anchor.diff:                seq
                   testDone <= False;
                   $display("=== Depth %0d, Test %0d ===", currentDepth, testNum);
  +                params.preStmt;
                   while (! testDone)
                     action
                       await(!waitWire);
  
positive.code: 
    // Display message when a chosen state is a no-op
    Bool showNoOp;
  
    // Generate a checker based on an iterative deepening strategy
    // (If 'Invalid', a single random state walk is performed)
  
negative.code:     BlueCheck_Params {
        showNonFire        : False
      , showNoOp           : False
      , preStmt            : seq delay(1); endseq
      , postStmt           : seq delay(1); endseq
      , iterativeDeepening : tagged Valid idParams
      , numIterations      : 3
      };
  