boolean test(Symbol buffer, Chunk bufferChunk, Instantiation inst) {
    boolean negated = (operator != null && operator.equals("-"));

    Symbol realSlot = (slot.isVariable()) ? inst.get(slot) : slot;
    if (realSlot == null) {
      // slot variable isn't defined yet, so save it in the instantiation to check later
      inst.addDelayedSlotCondition(buffer, this, bufferChunk);
      return true; // negated; // false;
    }

    Symbol bufferValue = bufferChunk.get(realSlot);
    if (bufferValue == null) return negated; // false;
    Symbol testValue = value;
    if (testValue.isVariable()) {
      if (bufferValue == Symbol.nil) return negated; // false;
      testValue = inst.get(testValue);
      if (testValue == null) {
        inst.set(value, bufferValue);
        return true;
      }
    }

    if (operator == null) return (testValue == bufferValue);
    else if (operator.equals("-")) return (testValue != bufferValue);
    else {
      double bufferNumber = Double.valueOf(bufferValue.getString());
      double testNumber = Double.valueOf(testValue.getString());
      if (operator.equals("<")) return (bufferNumber < testNumber);
      else if (operator.equals(">")) return (bufferNumber > testNumber);
      else if (operator.equals("<=")) return (bufferNumber <= testNumber);
      else if (operator.equals(">=")) return (bufferNumber >= testNumber);
    }
    return false;
  }
 /**
  * Gets a string representation of the slot condition with an instantiation if provided.
  *
  * @return the string
  */
 public String toString(Instantiation inst, Vector<Symbol> used) {
   String s = "      ";
   if (operator != null) s += operator + " ";
   s += slot + " " + value;
   if (inst != null && value.isVariable() && (used == null || !used.contains(value))) {
     Symbol v = inst.get(value);
     if (v != null) {
       s = String.format("%-35s", s);
       s += "[" + value + " <- " + v + "]";
     }
     if (used != null) used.add(value);
   }
   return s;
 }