| Mathematical Structures in Computer Science (2005), 15:3:433-451 Cambridge University Press Copyright © 2005 Cambridge University Press doi:10.1017/S0960129505004743
Monads of coalgebras: rational terms and term graphs
AbstractThis paper introduces guarded and strongly guarded monads as a unified model of a variety of different term algebras covering fundamental examples such as initial algebras, final coalgebras, rational terms and term graphs. We develop a general method for obtaining finitary guarded monads that allows us to define and prove properties of the rational and term graph monads. Furthermore, our treatment of rational equations extends the traditional approach to allow right-hand sides of equations to be infinite terms, term graphs or other such coalgebraic structures. As an application, we use these generalised rational equations to sketch part of the correctness of the term graph implementation of functional programming languages. (Received July 11 2003)Footnotes1 Research supported by EPSRC grant GRM96230/01: Categorical Rewriting: Monads and Modularity |