General and Reusable Indexical Policies and Sketches

Recently, a simple but powerful language for expressing general policies and problem decompositions (sketches) have been introduced that is based on collections of rules defined on a set of Boolean and numerical features. In this work, we consider extensions of this basic language aimed at making policies and sketches more flexible and reusable. For this, three basic extensions are considered: 1) internal memory states, as in finite state controllers, 2) indexical features, whose values are a function of the state and a number of internal registers that can be loaded with objects, and 3) modules that wrap up policies and sketches and allow them to call each other by passing parameters. The expressive power of the resulting language for policies and sketches that are general and reusable is illustrated through examples.