Summary: 9th Int'l Symp. on Prog. Lang., Implementations, Logics, and Programs (PLILP'97)
Southampton, UK, Sept. 1997, Springer LNCS Vol. 1292, pages 1-15.
Narrowing the Narrowing Space ?
Sergio Antoy 1 and Zena M. Ariola 2
1 Portland State University
2 University of Oregon
Abstract. We introduce a framework for managing as a whole the space
of a narrowing computation. The aim of our framework is to nd a
nite representation of an innite narrowing space. This, in turn, al-
lows us to replace an innite enumeration of computed answers with an
equivalent nite representation. We provide a semidecidable condition for
this result. Our framework is intended to be used by implementations
of functional logic programming languages. Our approach borrows from
the memoization technique used in the implementation of functional lan-
guages. Since narrowing adds non-determinism and uniers to functional
evaluation, we develop a new approach based on graphs to memoize the
outcome of a goal.
Keywords Functional logic programming, Narrowing, Narrowing space, Com-
puted expression, Regular computed expression, Finite representation.