DESIGN OF A COMPILER FOR LAZY PATTERN DRIVEN NARROWING

This paper describes the implementation of lazy pattern driven narrowing by extending an abstract machine for lazy rewriting to perform unification and backtracking. The abstract machine LANAM is based on implementation methods for functional and logic languages like LML and PROLOG. The approach leads to an efficient unification method for an equational theory and can also be used as a basis for efficient execution of functional logic programs. We give an abstract definition of the implemented algorithm, describe the architecture of the abstract machine and discuss performance and implementation issues.