assertTrue(model.isBoundFactUsed("x"));
assertFalse(model.isBoundFactUsed("y"));
assertEquals(3, model.lhs.length);
assertFalse(model.removeLhsItem(0));
assertEquals(3, model.lhs.length);
final ActionRetractFact fact = new ActionRetractFact("q");
model.rhs[0] = fact;
assertTrue(model.isBoundFactUsed("q"));