- From: Axel Polleres <axel.polleres@deri.org>
- Date: Wed, 13 Aug 2008 09:42:26 +0100
- To: kifer@cs.sunysb.edu
- CC: "Public-Rif-Wg (E-mail)" <public-rif-wg@w3.org>
Michael Kifer wrote: > As we discussed (a few months) earlier, binding patterns have no meaning > outside of a particular evaluation algorithm (procedural semantics). I remember well, but as long as this is not contradicting with the existing semantics - I guess for core, we can kind of assume a standard forward-chaining evaluation procedure, which only makes sense to me with binding patterns and safety - I see no problem with this. > It is > therefore not clear how to incorporate them in the current spec, which is > supposed to be independent of the procedural things. It would be only a part of the core dialect specification, which is just a syntactic restriction of BLD with the exact same semantics as BLD. Would you see a problem with that? Axel > michael > > On Tue, 12 Aug 2008 17:31:08 +0100 > Axel Polleres <axel.polleres@deri.org> wrote: > >> (put the subject under a [Core] label.) >> >> Binding patterns were mentioned a view times today, I thus try to >> reformulate here a definition, which may be a helpful starting point >> helpful in this context and which : >> >> An external predicate with external schema >> >> ( X_1,....,X_n; pred(X_1,....,X_n) ) >> >> is assigned with one or more binding patterns, where a binding pattern >> is a vector {in,out}^n: >> >> Any external predicate provides a way for deciding the truth value of an >> output tuple depending on the extension of a set of input predicates and >> terms. External predicates have a fixed interpretation assigned for >> their intended domains. The distinction between input and output terms >> is made in order to guarantee that whenever all input values of one of >> the given binding patterns are bound to concrete values, the fixed >> interpretation only allows a finite number of bindings for the output >> values such that the predicate evaluates to true, and those finite set >> of bindings which can be computed by an external evaluation oracle. >> >> If we agree to add something like binding patterns to DTB, I could start >> to "collect" the possible binding patterns for the DTB predicates. >> >> Side remark: note that external functions don't need binding patterns >> (obviously all parameters are 'in' and the only 'out' is the result.) >> >> Axel Polleres wrote: >>> Two pointers here... the notion of strong safety in hex-programs [1,2] >>> and Topor's considerations on safe database queries with arithmetics >>> [3] (cudos jos for the latter one) >>> >>> >>> 1. R. Schindlauer. Answer-Set Programming for the Semantic Web. PhD >>> thesis, Vienna University of Technology, Dec. 2006. >>> http://www.kr.tuwien.ac.at/staff/roman/papers/thesis.pdf >>> >>> 2. Thomas Eiter, Giovambattista Ianni, Roman Schindlauer, and Hans >>> Tompits. Effective Integration of Declarative Rules with External >>> Evaluations for Semantic Web Reasoning. In York Sure and John Domingue, >>> editors, Proceedings of the 3rd European Conference on Semantic Web >>> (ESWC 2006), Budva, Montenegro, number 4011 in Lecture Notes in Computer >>> Science (LNCS), pages 273-287. Springer, June 2006. >>> http://www.springerlink.com/content/f0x23wx142141v44/ >>> >>> 3. R. Topor. Safe database queries with arithmetic relations (1991) >>> Proc. 14th Australian Computer Science Conf >>> http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.48.4845 >>> >>> >> -- Dr. Axel Polleres, Digital Enterprise Research Institute (DERI) email: axel.polleres@deri.org url: http://www.polleres.net/ Everything is possible: rdfs:subClassOf rdfs:subPropertyOf rdfs:Resource. rdfs:subClassOf rdfs:subPropertyOf rdfs:subPropertyOf. rdf:type rdfs:subPropertyOf rdfs:subClassOf. rdfs:subClassOf rdf:type owl:SymmetricProperty.
Received on Wednesday, 13 August 2008 08:43:08 UTC