Formalizing the semantics of ASCEND

ASCEND is a declarative and strongly-typed executable equational modeling language. Originally developed to support engineering design, it has since been applied in various other domains. ASCEND is distinctive in its use of strong typing for integrating data and algebraic modeling, and in providing model structuring operators which facilitate model reuse. In this paper, we develop a declarative semantics for the type system in ASCEND. Our purpose is to clarify the meaning of ASCEND constructs (thereby also explaining the operational semantics embodied in the ASCEND compiler), and to enable a systematic and principled investigation of modifications to the language. Our approach is based on formal logic, in particular, the embedded languages technique.<>