package scheme2.visitor;

import scheme2.AListFW;
import scheme2.IListAlgo;

public class Length implements IListAlgo
{
	/** @SBGen Singleton Variable   */
	public final static Length Singleton = new Length ();

	/** @SBGen Constructor   */
	private Length()
	{
	}

	/**
	 * @param host 
	 * @param input not used
	 * @return 
	 */
	public Object forEmpty(AListFW host, Object input)
	{
		return new Integer (0);
	}

	/**
	 * @param host 
	 * @param input not used
	 * @return
	 */
	public Object forNonEmpty(AListFW host, Object input)
	{
		return new Integer (1 + ((Integer)host.getRest ().execute (this, null)).intValue ());
	}
}