Re: [xacml] MAD conceptual model

[Erik Rissanen <erik@axiomatics.com>]

Tyson, Paul H wrote:
> However, there appears to be some motivation for defining it better in
> the Policy evaluation model, to allow more predictable xpath
> resource-ids to be generated for multiple decision requests, to
> facilitate regexp matching.  That is, the policy writer would be able to
> specify what namespace prefixes will be used, so that rules testing the
> string value of the xpath expression can be written without regard to
> the namespace binding used in the request.  I'm not terribly sympathetic
> with this, because I haven't seen a good XACML use case for it.  But on
> principle, any module that deals with xml namespaces ought to be free to
> define its own set of bindings to insulate itself from external changes.
>   

Paul,

There are possibilities in XPath to write expressions which do not use 
namespace prefixes at all.

For instance:

*[local-name()='Foo'][namespace-uri()='http://example.com/bar'][3]

(Pardon me if I got it slightly wrong. My Xpath skills are a bit rusty 
at the moment.)

Best regards,
Erik