Re: <sandro> PatHayes, can you formally define g-box for us?

On Thu, Oct 13, 2011 at 12:27 PM, Richard Cyganiak <richard@cyganiak.de>wrote:

> On 13 Oct 2011, at 05:31, Pat Hayes wrote:
> > REST defines a resource as a function from times to representations.
>
> Well, no, REST defines a resource as a a time-varying function from
> requests to representations.
>

Well, no, REST doesn't mention requests.

Fielding 5.2.1.1:

"...a resource *R* is a temporally varying membership function *M*R*(t)*,
which for time *t* maps to a set of entities, or values, which are
equivalent. The values in the set may be *resource representations*
and/or *resource
identifiers*. A resource can map to the empty set, which allows references
to be made to a concept before any realization of that concept exists -- a
notion that was foreign to most hypertext systems prior to the Web. Some
resources are static in the sense that, when examined at any time after
their creation, they always correspond to the same value set. Others have a
high degree of variance in their value over time. The only thing that is
required to be static for a resource is the semantics of the mapping, since
the semantics is what distinguishes one resource from another."



> > So, a g-box is a resource whose representations are (a recognized
> interchange syntactic form of) g-snaps, ie RDF graphs.
>
> That works.
>
> > IRI----HTTP/"identifies" ---- g-box
> > IRI----denotes/names-----g-snap
>
> That seems wrong. “Identifies” and “denotes” are distinct mechanisms, but
> it has always been the goal to align them wherever possible. The phrasing
> above seems to explicitly require that they are different – a URI
> “identifies” one thing but “denotes” another. That's bad.
>

Why is it bad if identify is not identical with denote?

Ian

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Ian Davis, Chief Technology Officer, Talis Group Ltd.
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