Structural Operational Semantics for AKL

The Andorra Kernel Language (AKL) is a concurrent constraint programming language. It can be seen as a general combination of logic programming languages such as Prolog, GHC, and Parlog, the first of which provides don't know nondeterminism, and the last two of which are concurrent logic programming languages. The constraint system is an independent parameter of the language description. In this paper, we revisit the description of Janson and Haridi [10], adding the formal machinery which is necessary in order to completely formalize the control of the computation model. To this we add a formal description of the transformational semantics of AKL. The semantics is a set of or-trees which also captures infinite computations. 1 Introduction The Andorra Kernel Language (AKL) is a general combination of search-oriented don't know nondeterministic logic programming languages, such as Prolog, and process-oriented concurrent logic programming languages, such as GHC, Parlog, and others [18, 6..