need

   1 Action::RemoveValue
   2         BindValue
   3         SetBoundValue
   4         AddBoundValue
   5         RemoveBoundValue
   6 ActionBuilder::BoundValue
   7 ? KnownFactSet
   8 ? KnownResolutionSet
   9 Predicate::Foreach
  10 Predicate::Findall
  11 Predicate::Forall
  12 Predicate::Rule
  13 Predicate::Not
  14 Step::SubSolve
  15 Solution
  16 Endjinn