class TableSlice extends Relation {

  @Override
  public Table first(int nRows) {
    int count = 0;
    PrimitiveIterator.OfInt it = sourceRowNumberIterator();
    Table copy = table.emptyCopy();
    while (it.hasNext() && count < nRows) {
      int row = it.nextInt();
      copy.addRow(table.row(row));
      count++;
    }
    return copy;
  }

  public  TableSlice(Table table, Selection rowSelection);
  public  TableSlice(Table table);

}