import java.awt.*;
/**
* Prints (by appending) a list of Integers onto a TextArea AWT object.
* It does not clear the text area before writing to it.
* Returns null always.
*/
public class TextAreaPrint implements IFunAlgo
{
	private static TextAreaPrint _singleton = new TextAreaPrint ();
	public static IFunAlgo Singleton()
	{
		return _singleton;
	}

	private TextAreaPrint()
	{
	}

    public Object forEmpty(EmptyFW host, Object param)
    {
        return null;   // Nothing to print here.
    }

    public Object forCons(ConsFW host, Object param)
    {
      TextArea device = (TextArea) param;  // saves recasting all the time
		// appends the integer value of the data as a new line onto the TextArea
		device.append(host.car().toString() +'\n');
		return host.cdr().execute(this,device);  // recur on the rest of the list
    }
}