Archetype-oriented CHI A formal Approach to User Friendliness

Abstract

Theoretical computer science has the aim of formalizing previous empiri- cal, innovative creations in computing. The possibility of automatically con- structing instances of such creations is dependam on the existence of formal models. This is panicularly true in computing since computers do not manipulate informal models of problem-solutions. This paper describes an exercise in using constructive and algebraic specifica- tions in the formalization of some aspects of computer-human interaction (CHI). Formal specification can not only contribute to a better understanding of CHI, but also provide the almost non-existent link between CHI and Software Engineering. In this paper, from a modest analysis of user behaviour, we build mathematical models which lead to a formalization of the "standard" assisted-user-interface (AUI). These fonnalisms are applied to the specification of ASSIST, a mechani- cal generator of assisted-user-interfaces which matches with command-line parser-generators technology. Finally, we show how the assist-paradigm can be implicitly combined with fonnally specified software modules, in the sense that each formal specification itself contains enough information for ASSIST to gen- erate the relevant parts of the AUI.