[Versa] More on literal queries

[Uche Ogbuji]

On Tue, 2005-09-13 at 13:45 -0400, Chimezie Ogbuji wrote:
> > Just to be clear, your not talking about a "context" as shown in the
> > above EBNF correct?  In the EBNF, context is the ".".  I've been trying
> > to talk about the "scope" of an expression which I think is what you
> > mean.
> 
> I should be explicit.  When I said context, I mainly meant the idea of
> a subgraph (possibly named).  But there are three interpretations, as
> I see it:
> 
> - Context:  A named subgraph In the pure RDF sense (the scope
> attribute on 4RDF Statements)

Yes, what we call "scope" (the name I picked based on Topics Maps
usage).  But now that the RDF community is converging on "context", this
is the term we should use for Versa.

> - Versa Context:  Consisting of a core data type, variable bindings,
> namespace declarations, and a named Context (subgraph)

This to me is "query state".

> - The '.' Expression: Shorthand for the the data type instance
> associated with the current Versa Context

Personally, I think we lose this entirely, based on the other
conversation on anonymous, first class functions.

> So, { .. } would be a 'Context expression' which resolves to an
> anonymous Context (subgraph), which will then be associated with the
> Versa context used to evaluate the scoped expression that follows in:
> 
> { .. } <scoped expression>

I suppose so.


-- 
Uche Ogbuji                               Fourthought, Inc.
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