FW: CAM Thoughts

Title: Message

From: Hipson,C,Chris,XSJ61 HIPSONC R 

Sent: 13 May 2004 15:16
To: Roberts,MME,Martin,XSG3 
R
Subject: CAM Thoughts

  

  
Hi 
  Martin

  
 

  
Having discovered that I can’t 
  post to the CAM list [bad attendance record I 
  guess J] I thought I’d run a few thoughts 
  by you.

  
 

  
Overall CAM looks nice although I imagine it 
  won’t fly well with existing schema fanatics J  [not 
  complex enough].

  
 

  
I like the way that CAM 
  provides ‘deterministic flexibility’ sidestepping the XML-Schema issue that a 
  flexible schema makes everything optional.

  
However assuming that users will start from existing 
  XML there appear to be some omissions?

  
1)      
  There is no 
  predicate support for namespaces.  [Yes I know you don’t like them but if 
  you need to meet existing XML documents half way then you’re going to need 
  this?]

  
2)      
  In XML-Schema 
  xs:all allows a ‘group’ of elements to appear in any order rather then in the 
  order listed. While I doubt there’s much demand for this in business documents 
  it would be very hard to reproduce in CAM without explicit support? So may 
  be worth adding?

  
 

  makeRecursive
  
Requires a StructureID which is only available as an 
  Advanced Option? But the predicate itself is not itself an Advanced 
  option?

  
“Donates that the specified 
  parent element can occur recursively as a child of this 
  parent.”

  
Does this mean that a block of XML could appear 
  anywhere in the tree under the 
  parent? 

  
This would seem excessively liberal and would prevent 
  any hope of building an XML-Schema from a CAM 
  template as David Webber would like to do?

  
Surely you need to have some ‘link’ from the point the 
  recursion is ‘inserted’ to the structure that is to be 
  ‘recursed’?

  
Or have a missed 
  something?????????

  
 

  
Packaging – trivial observation but the current vogue 
  [at least in web services J] is to try and 
  make large specs appear smaller by chopping them up!

  
In the case of CAM this might fly quite nicely as 
  CAM Base would equate to your 
  stuff and CAM Patterns and 
  CAM Repositories to 
  Davids?

  
 

  
How’s the selling process going with UBL?  Where 
  does it sit with respect to ebXML [which it obviously sits quite well with]? 
  And are you looking anywhere else?  ISO have for instance DSDL which is a 
  schema collective wrapped round XML Schema, RELAX NG, Schematron etc. etc. – 
  might offer some scope for feedback if nothing 
  else?

  
 

  
Cheers Chris 
  Hipson

  
Web Service Technology 
  Consultant

  
"If the facts don't fit the theory, change the 
  facts." Albert Einstein

  
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