package  {
  /**
   * The interface that must be implemented by all observers of an
   * Observable object.
   */
  public interface actionscript_lib_util_Observer {
    /**
     * Invoked automatically by an observed object when it changes.
     * 
     * @param   o   The observed object (an instance of Observable).
     * @param   infoObj   An arbitrary data object sent by 
     *                    the observed object.
     */
    function update(o:actionscript_lib_util_Observable, infoObj:Object):void;
  }
}