ConGolog, a concurrent programming language based on the situation calculus

As an alternative to planning, an approach to high-level agent control base d on concurrent program execution is considered. A formal definition in the situation calculus of such a programming language is presented and illustr ated with some examples. The language includes facilities for prioritizing the execution of concurrent processes, interrupting the execution when cert ain conditions become true, and dealing with exogenous actions. The languag e differs from other procedural formalisms for concurrency in that the init ial state can be incompletely specified and the primitive actions can be us er-defined by axioms in the situation calculus. Some mathematical propertie s of the language are proven, for instance, that the proposed semantics is equivalent to that given earlier for the portion of the language without co ncurrency. (C) 2000 Elsevier Science B.V. All rights reserved.