*/
  public static void unsetPowerloomFeature(Keyword feature) {
    if (Logic.$CURRENT_POWERLOOM_FEATURES$.memberP(feature)) {
      if (feature == Logic.KWD_TRACE_SUBGOALS) {
        Stella.dropTrace(Cons.cons(Logic.KWD_GOAL_TREE, Stella.NIL));
      }
      else if (feature == Logic.KWD_TRACE_SOLUTIONS) {
        Stella.dropTrace(Cons.cons(Logic.KWD_TRACE_SOLUTIONS, Stella.NIL));
      }
      else if (feature == Logic.KWD_TRACE_CLASSIFIER) {
        Stella.dropTrace(Cons.cons(Logic.KWD_CLASSIFIER_INFERENCES, Stella.NIL));
      }
      else if (feature == Logic.KWD_CLOSED_WORLD) {
      }
      else if (feature == Logic.KWD_ITERATIVE_DEEPENING) {
        Logic.$ITERATIVE_DEEPENING_MODEp$ = false;
      }
      else if (feature == Logic.KWD_JUSTIFICATIONS) {
        Native.setBooleanSpecial(Logic.$RECORD_JUSTIFICATIONSp$, false);
      }
      else if (feature == Logic.KWD_JUST_IN_TIME_INFERENCE) {
        Logic.$JUST_IN_TIME_FORWARD_INFERENCEp$ = false;
      }
      else if (feature == Logic.KWD_EMIT_THINKING_DOTS) {
        Logic.$EMIT_THINKING_DOTSp$ = false;
      }
      else {
        { OutputStringStream stream000 = OutputStringStream.newOutputStringStream();

          stream000.nativeStream.print("`" + feature + "' is not a valid case option");
          throw ((StellaException)(StellaException.newStellaException(stream000.theStringReader()).fillInStackTrace()));
        }
      }
    }
    else {
      if (!Logic.$AVAILABLE_POWERLOOM_FEATURES$.memberP(feature)) {
        Stella.STANDARD_WARNING.nativeStream.println("Warning: No such PowerLoom environment feature: `" + feature + "'");
        Logic.printFeatures();
      }
    }
    Logic.$CURRENT_POWERLOOM_FEATURES$.remove(feature);
  }