code: @Override
      public List<? extends SatConstraint> buildConstraint(BtrPlaceTree t, List<BtrpOperand> args) {
          if (checkConformance(t, args)) {
              @SuppressWarnings("unchecked") Collection<Collection<VM>> s = (Collection<Collection<VM>>) params[0].transform(this, t, args.get(0));
              return s != null ? Collections.singletonList(new Split(s, false)) : Collections.emptyList();
          }
          return Collections.emptyList();
      }
docs: Build a constraint.
  
  @param args the parameters of the constraint. Must be 2 non-empty set of virtual machines.
  @return the constraint