VisaVis-contributions to practice and theory of highly interactive visual languages

Higher-orderness, highly interactive, a great amount of flexibility, color, increasing the visual extent and parallelism are all catchwords related to the development of visual languages. The paper reports on the functional visual language VisaVis coming up with a new user interaction strategy integrating higher order functions smoothly. VisaVis uses colors and shadows to convey information about the degree of interaction. A comparison with existing visual languages is presented to picture reached results to the reader. The translation into a meta-language which preserves inherent parallelism in a visual program is outlined. Additionally the concept of an implicit type system is introduced being sound and complete which prepares for prevention of run-time errors and increases the visual extent at the same time