Categorical Rewriting
Term Rewriting Systems (TRSs) are widely used throughout computer
science as they form an abstract model of computation. However, the
concrete syntactic nature of term rewriting often obscures the
underlying structure and a more abstract semantics is therefore needed.
Abstract Reduction Systems provide a relational
semantics for TRSs, but unfortunately these relations do not posses
enough structure to adequately model several key concepts. Hence the
relational model is used mainly as an organisational tool with the
difficult results proved directly at the syntactic level.
We believe that rewriting needs a semantics at an intermediate level
of abstraction between the syntax and the relational model. Originally
it was hoped that 2-categories would provide such a model but despite
some one-off results, 2-categorical models of TRSs have failed to make
a lasting impact. Our research focuses on applying the theory of
enriched monads to term rewriting with very promising results. These
monads have been used to give semantic proofs of some difficult
results in modular term rewriting. We are currently using monads to
tackle open problems in modular term rewriting for conditional TRSs
and unions which permit limited sharing.
Journal Papers
Research Papers
Author: Neil Ghani
Email: ng13@mcs.le.ac.uk
Tel: 44 (0)116 252 3807
Last Update: June 22 2000
The opinions expressed in this page are the authors' and not those of
the University.
Back to the homepage.