@Override
public Value value(final QueryContext ctx) throws QueryException {
final int o = (int) ctx.resources.output.size();
final Updates updates = ctx.resources.updates();
final ContextModifier tmp = updates.mod;
final TransformModifier pu = new TransformModifier();
updates.mod = pu;
try {
for (final Let fo : copies) {
final Iter ir = ctx.iter(fo.expr);
Item i = ir.next();
if (!(i instanceof ANode) || ir.next() != null) throw UPCOPYMULT.get(fo.info, fo.var.name);
// copy node to main memory data instance
i = ((ANode) i).dbCopy(ctx.context.options);
// add resulting node to variable
ctx.set(fo.var, i, info);
pu.addData(i.data());
}
final Value v = ctx.value(expr[0]);
if (!v.isEmpty()) throw BASEX_MOD.get(info);
updates.prepare();
updates.apply();
return ctx.value(expr[1]);
} finally {
ctx.resources.output.size(o);
updates.mod = tmp;
}
}
/**
* Checks if the predicates are successful for the specified item.
*
* @param it item to be checked
* @param qc query context
* @return result of check
* @throws QueryException query exception
*/
protected final boolean preds(final Item it, final QueryContext qc) throws QueryException {
if (preds.length == 0) return true;
// set context value and position
final Value cv = qc.value;
try {
if (qc.scoring) {
double s = 0;
for (final Expr p : preds) {
qc.value = it;
final Item i = p.test(qc, info);
if (i == null) return false;
s += i.score();
}
it.score(Scoring.avg(s, preds.length));
} else {
for (final Expr p : preds) {
qc.value = it;
if (p.test(qc, info) == null) return false;
}
}
return true;
} finally {
qc.value = cv;
}
}
/**
* Checks two keys for equality.
*
* @param its1 first keys
* @param its2 second keys
* @param coll collations
* @return {@code true} if the compare as equal, {@code false} otherwise
* @throws QueryException query exception
*/
private boolean eq(final Item[] its1, final Item[] its2, final Collation[] coll)
throws QueryException {
final int il = its1.length;
for (int i = 0; i < il; i++) {
final Item it1 = its1[i], it2 = its2[i];
if (it1 == null ^ it2 == null || it1 != null && !it1.equiv(it2, coll[i], info)) return false;
}
return true;
}
/**
* Performs the assert-equals function.
*
* @param ctx query context
* @return resulting value
* @throws QueryException query exception
*/
private Item assertEquals(final QueryContext ctx) throws QueryException {
final byte[] str = expr.length < 3 ? null : checkStr(expr[2], ctx);
final Iter iter1 = ctx.iter(expr[0]), iter2 = ctx.iter(expr[1]);
final Compare comp = new Compare(info);
Item it1, it2;
int c = 1;
while (true) {
it1 = iter1.next();
it2 = iter2.next();
final boolean empty1 = it1 == null, empty2 = it2 == null;
if (empty1 && empty2) return null;
if (empty1 || empty2 || !comp.deep(it1.iter(), it2.iter())) break;
c++;
}
if (str != null) throw UNIT_MESSAGE.get(info, str);
throw new UnitException(info, UNIT_ASSERT_EQUALS, it1, it2, c);
}
@Override
public Item item(final QueryContext qc, final InputInfo ii) throws QueryException {
// compute scoring
if (qc.scoring) {
double s = 0;
boolean f = false;
for (final Expr expr : exprs) {
final Item it = expr.ebv(qc, info);
f |= it.bool(ii);
s += it.score();
}
return Bln.get(f, Scoring.avg(s, exprs.length));
}
// standard evaluation
for (final Expr expr : exprs) {
if (expr.ebv(qc, info).bool(ii)) return Bln.TRUE;
}
return Bln.FALSE;
}