``An Active-Value-Spreadsheet Model for Interactive Languages''

Bradley T. Vander Zanden

In Languages for Developing User Interfaces, Brad Myers, ed., Jones and Bartlett Publishers, Boston, MA, 183-210, 1992.


The rapid evolution of interactive computing has not been accompanied by a similar evolution of languages to support this model. It is becoming increasingly evident that imperative languages are unsuitable for supporting the complicated flow-of-control that arises in interactive applications. This paper describes a declarative paradigm for specifying interactive applications that is based on the spreadsheet model of programing. This model includes multi-way constraints and action procedures that can be triggered when constraints change the values of variables. The action procedures provide support for structural constraints that describe structural relationships among objects. A number of examples are presented which show how multi-way and structural constraints can simplify the specification of certain types of graphical interfaces.