Sharpen.BitSet.Or C# (CSharp) Method

        public virtual BitSet Or(BitSet a)
        {
            BitSet s = (BitSet)this.Clone();
            s.OrInPlace(a);
            return s;
        }

 public BitSet GetDescendants(int rule)
 {
     BitSet descendants = new BitSet();
     descendants.Or(children[rule]);
     while (true)
     {
         int cardinality = descendants.Cardinality();
         for (int i = descendants.NextSetBit(0); i >= 0; i = descendants.NextSetBit(i + 1))
         {
             descendants.Or(children[i]);
         }
         if (descendants.Cardinality() == cardinality)
         {
             // nothing changed
             break;
         }
     }
     return descendants;
 }