Montages: Unified Static and Dynamic Semantics of Programming Languages

We unify static and dynamic semantics through the use of Montages, a version of Evolving Algebras specially tailored for programming languages. Montages combines graphical and textual elements to yield specifications similar in structure, length, and complexity to those in common language manuals, but with a formal semantics. We aim at a formal instrument which can be equally good understood by language designers, compiler constructors, and programmers. T I CT := CT.NT endif if CT.Condition.Value then Apply(CT)(CT.Left.Value, CT.Right.Value) else CT.Value := if RelOp(CT) then endif endif CT := CT.NT CT := CT.TrueTask Right Left S2-Expr S1-Expr NT NT S-RelOp WhileStment ::= WHILE Expr RelOp Expr DO StmentSeq END NT S-DO NT if DO(CT) then Condition TrueTask S-StmentSeq condition CHECK BOOL EXPR 1 Introduction Our work introduces Montages as a method for defining programming language semantics using Evolving Algebras. EAs have been proposed by Y. Gurevich as a dynamic generaliza..