anchor.diff:    // Generate a checker based on an iterative deepening strategy
     // (If 'Invalid', a single random state walk is performed)
     Bool useIterativeDeepening;
  -  ID_Params id;
  +  // This must contain valid data if 'useIterativeDeepening' is 'True'
  +  ID_Params id; 
   
     // Number of testing iterations to perform. For iterative deepening,
     // this is the number of times to increase the depth before stopping
  
positive.code:   Reg#(Bool) testDone <- mkReg(False);
    List#(Bool) inState = stateConds(state, 1, freqs);
  
    // When count is 0 the checker is disabled
    Reg#(Bit#(32)) count <- mkReg(0);
    Bool enabled = count != 0;
  
negative.code:         gen;
        endrule
      end
  
    // Signal when all random generators have initialised
    rule initRandomGens;
      randGensInitialised <= all(tpl_1, randomGens);
    endrule
  
    // Generate rules to check invariant booleans.
    for (Integer i = 0; i < length(invariantBools); i=i+1)
  