%T User\-Defined Data Types and Operators in occam %A David C. Wood, James Moores %E Barry M. Cook %B Proceedings of WoTUG\-22: Architectures, Languages and Techniques for Concurrent Systems %X This paper describes the addition of user\-defined monadic and dyadic operators to occam, together with some libraries that demonstrate their use. It also discusses some techniques used in their implementation in KRoC for a variety of target machines.