R++ is an extension to C++ that supports rule-based programming. Thus, programs written in R++ have all the facilities of C++ plus a new programming construct: a rule. A rule is like an if-statement, but it is located apart from the procedural code and is triggered automatically upon changes to the data that it monitors. R++ was developed at AT&T Labs (just like C and C++). It facilitates the development of event-driven systems, debugging tools, database triggers, and Artificial Intelligence. You can read more about R++ and see samples of R++ vs. C++ code at www.research.att.com/sw/tools/r%2b%2b/.