# Pattern from SPARQL example:
#
# PREFIX foaf: <http://xmlns.com/foaf/0.1/>
# SELECT ?name ?mbox
# WHERE { ?x foaf:name  ?name ;
#           foaf:mbox  ?mbox .
#         FILTER isLiteral(?mbox) }

@prefix foaf: <http://xmlns.com/foaf/0.1/>.
@prefix gpt: <http://purl.org/vocab/riro/gpt#>.

[a gpt:Filter; gpt:onPattern
  [a gpt:Graph; gpt:allOf 
    ([a gpt:Statement;  gpt:subject _:x;  gpt:predicate foaf:name;  gpt:object _:name]
     [a gpt:Statement;  gpt:subject _:x;  gpt:predicate foaf:mbox;  gpt:object _:mbox])];
 gpt:valueConstraint
   [a gpt:ISLITERAL; gpt:arg1 _:mbox]].