================================================================ Logtalk - Open source object-oriented logic programming language Release 2.30.7 Copyright (c) 1998-2007 Paulo Moura. All Rights Reserved. ================================================================ To load this example and for sample queries, please see the SCRIPT file. This example shows the use of meta-predicates in Logtalk. Meta-predicates are predicates whose head contains arguments that will be called as goals in the body of the predicate definition. This example defines two objects: sort(_) this is a parametric object containing a method that implements the quicksort sorting algorithm; the parameter is interpreted as the type of the elements being sorted tracer this object implements a meta-predicate that is used by sort(_) to trace the sorting algorithm steps