package jp.ac.kobe_u.cs.prolog.lang;
/**
 * Implementing this interface allows an object to be pushed to trail stack.<br>
 * @see Trail
 * @author Mutsunori Banbara (banbara@kobe-u.ac.jp)
 * @author Naoyuki Tamura (tamura@kobe-u.ac.jp)
 * @version 1.0
 */
public interface Undoable {
    /** 
     * Undoes this object.<br> 
     * @see Trail#unwind(int) 
    */
    public void undo();
}