Making Statements About the Items in a Container

You can also make statements about each item in a container by using the container's aboutEach attribute. For example, suppose that I want to indicate that each item in a bag has the same creation date. In that case, I could assign the value " creationDate " to the Bag's aboutEach attribute and add a new <rdf:Description> element about "#creationDate" , like this:

Listing ch18_15.rdf

 <?xml version="1.0" ?> <rdf:RDF     xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"     xmlns:dc="http://www.purl.org/DC#">     <rdf:Description about="http://www.starpowder.com/planets.html">         <dc:Title>Mercury</dc:Title>         <dc:Creator>Nicolas Copernicus</dc:Creator>         <dc:Subject>  <rdf:Bag aboutEach="creationDate">  <rdf:li                     resource="http://www.starpowder.com/mercury.html"/>                 <rdf:li             resource="http://www.starpowder.com/venus.html"/>                 <rdf:li                     resource="http://www.starpowder.com/earth.html"/>                 <rdf:li                 resource="http://www.starpowder.com/mars.html"/>             </rdf:Bag>         </dc:Subject>     </rdf:Description>  <rdf:Description aboutEach="#creationDate">   <dc:Date>   1501-10-15   </dc:Date>   </rdf:Description>  </rdf:RDF>