Pragmatic reuse for DSML development

By bridging the semantic gap, domain-specific language (DSLs) serve an important role in the conquest to allow domain experts to model their systems themselves. In this publication we present a case study of the development of the Continuous REactive SysTems language (CREST), a DSL for hybrid systems modeling. The language focuses on the representation of continuous resource flows such as water, electricity, light or heat. Our methodology follows a very pragmatic approach, combining the syntactic and semantic principles of well-known modeling means such as hybrid automata, data-flow languages and architecture description languages into a coherent language. The borrowed aspects have been carefully combined and formalised in a well-defined operational semantics. The DSL provides two concrete syntaxes: CREST diagrams, a graphical language that is easily understandable and serves as a model basis, and crestdsl, an internal DSL implementation that supports rapid prototyping—both are geared towards usability and clarity. We present the DSL’s semantics, which thoroughly connect the various language concerns into an executable formalism that enables sound simulation and formal verification in crestdsl, and discuss the lessons learned throughout the project.