// Allows to vary the order by supplying a seed
//
// We add the seed to every LSFR value generated, and also start
// the LSFR with the seed.

sclass WeightlessShuffledIteratorWithSeed<A> extends WeightlessShuffledIterator<A> {
  final int cycleLength, offset;
  
  // initialize only with a length (and a pseudo-list)
  // if you are going to be calling nextIndex() instead of next()
  *(int n) {
    this((L) virtualNullList(n));
  }
  
  *(int n, int seed) {
    this((L) virtualNullList(n), seed);
  }
  
  *(L<A> list) {
    this(list, 0);
  }

  *(L<A> list, int seed) {
    super(list);
    if (lsfr == null) { cycleLength = offset = 0; ret; }
    lsfr.start(seed);
    cycleLength = lsfr.cycleLength();
    offset = lsfr.value-1;
    printVars ifdef WeightlessShuffledIterator_debug(+seed, +cycleLength, +offset, start := lsfr.value);
  }
  
  int postProcessLSFRValue(int i) {
    i += offset;
    ret i >= cycleLength ? i-cycleLength : i;
  }
}

Began life as a copy of #1035207