Patterns for Refinement Automation

Abstract

Formal modelling is indispensable for engineering highly dependable systems. However, a wider acceptance of formal methods is hindered by their insufficient usability and scalability. In this paper, we aim at assisting developers in rigorous modelling and design by increasing automation of development steps. We introduce a notion of refinement patterns – generic representations of typical correctness-preserving model transformations. Our definition of a refinement pattern contains a description of syntactic model transformations, as well as the pattern applicability conditions and proof obligations for verifying correctness preservation. This work establishes a basis for building a tool that would support formal system development via pattern reuse and instantiation. We present a prototype of such a tool and some examples of refinement patterns for automated development in the Event B formalism.