Oz - A Programming Language for Multi-Agent Systems

Oz is an experimental higher-order concurrent constraint programming system under development at DFKI. It combines ideas from logic and concurrent programming in a simple yet expressive language. From logic programming Oz inherits logic variables and logic data structures, which provide for a programming style where partial information about the values of variables is imposed concurrently and incremen-tally. A novel feature of Oz is that it accommodates higher-order programming without sacri-cing that denotation and equality of variables are captured by rst-order logic. Another new feature of Oz is constraint communication, a new form of asynchronous communication exploiting logic variables. Constraint communication avoids the problems of stream communication , the conventional communication mechanism employed in concurrent logic programming. Constraint communication can be seen as providing a minimal form of state fully compatible with logic data structures. Based on constraint communication and higher-order programming, Oz readily supports a variety of object-oriented programming styles including multiple inheritance.