svoid stepMaxWithPrintStruct(long maxSteps, Steppable s) {
  if (s == null) ret;
  long steps = 0;
  do {
    if (steps++ > maxSteps) break;
    printStruct(s);
  } while (s.step());
  printStruct(s);
}

svoid stepMaxWithPrintStruct(Steppable s, long maxSteps) {
  stepMaxWithPrintStruct(maxSteps, s);
}