ResultSet
result variable: y
result variable: a
result variable: b
size: 2
solution: ResultSolution
  binding: ResultBinding
    variable: y
    value: http://rdf.hp.com/p
  binding: ResultBinding
    variable: a
    value: p1
  binding: ResultBinding
    variable: b
    value: v-a-1
solution: ResultSolution
  binding: ResultBinding
    variable: y
    value: http://rdf.hp.com/p
  binding: ResultBinding
    variable: a
    value: p2
  binding: ResultBinding
    variable: b
    value: v-a-2