LANGUAGE 69
The semantics of the problem domain is not the only source for DSM semantics.
Like all modeling languages targeting code generation, we must recognize the
semantics of the implementation side: howmodeling constructs are mapped to a given
solution domain. This mapping is made not to the problem domain but to another
language, here to a programming language. This is usually called operational
semantics. It is important to realize that the operational semantics cannot be the only
source for semantics. If it were, then the modeling language would actually map oneto-
one to the generated programming language. The abstraction would be the same
and the bene?¬?ts of code generation minimal.Aclassic example here is mapping a class
in a diagram to a class in a code. The developer who makes the class model is thus
already thinking with the concepts and semantics of code. If we want to increase
abstraction and improve productivity, the semantics of the problem domain matter
more than the semantics of the solution domain.
Concrete Syntax: Representation Pure abstract syntax and semantics are not
enough for a language de?¬?nition: models must be accessed through some visual
formalism.We need a concrete syntax in addition to the abstract one. Every modeling
language follows some representational form along with a notation.
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