An Algebraic Specification of an Interface Definition Language

Karen Stephenson

(University of Wales Swansea)

We construct a simple language for defining software interfaces. We then produce an algebraic specification of this Interface Definition Language, focusing on how we can filter the strings of the language so that we only allow syntactically valid interfaces to be defined. One aspect that determines the validity of an interface is whether its architecture is well-formed or not, for example: "Is an interface constructed from another that is absent from the system?" "Are there any cyclic dependencies between interfaces?" We frame such questions algebraically, and specify how we can extract the architecture of a system from its interfaces: the architecture of a well-formed system is a term that represents the tree of dependencies between interfaces. Finally, we describe the transformation of an interface into a signature, as the first step in providing a semantics for an interface.
Tuesday 16th March 1999, 15:00
Seminar Room 322
Department of Computer Science