Class Dif

java.lang.Object

org.projog.core.predicate.AbstractSingleResultPredicate

org.projog.core.predicate.builtin.reif.Dif

All Implemented Interfaces:

KnowledgeBaseConsumer, PredicateFactory

public final class Dif
extends AbstractSingleResultPredicate

dif(X,Y) - enforces restriction that the two given terms are never equal.

If X and Y cannot unify then the goal succeeds. If X and Y are equal then the goal fails. If X and Y could unify then a restriction is added to prevent X and Y from unifying in the future.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private static final class	Dif.DifVariableAttribute
private static final class	Dif.MyMap

Field Summary

Fields

Modifier and Type	Field	Description
private static final Dif.DifVariableAttribute	ATTRIBUTE_KEY

Constructor Summary

Constructors

Constructor	Description
Dif()

Method Summary

Modifier and Type	Method	Description
private static void	appendAttribute(Variable v, Term attributeElement)
private Term	createTerm(List<? extends Term> args)
boolean	evaluate(Term arg1, Term arg2)

Methods inherited from class AbstractSingleResultPredicate

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

Methods inherited from class Object

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

Methods inherited from interface PredicateFactory

isAlwaysCutOnBacktrack

Field Details

ATTRIBUTE_KEY

private static final Dif.DifVariableAttribute ATTRIBUTE_KEY

Constructor Details

Dif

public Dif()

Method Details

evaluate

public boolean evaluate(Term arg1,
 Term arg2)

Overrides:

evaluate in class AbstractSingleResultPredicate

createTerm

private Term createTerm(List<? extends Term> args)

appendAttribute

private static void appendAttribute(Variable v,
 Term attributeElement)