Package org.projog.core.predicate.builtin.construct

Class Functor

java.lang.Object

org.projog.core.predicate.AbstractSingleResultPredicate

org.projog.core.predicate.builtin.construct.Functor

All Implemented Interfaces:

KnowledgeBaseConsumer, PredicateFactory

public final class Functor
extends AbstractSingleResultPredicate

functor(T,F,N)

Predicate functor(T,F,N) means "T is a structure with name (functor) F and N number of arguments".

Constructor Summary

Constructors

Constructor	Description
Functor()

Method Summary

Modifier and Type	Method	Description
private Term	createTerm(Term functor, Term arity)	Creates a term using the given functor (name) and arity (number of arguments).
protected boolean	evaluate(Term term, Term functor, Term arity)

Methods inherited from class org.projog.core.predicate.AbstractSingleResultPredicate

evaluate, evaluate, evaluate, evaluate, evaluate, getArithmeticOperators, getFileHandles, getKnowledgeBase, getOperands, getPredicate, getPredicates, getProjogListeners, getSpyPoints, getTermFormatter, init, isRetryable, setKnowledgeBase

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.projog.core.predicate.PredicateFactory

isAlwaysCutOnBacktrack

Constructor Detail

Functor

public Functor()

Method Detail

evaluate

protected boolean evaluate(Term term,
                           Term functor,
                           Term arity)

Overrides:

evaluate in class AbstractSingleResultPredicate

createTerm

private Term createTerm(Term functor,
                        Term arity)

Creates a term using the given functor (name) and arity (number of arguments).

Parameters:

functor - an atom representing the name of the term to create

arity - a numeric representing the number of arguments of the term to create

Returns:

if arity is 0 then an atom will be returned, else a structure will be created.