Class Is

java.lang.Object

org.projog.core.predicate.AbstractSingleResultPredicate

org.projog.core.predicate.builtin.compare.Is

All Implemented Interfaces:

KnowledgeBaseConsumer, PredicateFactory, PreprocessablePredicateFactory

public final class Is
extends AbstractSingleResultPredicate
implements PreprocessablePredicateFactory

X is Y - evaluate arithmetic expression.

Firstly structure Y is evaluated as an arithmetic expression to give a number. Secondly an attempt is made to match the number to X. The goal succeeds or fails based on the match.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private static final class	Is.PreprocessedIs
private static final class	Is.Unify

Constructor Summary

Constructors

Constructor	Description
Is()

Method Summary

Modifier and Type	Method	Description
protected boolean	evaluate(Term arg1, Term arg2)
PredicateFactory	preprocess(Term arg)

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

getPredicate, isAlwaysCutOnBacktrack, isRetryable

Constructor Details

Is

public Is()

Method Details

evaluate

protected boolean evaluate(Term arg1,
 Term arg2)

Overrides:

evaluate in class AbstractSingleResultPredicate

preprocess

public PredicateFactory preprocess(Term arg)

Specified by:

preprocess in interface PreprocessablePredicateFactory