Class KeySort

java.lang.Object

org.projog.core.predicate.AbstractSingleResultPredicate

org.projog.core.predicate.builtin.list.KeySort

All Implemented Interfaces:

KnowledgeBaseConsumer, PredicateFactory

public final class KeySort
extends AbstractSingleResultPredicate

keysort(X,Y) - sorts a list of key/value pairs.

Sorts the list X, containing key/value pairs, and attempts to unify the result with Y. Key/value pairs are compound terms with a functor of - and two arguments. The first argument is the key and the second argument is the value. It is the key of the key/value pairs that is used to sort the elements contained in X. (Note: duplicates are not removed.)

Field Summary

Fields

Modifier and Type	Field	Description
private static final Comparator<Term>	KEY_VALUE_PAIR_COMPARATOR

Constructor Summary

Constructors

Constructor	Description
KeySort()

Method Summary

Modifier and Type	Method	Description
private boolean	assertKeyValuePairs(List<Term> elements)
protected boolean	evaluate(Term original, Term result)

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

KEY_VALUE_PAIR_COMPARATOR

private static final Comparator<Term> KEY_VALUE_PAIR_COMPARATOR

Constructor Details

KeySort

public KeySort()

Method Details

evaluate

protected boolean evaluate(Term original,
 Term result)

Overrides:

evaluate in class AbstractSingleResultPredicate

assertKeyValuePairs

private boolean assertKeyValuePairs(List<Term> elements)