[Prev][Next][Index][Thread]
Optimal Derivation in Term Rewriting Systems, 1/29, 10:45am
Date: Wed, 16 Jan 91 10:31:56 EST
SEMINAR
Date: Tuesday, January 29, 1991
Time: Refreshments at 10:45 a.m.
Place: Second Floor Lounge
Optimal Derivation in Term Rewriting Systems
Without Critical Pairs
Luc Maranget
INRIA
Abstract
This work introduces a new notion of labeled Term
Rewriting Systems (labeled TRS). This notion expresses sharing
in TRS. A new notion of conditional TRS is also introduced.
Conditional TRS allows us to extend the properties of TRS
without critical pairs to a class of Systems wider than the
usual one. In this extended notion of systems without critical
pairs, optimal derivations are characterized. Furthermore, for
any normalizable term, it is possible to compute an optimal
normalizing derivation.
These results are applied to two systems describing weak
lambda-calculi. The call-by-name-with-sharing or lazy strategy
is shown to be optimal in these systems.
Host: Professor Arvind