A Look At Clp: Theory and Application

Constraint Logic Programming (CLP) is a relatively new programming paradigm. During its ten years of existence, the theory of CLP has been increasingly understood and the two diierent approaches, domain technology and incremental linear solving, have been implemented in various CLP systems. Meanwhile, the commercial attractivity of CLP has been growing. Since 1989 a couple of commercial CLP systems appeared on the software market and have been successfully used in many real life applications. The power of CLP stems from its ability to solve hard combinatorial problems such as planning, scheduling, resource allocation and many others. In this paper how CLP originated from two declarative paradigms (constraint solving and logic programming) is informally explained as well as the relationship between the existing diierent approaches in CLP is presented. The main part of the paper presents a real life scheduling application for the largest Slovak metallurgy company using the CLP system ECL i PS e , which we have been working on.