Document Type

Technical Report

Publication Date

Winter 12-1-1972


The formal definition of the syntax and semantics of A Parameter Passing Language (APPL) is presented. APPL is a simple, nested structure language which permits the communication of parameters between a main program and a subroutine using call by reference, call by value, or call by name. The methodology and techniques of the Vienna Definition Language are used in the formalization of APPL. The syntactic definition of APPL consists of phrase structure grammars for concrete and abstract representations of valid APPL programs. The semantic definition of APPL is in terms of an abstract machine which interprets abstract programs. The machine specification consists of the machine state components and a trasition function that maps states into successor states. The semantics of various parameter passing mechanisms is thus formalized as the sequenceof machine states assumed by the abstract machine during the interpretation of abstract programs.