[xacml] Re: [Model] Composition Use Case

> Matching of X500 Distinguished Names can not be handled via
> regular expressions (case, ordering of attribute-value
> assertions, handling of spaces, etc.).  URL's can not be handled
> via regular expressions (places where case matters versus where
> it does not).  Attributes that are themselves complex types (such
> as certain X509 Attribute Certificate attributes) can not be
> handled via regular expressions.

i can't speak to the x509 attributes but i am do not see your point on
regular expressions not being able to handle "case, ordering of
attribute-value assertions, handling of spaces, etc."  could you give me
an example of two things that are expressible in xml that i could not
differentiate between with something like grep?
 
> I don't think the language syntax itself can handle the matching
> rules for real-world sets of attributes.  I think the language
> must have a way of pointing to executables for handling the
> matching.

possibly, however unless you specify *precisely* how such an external
application will provide the desired match as part of the specification
you have effectively killed interoperability.

b