Re: [www-xml-schema-comments] <none>

A key question is, do you want the "various processors" to be able to 
insert additional elements of the same name as those already present, e.g. 
a second  Customer element?  I believe that is the essence of the 
capability requested by other correspondents in this thread. 

You are asking for something different, I think:  the ability to use an 
<any> within an <all>.  Ironically, in the particular case you illustrate 
(where all of your elements are optional), that really corresponds to a 
completely unconstrained wildcard, which we do have already;  you are 
really asking us to validate any elements in any order, which we can do. 
What I don't think we can do is to validate an arbitrary mix of elements 
containing exactly one (or two, or three) <A/> one (or...) <B/>, but as 
many other unspecified elements as you like.

------------------------------------------------------------------------
Noah Mendelsohn                                    Voice: 1-617-693-4036
Lotus Development Corp.                            Fax: 1-617-693-8676
One Rogers Street
Cambridge, MA 02142
------------------------------------------------------------------------







"Prosi, Rainer 4620 PPE-WT" <Rainer.Prosi@de.heidelberg.com>
Sent by: www-xml-schema-comments-request@w3.org
10/16/00 02:45 AM

 
        To:     "'www-xml-schema-comments@w3.org'" <www-xml-schema-comments@w3.org>
        cc:     (bcc: Noah Mendelsohn/CAM/Lotus)
        Subject:        [www-xml-schema-comments] <none>

Hello All;

I am currently designing a specification for describing jobs in the print
industry (JDF - job definition format) that uses a hierarchical data model
that, in 
shorthand, looks like this:
<JDF>
  <Audits ?>
  <Customer ?>
  <Resources ?>
  <Links ?>
  <JDF*>
</JDF>
 The ordering of the elements is irrelevant, and since the data is 
supposed
to be modified by  various processors, which may append additional 
elements, it would be very convenient not to enforce any ordering, since 
the
ordering has no semantic value.
If no ordering is enforced, all you have to do is e.g:

DOM_Node links=JDF.GetNode("Links")
if customer.isNull() links=JDF.AppendNode("Links")

instead of writing of a loop that searches all predecessor children for 
the
last valid predecessor. IMO it is evident, that enforced ordering is an 
unnecessary burden in this case.

The other schema validable alternative is to define a child pool that
contains  multiple JDF childre e.g:
<JDF>
  <Audits ?>
  <Customer ?>
  <Resources ?>
  <Links ?>
  <JDFPool ?>
     <JDF*>
  </JDFPool>
</JDFl>

This is possible but seams to be a very formalistic solution to a problem
that can be solved simply by telling an XML Schema element that the 
ordering

of its children is arbitrary.

As a conclusion, I agree with Ivan, Michael and Martin that a construct 
that
allows unbounded elements in arbitrary ordering is desirable.

Rainer

Rainer Prosi
Heidelberger Druckmaschinen AG

Received on Monday, 16 October 2000 14:03:07 UTC