This paper describes the design, implementation, and applications of the constraint logic language cc(FD). cc(FD) is a declarative nondeterministic constraint logic language over finite domains based on the cc framework [33], an extension of the CLP scheme [21]. Its constraint solver includes (non-linear) arithmetic constraints over natural numbers which are approximated using domain and interval consistency. The main novelty of cc(FD) is the inclusion of a number of general-purpose combinators, in particular cardinality, constructive disjunction, and blocking implication, in conjunction with new constraint operations such as constraint entailment and generalization. These combinators signi cantly improve the operational expressiveness, extensibility, and flexibility of CLP languages and allow issues such as the definition of non-primitive constraints and disjunctions to be tackled at the language level. The implementation of cc(FD) (about 40,000 lines of C) includes a WAM-based engine [44], optimal arc-consistency algorithms based on AC-5 [40], and incremental implementation of the combinators. Results on numerous problems, including scheduling, resource allocation, sequencing, packing, and hamiltonian paths are reported and indicate that cc(FD) comes close to procedural languages on a number of combinatorial problems. In addition, a small cc(FD) program was able to nd the optimal solution and prove optimality to a famous 10/10 disjunctive scheduling problem [29], which was left open for more than 20 years and nally solved in 1986.

Type classes are an elegant extension to traditional, Hindley-Milner based typing systems.

. Constraint solving has been successfully employed in diverse areas such as Operation Research, Planning, Logic Programming, and Automated Deduction. This has led to the development of a number of specialised approaches as well as to the adoption of different integration schemes and methodologies. In this paper we introduce an approach to incorporate constraint solving in term rewriting and we compare it with the Constraint Logic Programming scheme. We compare the two approaches both at the theoretical and at the implementational level and discuss potentials for cross-fertilisation. 1 Introduction Constraint solving aims at the development of efficient procedures tailored to restricted domains as well as to the integration of such procedures into general purpose reasoners. Constraint solving has been successfully employed in diverse areas such as Operation Research, Planning, Logic Programming, and Automated Deduction. This has led to the development of a number of specialised approa...

Abstract: A qualitative representational model and the corresponding reasoning process for integrating time and topological information is developed in this paper. In the calculus presented, topological information in function of the point of the time in which it is true is represented as an instance of the Constraint Satisfaction Problem. The resulting method can be applied to qualitative navigation of autonomous agents. The model presented in this paper will help us during the path planning task by describing the sequence of topological situations that the agent should find during its way to the target objective. A preliminary result of that application has been obtained by using qualitative representation of such spatial aspects for the autonomous simulated navigation of a Nomad-200 robot, on a structured environment of an easy corridor in a building.

This article presents an in-depth study of the close connection between Haskell type classes and C++ template/traits mechanism- two different facilties for implementing generic programming concepts. Haskell type classes and various extensions can be closely mimicked by C++ templates/traits and related mechanisms. We highlight the subtleties related to type-based computations and the limitations induced by language design on the program behaviour by a number of examples. 1

In this paper we present a qualitative representational model and the corresponding reasoning process for integrating qualitatively time and topological information. In the calculus presented topological information in function of the point of the time in which it is true is represented as an instance of the Constraint Satisfaction Problem. That representation together with the implementation of the reasoning process by means of Constraint Logic programming extended with Constraint Handling Rules allow us the integration of both aspects (time and topology) with other spatial aspects such as orientation, distances and cardinal directions, The resulting method can be applied to qualitative navigation of autonomous agents. The model presented in this paper will help during the path-planning task by describing the sequence of topological situations that the agent should find during its way to the target objective.

This is the final technical deliverable of the APPLAUSE project. It provides a summary of the APPLAUSE technology and its implementation in ElipSys and ECL i PS e . It then includes a tutorial on how to use constraints and parallelism in ECL i PS e . The main part of the book contains descriptions of the APPLAUSE applications summarizing the experience gathered in the course of the project. The book is targeted at potential users of parallel constraint logic programming (CLP) and ECL i PS e . It aims to encourage them to exploit the potential of parallel CLP by presenting the APPLAUSE exemplars. European Computer-Industry Research Centre GmbH Arabellastr. 17, D-81925 Munchen Germany Contents Chapter 1. The APPLAUSE Project by Alexander Herold 6 1 The APPLAUSE Framework : : : : : : : : : : : : : : : : : : : : : : : : : : 7 2 The APPLAUSE Technology : : : : : : : : : : : : : : : : : : : : : : : : : : 9 3 The APPLAUSE Systems : : : : : : : : : : : : : : : : : : : : : : : :...

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