A Formal Approach to Domain-Oriented Software Design Environments

This paper describes a formal approach to domain-oriented software design environments, based on declarative domain theories, formal specifications, and deductive program synthesis. A declarative domain theory defines the semantics of a domain-oriented specification language and its relationship to implementation-level subroutines. Formal specification development and reuse is made accessible to users through an intuitive graphical interface that guides them in creating diagrams denoting formal specifications. Deductive program synthesis ensures that specifications are correctly implemented. This approach has been implemented in AMPHION, a generic KBSE system that targets scientific subroutine libraries. AMPHION has been applied to the domain of solar system kinematics. AMPHION enables space scientists to develop, modify, and reuse specifications an order of magnitude more rapidly than manual program development. Program synthesis is efficient and completely automatic. 1: Introduction This paper describes AMPHION 1 : an implemented Domain Oriented Design Environment (DODE). In contrast to previous approaches to DODEs [4], AMPHION is based on formal specifications and automated deductive synthesis for program development. Nonetheless, from a user's viewpoint, AMPHION is similar to previously published accounts of DODEs. The thesis of this paper is that the development , modification, and reuse of problem specifications — not programs— are the central activities around which a domain-oriented KBSE life cycle should revolve. This is in consonance with the original vision for the knowledge-based software assistant [5]. For the high-assurance soft-1. Amphion was Zeus's son who used his magic lyre to charm the stones around Thebes into position to form the city's walls. ware that characterizes NASA's needs, basing a DODE on formal specifications offers many advantages, and, as reported in this paper, is eminently feasible. Formal specifications provide an abstract and unambig-uous representation of a user's requirements. Formal methods ensure that a program is a correct implementation of a formal specification. AMPHION addresses several difficulties that have impeded formal frameworks being used in practice [8]. Users without a background in formal mathematics find that developing a formal problem specification is usually more difficult than developing code manually. In part, this is due to the need to formalize the domain concepts necessary to state a problem. Our approach to DODEs separates the activity of domain formalization from the activity of individual problem formalization. Users are also unaccustomed to the syntax and notation of mathematical logic. AMPHION incorporates techniques from visual programming and structured editing to guide users in creating domain-oriented diagrams that are translated …