An Example From RuleML FOAF for query to possiblyKnows(Laura, Ben).




the Rule component (in POSL)

close2FOAF(?X) :- Q_knows(?X, ?Y), Q_FOAFPerson(?Y).
possiblyKnows(?X, ?Y) :- close2FOAF(?X), Q_FOAFStar(?Y).


the DL component (in RACER)

(in-knowledge-base datalogDL-t datalogDL-a)

(in-tbox datalogDL-t)
(signature :atomic-concepts (FOAFPerson FOAFFan FOAFStar)
 :roles((knowsWell :parent knows)
	(isKnownBy :inverse knows)
	)
 :individuals (Jing Jie Ben Laura))


(implies FOAFPerson (some knows FOAFPerson))
(equivalent FOAFFan (and FOAFPerson (all knowsWell FOAFPerson)))
(equivalent FOAFStar (and FOAFPerson (at-least 2 isKnownBy FOAFPerson)))

(in-abox datalogDL-a)

(related Jing Ben knowsWell)
(related Jing Jie knowsWell)
(related Jie Ben knows)
(related Jie Laura isKnownBy)

(instance Jing FOAFFan)