xml-dev - Re: An issue?: Parsers with XML Schema support & reporting errorsininval

[Rick JELLIFFE <ricko@geotempo.com>]

Dylan Walsh wrote:
  
> Perhaps there is a need for a formal or ad hoc standard for this reporting,
> e.g. an extension to SAX, that specifies subclasses of SAXParseException for
> different schema errors. Or is this already being dealt with?

There is something else that needs to be checked.  

After processing a document using a schema, the information set is
augmented
by various items: type, etc.    Different processors can augment the
infoset with different items, depending on what the application needs.

But there are three+ issues that need to be addressed AFAIK before there
can
be a SAX version of the PSVI (post-schema-validation infoset, doncha
love it)

 *  how to represent error and validity conditions (as Dylan mentioned)
 *  how to represent PSVI items that do not have any (possible) markup 
    equivalent:  for example, the type of an element can be expressed
    by adding an xsi:type attribute to the sax stream, but what can be
    used to express the type of an attribute? 
 *  does there need to be a special handling in SAX for element with
    the xsi:null attribute  (probably not)

So a post-schema-validation version of SAX may need to add arbitrary
properties on existing information items.  I wonder what people think
the best approach for handling this might be?

Rick Jelliffe