From ease in programming to easy maintenance: extending DSL usability with montages

Abstract

Montages is a formalism for giving executable specifications of programming languages. In contrast to related formalisms, it is state-based, and specifications can be given in an imperative or object-oriented style with which most programmers are comfortable. Hence, in the context of Domain Specific Languages (DSLs), it provides a framework in which domain engineers can themselves extend and maintain their language. It also uses visual notations, resulting in concise, intelligible specifications. Using the associated tool support Gem-Mex, such specifications can be used to automatically generate a programming environment with animation facilities. In this paper, we give an overview of the formalism and the tool support, focusing on its advantages in DSL maintenance and implementation. Towards this we also present a case study using a language called HYSDEL, developed by control engineers for specifying hybrid systems. A full implementation of this language is available and is currently being maintained by the Automatic Control Laboratory of ETH Zurich.