A DENOTATIONAL APPROACH TO LANGUAGE SPECIFICATION: A CAUSAL BLOCK DIAGRAM CASE STUDY

Abstract: In the design of embedded control systems, a variety of languages are used by different teams and in different development phases. Part of this variety comes from the use of domain-specific modeling languages that are tailored to the mental concepts of the user. This puts forward the need for efficient, systematic, and structured design of the modeling languages themselves. In particular, a precise and preferably executable specification of the language should be provided, although not all domain-specific language may be specified in this manner. A denotational semantics can provide such a specification. This paper presents a denotational semantics for a language BdAppLang. BdAppLang can be viewed as an abstract syntax for a simple subset of the domain-specific language of causal block diagrams, which are predominantly used in the system-level phase of control system design. The semantics are given in Haskell, and thus are executable while still conforming to the tradition of giving denotational semantics in a language derived from the lambda calculus