Logic Programming

This chapter presents the family of logic programming languages in which computation is viewed as deduction in a logical formalism. We first present the foundation of logic programming with Horn clauses illustrated by the Prolog language. From this first concept are born numerous extensions; here we describe two of them in details: constraint logic programming which allows a more elegant treatment of domains other than finite terms and Answer Set Programming which gives a better treatment of negation and appears to be an effective implementation of non-monotonic reasoning.