RE: [xacml] proposal for AttributeValue element to support sequen ceof values.

Currently <attributeValue> element is an 
extension of anyType, with specified DataType.

XACML 
functions arguments are, in general, a sequence of typed elements - as it can be 
returned by a designator from context.  While most accept only single 
values (sequence of size 1), some set operation functions have an arbitrary 
length sequence as an argument.

We 
need to provide syntax to express a sequence of values as a literal argument in 
set operations (like union, member_of, intersection..)

 

I 
propose adding element Value, of anyType, and defining 
<AttributeValueType> as sequence of <Value>, with DataType 
attribute, applicable to all elements 

in the 
sequence.  It supports 0 size of the sequence, to support empty set in 
operations

 

 <xs:element name="Value" 
type="xs:anyType"/>
 <xs:element 
name="AttributeValue"/>

<xs:complexType 
name="AttributeValueType">
  <xs:sequence minOccurs="0" 
maxOccurs="unbounded">
    <xs:element 
ref="Value"/>

  
</xs:sequence>

   <xs:attribute 
name="name" type="xs:anyURI" 
use="required"/>
 </xs:complexType>