Design of VACL: a visual script language system which controls and extends applications on a graphical user interface environment

We are constructing a new visual script language system called VACL (Visual Application Control Language). The purpose of this script language system is to perform batch operations efficiently in a graphical user interface (GUI) environment and to extend GUI applications. This system represents a script program as a `post-it´ (or `fusen´) on a display. A user can launch a script program by attaching a fusen on to the window of the appropriate application. We call this kind of execution mechanism a `fusen metaphor´. This script language system has four major benefits. First, the script program to control an application can be written transparently from the application and in a highly abstract manner. Second, a script program that extends an application can be written transparently from the application. Third, the fusen metaphor enhances the reusability of the script program and provides a hypertext programming environment. Fourth, by describing the script program visually, the programmer can describe a 2D GUI application object in a natural and easy form