/**
* Returns an array of all {@link Term}s that make up the conjunction represented by the specified
* {@link Term}.
*
* <p>If the specified {@link Term} does not represent a conjunction then it will be used as the
* only element in the returned array.
*/
public static Term[] toArrayOfConjunctions(Term t) {
List<Term> l = new ArrayList<>();
while (isConjunction(t)) {
l.add(0, t.getArgs()[1]);
t = t.getArgs()[0];
}
l.add(0, t);
return l.toArray(new Term[l.size()]);
}
private void assertMultipleResultsTailRecursive(String input) {
Term parsedSentence = TestUtils.parseSentence(input);
assertFalse(isSingleResultTailRecursive(copyClauses(), parsedSentence.getArgs()));
}
/** Returns a {@link Predicate} instance for the specified {@link Term}. */
public static Predicate getPredicate(KnowledgeBase kb, Term t) {
return kb.getPredicateFactory(t).getPredicate(t.getArgs());
}
/**
* Returns {@code true} if the specified {@link Term} represent a conjunction, else {@code false}.
*
* <p>A {@link Term} is judged to represent a conjunction if is a structure with a functor of
* {@link #CONJUNCTION_PREDICATE_NAME} and exactly two arguments.
*/
public static boolean isConjunction(Term t) {
// is relying on assumption that conjunctions are only, and always, represented by a comma
return t.getType() == TermType.STRUCTURE
&& CONJUNCTION_PREDICATE_NAME.equals(t.getName())
&& t.getArgs().length == 2;
}