[Versa] Issue 3

[Michael Olson]

>>
>> Maybe a slight modification to the query like
>>
>> some_node -* all() -> eq(.'foo')
>>
>> Which kind of leads to:
>>
>> expression - expression -> filter     --> results in object
>> expression -| expression -> filter   --> results in subject
>> expression -* expression -> filter    ---> results in statement
>> expression -& expression -> filter    ---> results in predicate????
>
> So, 1 and 2 we have already.  3 would require promoting statements to
> first class Versa datatypes (which I think would have benefits - but
> how would statement data types work with the other data types for
> conversion to and from, etc..).  4 would just be an extension of the
> traversal syntax and would solve the original problem.
>

What if statement datatypes were the results of a traversal?  Then  
different functions to convert to the different pieces of the  
statements.

subject(* - rdf:type -> rdf:Property)   would be the set of all  
resources in the system that are properties.




> I think if you promote statements to first class objects then you also
> expose statementUri's and Scopes/Context to Versa.  Currently I can
> only expose (or filter by) scopes with the explicit use of a scope
> function, however if you model statements as first class objects with
> the following properties:
>

Just wanted to add that context/scope are 4RDF'isms so they should be  
extension functions to versa.

Mike


> - subject
> - predicate
> - object
> - statementUri
> - context/scope
>
> You can kill two birds with one stone.  But what would be the
> semantics of working with statements as objects.  What would be the
> kinds of things you would want to do with statements as a whole (as
> opposed to just their parts)?
>
>>
>> This means that statement would need to be added as a data type.  with
>> conversion and a set of functions......
>
> Ya...
>>
>> Mike
>>
>>
>> ---------------------------------------------------------------------- 
>> --
>> -----------------
>> Mike Olson                                                Principal
>> Consultant
>> mike.olson at fourthought.com                +1 720 253 4662
>> Fourthought, Inc.
>> http://Fourthought.com
>> PO Box 270590,                                       http://4Suite.org
>> Louisville, CO 80027-5009, USA
>> XML strategy, XML tools, knowledge management
>>
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>>
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------------------------------------------------------------------------ 
-----------------
Mike Olson                                                Principal  
Consultant
mike.olson at fourthought.com                +1 720 253 4662
Fourthought, Inc.                                       
http://Fourthought.com
PO Box 270590,                                       http://4Suite.org
Louisville, CO 80027-5009, USA
XML strategy, XML tools, knowledge management