XML Union type problem

[Amila Suriarachchi]

hi,
Can we use a simple type union as an attribute type? in other words is the
following xmlSchema fragment correct?

 <s:simpleType name="TestUnion">
       <s:union memberTypes="s:string s:int"/>
   </s:simpleType>

   <s:complexType name="TestUnionElement">
       <s:attribute type="s0:TestUnion"/>
   </s:complexType>

if so what could be the serialized xml pattern?

I recently implemented the Union type support for adb.
For a example Lets take following schema fragment

   <s:simpleType name="FooOpenEnum">
       <s:union memberTypes="s:int s:string"/>
   </s:simpleType>

<s:element name="Record1">
       <s:complexType>
           <s:sequence>
               <s:element name="elem1" type="s0:FooOpenEnum"/>
           </s:sequence>
       </s:complexType>
   </s:element>

for the above schema part the serialized xml is as follows

<Record1>
        <elem1 xsi:type="xs:string>teststring</elem1>
</Record1>

does this xsi:type="xs:string part manadatory? (I think so)

Can someone comment on this?

Amila.

--
Amila Suriarachchi,
WSO2 Inc.