``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.