Pattern Calculus

The pattern calculus is a new foundation for computation, in which the expressive power of functions and of data structures are combined within pattern-matching functions. The best existing foundations focus on either functions, as in the lambda-calculus, or on data structures, as in Turing machines, or on compromises involving both, as in object-orientation. By contrast, a small typed pattern calculus is able to support all the main programming styles, including functional, imperative, object-oriented and query-based styles, and there is evidence that it can support a language for Web services, able to exploit data structures about which almost nothing is known.