Advanced Search

Browse by Discipline

Scientific Societies

E-print Alerts

Add E-prints

E-print Network

  Advanced Search  

Needed Narrowing in Prolog Sergio Antoy

Summary: Needed Narrowing in Prolog
Sergio Antoy
Portland State University
TR 96-2
May 17, 1996
We describe the implementation of needed narrowing deployed in a compiler of a
functional-logic language and present a few related concepts and results. Our im-
plementation is obtained by translating rewrite rules into Prolog source code and
optionally applying a set of optimizations to this code. We benchmark the e ec-
tiveness of each individual optimization. We show that our implementation is more
e∆cient than all other previously proposed similar implementations. We measure
both execution times, as is customarily done, and memory allocation that turns out
to be a signi cant factor. We solve equations using a semi-strict equality relation
that generalizes classic strict equality with sometimes a smaller search space. We
give a new, more declarative and accessible formulation of a de nitional tree, a cru-
cial concept of our approach, and we present a simple algorithm to build de nitional
trees. We brie y explore a notion of simpli cation that is applicable to and some-
times bene cial for computations in inductively sequential systems, where classic
simpli cation is not applicable.


Source: Antoy, Sergio - Department of Computer Science, Portland State University


Collections: Computer Technologies and Information Sciences