// Iterate over all worksheets
for (w in M.worksheets) {
  w.name.println();

  // Iterate over all columns
  // of the worksheet
  for (c in w.header.columns) {
    c.name.println("\t");
  }

  // Iterate over all rows
  // of the worksheet
  for (r in w.rows) {
    r.println("\t");
  }
}