Experiments in reactive constraint logic programming1This paper is the complete version of a previous paper published in [14].1

AbstractIn this paper we study a reactive extension of constraint logic programming (CLP). Our primary concerns are search problems in a dynamic environment, where interactions with the user (e.g. in interactive multi-criteria optimization problems) or interactions with the physical world (e.g. in time evolving problems) can be modeled and solved efficiently. Our approach is based on a complete set of query manipulation commands for both the addition and the deletion of constraints and atoms in the query. We define a fully incremental model of execution which, contrary to other proposals, retains as much information as possible from the last derivation preceding a query manipulation command. The completeness of the execution model is proved in a simple framework of transformations for CSLD derivations, and of constraint propagation seen as chaotic iteration of closure operators. A prototype implementation of this execution model is described and evaluated on two applications

An Intelligent Backtracking Schema in a Logic Programming Environment

We present a new method to represent variable bindings in the Warren Abstract Machine (WAM), so that the ages of variable bindings can be easily found using this new representation in our intelligent backtracking schema. The age of a variable bound to a non-variable term is the youngest choice point such that backtracking to that choice point can make that variable an unbound variable again. The procedure backtracking point is the choice point of the procedure currently being executed or the choice point of its first ancestor having a choice point. Variable ages and procedure backtracking points are used in the process of figuring out backtracking points in our intelligent backtracking schema. Our intelligent backtracking schema performs much better than the results of other intelligent backtracking methods in the literature for deterministic programs, and its performance for non-deterministic programs are comparable with their results

Contribution à l'intégration de C++ et de Prolog à travers la machine abstraite de Warren le système cop-compilé

Ce mémoire présente le système COP-Compilé. C'est un système permettant l'intégration de la programmation procédurale en C++ et de la programmation logique en Prolog. Le noyau de ce système est un compilateur de Prolog basé sur la machine abstraite de Warren (WAM). Cette machine qui définit une organisation de la mémoire, un ensemble de registres et un jeu d'instructions adaptés à Prolog, est actuellement la référence par excellence dans le domaine d'implantation de compilateurs Prolog. Ce projet de recherche s'insère dans le cadre d'une série de travaux qui visent à rapprocher la programmation procédurale et la programmation logique. L'objectif principal de ce projet est d'augmenter la performance d'une première version d'un compilateur réalisant l'intégration des deux styles de programmation où le code Prolog était interprété. Le système COP-Compilé a réussi à augmenter la performance du système COP original et à améliorer ses possibilités en diminuant son temps d'exécution et en étendant les programmes Prolog qu'il est capable de reconnaître