Related specifications reuse

Building a program from an existing one-called design with program reuse-has a number of interesting payoffs but differs from classical program designs. This paper addresses the issue of program reuse in the context in which design is achieved by a transformational development. A design method for making easy the reuse is introduced. The idea is to highlight and exploit the link between two related specifications-the specification for which a program has to be developed and the specification of the program selected to be reused, in order to guide the program reuse. In practice, a set of "reuse schemes" is proposed and the program design is done by applying one or several of them to an initial specification. The use of such schemes allows to partially or completely systematize the program reuse by using first-order theorem proving. A reuse example illustrates the proposed design method.