1. Slotted RuleML for Metarole-Based Object-Centered Knowledge Representation Harold Boley, NRC IIT e-Business 2 November 2002 Revised: 26 February 2005

2. 26-Feb-05 RuleML 0.88 1 Slotted RuleML Via the Name-Giving Metarole slot (I) Here is a self-explaining 'metarole' (slot) representation of the slotted, RDF-like Jess fact (automobile (make Ford) (model Explorer) (year 1999)) in Object-Oriented (OO) RuleML – part of RuleML 0.88 – with user slots named via the first subelement: automobile make Ford model Explorer year 1999

3. 26-Feb-05 RuleML 0.88 2 Slotted RuleML Via the Name-Giving Metarole slot (II) This 'Slotted RuleML' notation corresponds to the 'positionalized' ruleml-datalog notation automobile Ford Explorer 1999 if the 'roles' of the make, model, and year positions are remembered somewhere else (signature declaration)

4. 26-Feb-05 RuleML 0.88 3 Slotted RuleML Via the Name-Giving Metarole slot (III) Note that a mix of an ordered sequence of args and role-unordered args will thus be possible in facts as well: automobile Ford Explorer 1999 mileage 65000 color white Also, Ind elements can be replaced by (typed) Var elements in all of the positional, slotted and mixed notations

5. 26-Feb-05 RuleML 0.88 4 Flat Feature Terms in Slotted RuleML The minimal 'metarole' (slot) representation of the slotted, RDF-like (untyped) feature term, similar to F-logic term, auto[make -> Ford; model -> Explorer; year -> 1999] in RuleML 0.88 with user slots named via the first subelement: auto make Ford model Explorer year 1999 Can also be used as an argument in facts

6. 26-Feb-05 RuleML 0.88 5 Nested Feature Terms in Slotted RuleML The representation of the nested (untyped) feature term vehicle[winter -> auto[make -> Ford; model -> Explorer; year -> 1999] summer -> cycle[make -> Honda; model -> Magna; year -> 2002]] in RuleML 0.88 with user slots named via the first subelement: vehicle winter auto make Ford model Explorer year 1999 summer cycle make Honda model Magna year 2002