- From: <noah_mendelsohn@us.ibm.com>
- Date: Thu, 31 Jan 2002 16:31:27 -0500
- To: dbox@microsoft.com
- Cc: jacek@systinet.com, "Martin Gudgin" <marting@develop.com>, "XML Protocol Discussion" <xml-dist-app@w3.org>
Don Box suggests: >> I believe that one could express all section 5-isms (typed >> references, arrays) using idioms currently supported in schema + a >> handful of NS-qualified attributes. Yes, one can certainly do that, but I don't think it addresses the question of a schema language for the resulting graph model. It seems to me that a good schema language captures equivalence classes as well as validity. So the XML schema language can tell you that there's a sense in which the following are equivalent: <a xsi:type="xsd:integer">3</a> and <a xsi:type="xsd:integer">003</a> In the case of the encodings, I think you want a schema language that treats the following as equivalent: <b id="someid">hello</b> <a href="someid"> and <b id="someotherid">hello</b> <a href="someotherid"> and that understands that the graph edge named "a" is equivalent not only in the two examples above, but also for: <a>hello</a> In other words, these are all three cases in which the graph has an inbound edge named "a" with a value of "hello". I think that XML schema is the wrong level of description language in which to capture that equivalance. I would expect a description language for SOAP encoding to have primitives like "struct", "array", and perhaps some notion of typed node or edge (as opposed to element.) In short, I think that schema is constraining the serialization of the graph, not the graph itself, and that seems problematic to me. ------------------------------------------------------------------ Noah Mendelsohn Voice: 1-617-693-4036 IBM Corporation Fax: 1-617-693-8676 One Rogers Street Cambridge, MA 02142 ------------------------------------------------------------------
Received on Thursday, 31 January 2002 16:45:22 UTC