DESIGN OF REDUNDANT FORMAL SPECIFICATIONS BY LOGIC PROGRAMMING: MERGING FORMAL TEXT AND GOOD COMMENTS

Abstract

Among the various tasks involved in SE & KE, requirements engineering, specification, prototyping, and validation are regarded as crucial since they decide whether a software system fulfills the users’ expectations. Formal methods provide a rigorous framework to guaranteed. Logic Programming has been recently shown as a promising candidate support these tasks and some relevant features can be in that way captured and formally regarding these concerns. Nevertheless, formalism does need some explanation to let it be more readable and understandable. This paper focuses on a specification design method which mixes formal text (represented by a logic program) and comments (using either formal or informal assertions). By the design of a specification we refer to the intertwined tasks of describing the specification and improving it by the investigation of proofs. These proofs aim to verify the link between the specification and the comments, and are partly automated. Then we present our practical experience in the use of an interacti ve proof system. As an example, we show how this methodology is currently applied to the draft of standard Prolog.