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    <p>In short, you can't do this. Blank nodes are just another type of resource. Blank nodes act as existential variables in RDF; use of a blank node in a graph says that <em>some</em> resource exists and stands in certain relationships to other. For instance, the graph (with no blank nodes):</p> <pre><code>:x :hasPhoneNumber :phoneNumberList . :phoneNumbeList rdf:value "phone number 1", "phone number 2" . </code></pre> <p><em>entails</em> the following graph (with blank nodes):</p> <pre><code>:x :hasPhoneNumber [ rdf:value "phone number 1", "phone number 2" ] . </code></pre> <p>For more about this treatment, see <a href="http://www.w3.org/TR/rdf-mt/#unlabel" rel="nofollow">1.5. Blank Nodes as Existential Variables</a> from the W3C recommendation, <a href="http://www.w3.org/TR/rdf-mt/" rel="nofollow">RDF Semantics</a>.</p> <p>At the RDF and RDFS level, (where you'd be defining domains and ranges of properties) to distinguish whether a resource is a URI resource or a blank node. It's not really clear what it would <em>mean</em> either, if you could. By saying that</p> <pre><code>:p rdfs:domain :C ; rdfs:range :D . </code></pre> <p>what you're saying is that any time you see a use of <code>:p</code>, e.g., </p> <pre><code>:a :p :b . </code></pre> <p>that you can add the following triples to the graph:</p> <pre><code>:a rdf:type :C . :b rdf:type :D . </code></pre> <p>Notice since <code>rdfs:domain</code> and <code>rdfs:range</code> are about adding more triples to the graph, it doesn't really matter whether the subject and object of a triple using <code>:p</code> (<code>:a</code> and <code>:b</code> in this case) are blank nodes or URI nodes.</p> <p>If you want to have more than one phone number for a person, you could just use multiple triples, and have something like:</p> <pre><code>:p :hasPhoneNumber :phoneNumber1 , :phoneNumber2, :phoneNumber3 . </code></pre> <p>which is the three triples:</p> <pre><code>:p :hasPhoneNumber :phoneNumber1 . :p :hasPhoneNumber :phoneNumber2 . :p :hasPhoneNumber :phoneNumber3 . </code></pre> <p>Alternatively, if you want to model that a person can have some collection of phone numbers, you might use an RDF container. E.g., with an <code>rdf:List</code>:</p> <pre><code>:p :hasPhoneNumber ( :phoneNumber1 :phoneNumber2 :phoneNumber3 ) . </code></pre> <p>which can be written in full as </p> <pre><code>:p :hasPhoneNumber [ rdf:first :phoneNumber1 ; rdf:rest [ rdf:first :phoneNumber2 ; rdf:rest [ rdf:first :phoneNumber3 ; rdf:rest rdf:nil ] ] ] . </code></pre>
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