
markup design has to be subordinate to the object 
design.  It isn't unusual to find multiple encodings 
for those kinds of specs.
</offtopic>

len


From: Winfield Wagner [mailto:wwagner@crossflo.com]

Claude Bullard:

You are correct on your analysis.  You have to forgive me on the fact
coming from the GJXDM world I have been brain washed into thinking XSD.
Before my GJXDM days and today I would use the attribute method for
solving the reference system identity situation. It is describer for the
domain of the element not a real world element in itself.  This has been
a very sticky point in GJXDM.  Many of elements are descriptive
variations that define a context of an element (how it is referenced in
a domain) rather than a real world element.