Chapter 6 - Casl for CafeOBJ Users

Abstract

This chapter focuses on common algebraic specification language (CASL) and explaining how its language constructs relate to those of CafeOBJ. CASL is an expressive language for the algebraic specification of software requirements, design, and architecture. It has been developed by an open collaborative effort called Common Framework Initiative for algebraic specification and development (CoFI). CASL combines the best features of many previous mainstream algebraic specification languages. CafeOBJ, on the other hand, is a new generation algebraic specification and programming language. As a direct successor of OBJ, it inherits all its features such as flexible mix-fix syntax, powerful typing system, with sub-types, and sophisticated module composition system featuring various kinds of imports, parameterized modules, views for instantiating the parameters and module expressions, but it also implements new paradigms such as rewriting logic and hidden algebra, as well as their combination. This chapter presents CASL for users of the CafeOBJ framework, giving relationships between the two languages. It also discusses about those constructs of CafeOBJ that have direct counterparts in CASL, and those that do not. It motivates various CASL constructs that are not provided by CafeOBJ. Finally, this chapter gives a concise overview of CASL, and illustrates how some CafeOBJ specifications may be expressed in CASL.