@Override
protected IScalarEvaluator createEvaluator(IHyracksTaskContext ctx, IScalarEvaluator[] args)
throws AlgebricksException {
final XSQNamePointable qnamep = (XSQNamePointable) XSQNamePointable.FACTORY.createPointable();
final SequencePointable seqp = (SequencePointable) SequencePointable.FACTORY.createPointable();
final UTF8StringPointable stringp = (UTF8StringPointable) UTF8StringPointable.FACTORY.createPointable();
final ArrayBackedValueStorage abvs = new ArrayBackedValueStorage();
final DataOutput dOut = abvs.getDataOutput();
return new AbstractTaggedValueArgumentScalarEvaluator(args) {
@Override
protected void evaluate(TaggedValuePointable[] args, IPointable result) throws SystemException {
TaggedValuePointable tvp1 = args[0];
// Only accept a QNames or empty sequence.
if (tvp1.getTag() == ValueTag.SEQUENCE_TAG) {
tvp1.getValue(seqp);
if (seqp.getEntryCount() == 0) {
XDMConstants.setEmptySequence(result);
return;
}
// Pass through.
}