Re: Lack of a standard rules language Re: Toward easier RDF: a proposal

On Mon, 2018-11-26 at 03:13 -0500, David Booth wrote:
> On 11/25/18 1:34 PM, Paul Tyson wrote:
> > On Thu, 2018-11-22 at 14:47 +0000, Nathan Rixham wrote:
> >> Yes, N3 immediately addresses multiple points from the opening thread.
> >>
> >> It's a great starting (and ending?) point, to this
> > 
> > The original defect report ("Lack of a standard rules language") is
> > wrong. RIF has been in the SemWeb stack for a long time. 
> But RIF is *not* a rules language, AFAIK.  It is a rules *interchange* 
> format, to allow various different rules languages to be exchanged.  As 
> the first sentence of the Introduction of the RIF Overview clearly states:
>    "The Rule Interchange Format (RIF) . . . [is] a standard
>    for exchanging rules among rule systems, in particular
>    among Web rule engines. RIF focused on exchange rather
>    than trying to develop a single one-fits-all rule language
>    because, in contrast to other Semantic Web standards, such
>    as RDF, OWL, and SPARQL, it was immediately clear that a
>    single language would not satisfy the needs of many popular
>    paradigms for using rules in knowledge representation and
>    business modeling."
> Am I missing something?

Yeah, that gave me pause, but I tried it out and it worked for my
purpose. I can only guess those words were added for political reasons,
to mollify participants with a stake in other rule languages. RIF is a
rules interchange language in much the same way XML is a document
interchange language. My alternatives were RuleML and Common Logic, both
excellent creations, but RIF is tightly integrated with semweb stack.

In my application, the "interchanges" were rif2html (for documentation)
and rif2sparql (for runtime execution). But I can imagine rif2sql,
rif2prolog, rif2n3, rif2[your-favorite-enterprise-app] and any number of
specialized analysis and documentation tools. Try that with N3 source.

> > It has of
> > course been largely ignored while practitioners invent special-case
> > solutions.
> Why has it been ignored?  It would be useful to learn.

I don't know. Social and market forces, I guess, in addition to
ignorance. Why an enterprise would bury so much of its crucial business
logic in proprietary formats is beyond my understanding.


> > RIF is directly compatible with XML, RDF, and OWL, which means you have
> > a lot of basic tooling to process it. It covers practically all rule
> > styles anyone would want, and includes a standard extension mechanism.
> > 
> > My only complaint about RIF is that, due to timing of the working
> > groups, it is not fully interoperable with SPARQL. Also for the same
> > reason, there is some disconnect between RIF datatypes and built-ins,
> > and the XSD datatypes and xpath functions. It's been quite a while since
> > I worked in this area so I don't recall the details.
> > 
> > That should be the starting point on this topic: re-open a working group
> > on RIF to make it capable of expressing SPARQL constructs, and resolve
> > the datatype and built-in discrepancies with other W3C specs.
> Suggestion noted.  But if you think RIF should fill this need then it 
> would be wise also to understand why RIF has not had broader uptake already.
> Thanks,
> David Booth

Received on Thursday, 29 November 2018 01:10:55 UTC