Hi folks,

This is to try to pick up on the issue identified by Suman in today’s call.

The Issue

Consider the following example:

<xs:element name="root">

<xs:complexType>

                                <xs:sequence>

                                                <xs:annotation><xs:appinfo source=”http://dataformat.org” />

                                             <hidden>                                                                

                                                                                <xs:element name="repeats" type="xs:integer"/>

                                                                </hidden>

                                                </xs:appinfo></xs:annotation >

                                <xs:element name="testElement" type="xs:integer " minOccurs=”0” maxOccurs=”unbounded”

 dfdl:repeatCount=”../repeats”>                                                                                                                                      

                </xs:complexType>

</xs:element>

The problem is that the path “../repeats” can be broken by modifications to the logical model due to name clashes on “repeats” and there are cases that can be constructed where this would not be obvious to a user.

Possible Solutions

Possible fixes to this include:

1. Disallow XPath references to hidden elements the user is forced to place the material into the global context to refer to it.
2. Provide a special XPath operator to indicate we are referencing a hidden element, possibilities include:
1. “../hidden(repeats)”
2.  “hidden(../repeats)”
3.  “../dfdl:hidden/repeats”
3. Only allow hidden elements to be present in top level global complex types. These can then be included where needed. (This is the solution that Suman was pushing but I don’t fully understand it – in particular I don’t see how it resolves the ambiguity issue.)

I believe my preference here is 2a or 2b followed by 1.

Comments/suggestions/opinions?

Thanks,

Martin