[xsd-users] cpp-parser nested elements/attributes

[Kevin Wooten]

I have either misunderstood how to setup a cpp-parser or it seems to be 
quite broken. During parsing, the "event_router" object will search the 
tree starting at the root element and traverse downwards through the 
current scope, each time a new element starts. This means that elements 
and attributes with the same names are always handled incorrectly in 
elements above them in the scope.

Here is an example:

---- Schema ----
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
    <xs:complexType name="Sub">
        <xs:sequence>
            <xs:element name="sub" type="Sub" minOccurs="0"/>
            <xs:element name="sub2" type="Sub" minOccurs="0"/>
            </xs:sequence>
        <xs:attribute name="name" type="xs:string" />
        </xs:complexType>
   
    <xs:complexType name="Test">
        <xs:sequence>
            <xs:element name="sub" type="Sub" />
            </xs:sequence>
        </xs:complexType>
   
    <xs:element name="test" type="Test" />
</xs:schema>

----- XML -----

<test name="testName">
        <sub name="subName">
            <sub name="nestedName" />
            <sub2 name="sub2Name" />
        </sub>
</test>


In this case when starting the first "sub" element the event router will 
ask "test" if it can start the element. It can and does. When the second 
sub element is started, the event_router again ask the "test" element if 
it can start the "sub" element. It can and does, totally screwing the 
parsing. What it needs to do is ask only the current scope if it can 
start "sub" element, since it is the only valid place to start a new 
element in. To demonstrate how it will work 'sometimes', when starting 
the "sub2" element, the event_router still does the incorrect thing, but 
since "test" cannot start a "sub2" element, it continues trying the 
first "sub" element which succeeds. It is at this time you will see the 
attribute problem, because attributes are handled in the same way as 
elements. All the "name" attributes in this example will be handled by 
the "test" element parser.