Re: "Semantics" vs. "No Semantics"

Gary Hallmark wrote:
>
> I agree that there are many ways to approach semantics.  While I'm not
> sure I would characterize model-theoretic semantics as more or less
> abstract than other approaches, I do fear that a model-theoretic
> semantics will be of little help
> to the implementors of RIF translators and associated rule engines. 
> Looking at other W3C formal semantic specifications for guidance, I
> find http://www.w3.org/TR/xquery-semantics/ to be a good approach. 
> Formal XQuery semantics are specified using RULES.  Why can't we
> specify RIF semantics using rules?  We could even write those rules
> using RIF.
>

Look, I do not want to start a religious war about "abstract semantics".
All what I mean is the following:

If S1 is a  semantics specifying more aspects of a language than a
semantics S2 for this language, then S1 is more abstract than S2.

This is the standard meaning of "abstract" in Computer Science.

Whether a model theopry helps or not implementi ng rule engines, is an
important issue. Many (among others myself) think that a model theory
helps avoiding implementations that diverge as of what they compute.

Implementations diverging on "how they compute" is good. Implementations
diverging on "what they compute" is bad. This is a common view in
stardizing.

All we need is a good way to properly specify the "what" and leave out
enough of the "how" for people to realize not only one implementations
but severla ones imporving over the foremr ones. Find suchy a good way,
and, I am confident, it won't be difficult to re-express ist as model
theory.

Another point: A Tarskian model theory is also specified using rules...

François

Received on Tuesday, 9 May 2006 08:38:52 UTC