A Comprehensive Setting for Matching and Unification over Iterative Terms

Authors:
B. Intrigila;P. Inverardi;M. Venturini Zilli
Affiliations:
(Correspd.) Dipartimento di Matematica pura ed applicata, University of L'Aquila, L'Aquila, Italy. intrigila@univaq.it;(Correspd.) Dipartimento di Matematica pura ed applicata, University of L'Aquila, L'Aquila, Italy. inverard@univaq.it;(Correspd.) Dipartimento di Scienze dell'informazione, University of Rome ‘La Sapienza’ Rome, Italy. zilli@dsi.uniroma1.it
Venue:
Fundamenta Informaticae
Year:
1999

Citing 11
Cited 0

Logic programming with recurrence domains

Proceedings of the 18th international colloquium on Automata, languages and programming
Generalizations of unification

Journal of Symbolic Computation
Recurrence domains: their unification and application to logic programming

Information and Computation
A remark on infinite matching vs. infinite unification

Journal of Symbolic Computation
Unification of infinite sets of terms schematized by primal grammars

Theoretical Computer Science
Yet Another Real-Time Specification for the Steam Boiler: Local Clocks to Statically Measure Systems Performance

FASE '99 Proceedings of the Second Internationsl Conference on Fundamental Approaches to Software Engineering
The Unification of Infinite Sets of Terms and Its Applications

LPAR '92 Proceedings of the International Conference on Logic Programming and Automated Reasoning
Rational Rewriting

MFCS '94 Proceedings of the 19th International Symposium on Mathematical Foundations of Computer Science 1994
Static Analysis of Real-Time Component-Based Systems Configurations

COORDINATION '99 Proceedings of the Third International Conference on Coordination Languages and Models
On Finite Representations of Infinite Sequences of Terms

Proceedings of the 2nd International CTRS Workshop on Conditional and Typed Rewriting Systems
EQUATIONAL TERM GRAPH REWRITING

Fundamenta Informaticae

Quantified Score

Hi-index	0.00

Visualization

Abstract

Terms finitely representing infinite sequences of finite first-order terms have received attention by several authors. In this paper, we consider the class of recurrent terms proposed by H. Chen and J. Hsiang, and we extend it to allow infinite terms. This extension helps in clarifying the relationships between matching and unification over the class of terms we consider, that we call iterative terms. In fact, it holds that if a term s matches a term t by a substitution &Ggr;, then the limit of iterations of the matching &Ggr;, if it exists, is a most general unifier of s and t. A crucial feature of iterative terms is the notion of maximally-folded normal form that allows for a comprehensive treatment of both finite and infinite iterative terms. In this setting, infinite terms can be simply characterized as limits of sequences of finite terms. For finite terms we positively settle an open problem of H. Chen and J. Hsiang on the number of most general unifiers for a pair of terms.