Re: [xacml] xpath datatype and collision with the hierarchicalresources profile

Erik and All,

I am in favor of #4, modulo Daniel's information about nodeset absence 
in XPath 2.0.

Regards,
Anne

Erik Rissanen wrote:
> All,
> 
> Remember that we decided to include an explicit xpath datatype for 3.0
> to solve issues with namespace resolving in xpaths if they are
> represented by simple strings?
> 
> There is already a datatype called xpath-expression in the hierarchical
> resources profile. It does something completely different. It selects a
> nodeset from the <ResourceContent>.
> 
> When we introduce the new xpath datatype for 3.0, we have at least these
> alternatives:
> 
> 1. Call the new datatype ...-3.0-... and keep the existing datatype as
> well. I don't like this. I am worried about having two datatypes with
> almost identical names, except one called ...-2.0-... and the other
> ...-3.0-..., where they have completely different behavior.
> 
> 2. Give the new datatype a competely different name. The trouble here is
> that I cannot think of a good name. And it will look silly to have the
> old thing called "xpath-expression", although it isn't, and the new
> thing is called something else.
> 
> 3. Rename the datatype in the hierarchical resources profile. Call it
> "nodeset-by-xpath" or such.
> 
> 4. Drop the datatype in the hierarchical resources profile. It's not
> really a datatype, rather a function. Instead we define a function which
> takes an xpath as a parameter (in the form of the new 3.0 xpath
> datatype) and returns a nodeset selected from a <Content> document
> (indicated by a second parameter).
> 
> I prefer alternative 4. I think we need to break this in some way in any
> case since there is not a single <ResourceContent> anymore, so we need
> to add the second parameter to select the attribute category of the
> <Content> element. This makes the whole thing look even more like a
> function.
> 
> Regards,
> Erik
> 

-- 
Anne H. Anderson             Email: 
Sun Microsystems Laboratories
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