import java.io.PrintWriter;
import java.io.BufferedReader;
import java.io.InputStreamReader;

/**
 * Some experiments to better understand Scheme Lists
 */
public class TestConsList
{
  public static void main(String[] args)
    throws EmptyListException
  {
    // Prepare input and screenput.
    BufferedReader keyboard = 
      new BufferedReader(new InputStreamReader(System.in));
    PrintWriter screen = new PrintWriter(System.out, true);

    // Create a list and print it out.
    SchemeList lst = new NullList();
    screen.println(lst);
    for (int i = 9; i > 0; i--) {
      lst = lst.addToFront(new Integer(i));
      screen.println(lst);
    }
    // Strange test: What happens if we add a list to its own front?
    lst = lst.addToFront(lst);
    screen.println(lst);
    // Repeatedly drop elements from the list.
    while (!lst.isEmpty()) {
      lst = lst.cdr();
      screen.println(lst);
    }

    // That's it, we're done.
    System.exit(0);
  } // main(String[])

} // class TestConsList