[Versa] Question about query

[Uche Ogbuji]

On Thu, 2005-09-01 at 11:00 -0600, Michael Olson wrote:
> The following is a legal expression in Versa:
> 
>    <http://foo.com>
> 
> It can be used as a filter expression in a filter or traversal and it  
> returns a boolean value if the resource matches, etc.

Not currently.  You need eq(<http://foo.com>).  We did discuss predicate
vs pattern last month but I don't recall we ever settled on such a
change.


> My question, is what if this is the top level expression and executed  
> on an empty model.  What are the results of the expression?
> 
> Is it a boolean?
> 
> Is it null because the resource does not exist?
> 
> Is it just the resource's URI regardless of whether or not it exists?

Yes.

> I think it should be the empty set.

Why?


-- 
Uche Ogbuji                               Fourthought, Inc.
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