if ((cardinality & Cardinality.ZERO) == 0)
if (Cardinality.checkCardinality(requiredCardinality, Cardinality.ZERO))
	public Sequence eval(Sequence contextSequence, Item contextItem) throws XPathException {        if (context.getProfiler().isEnabled()) {            context.getProfiler().start(this);                   context.getProfiler().message(this, Profiler.DEPENDENCIES, "DEPENDENCIES", Dependency.getDependenciesName(this.getDependencies()));            if (contextSequence != null)                context.getProfiler().message(this, Profiler.START_SEQUENCES, "CONTEXT SEQUENCE", contextSequence);            if (contextItem != null)                context.getProfiler().message(this, Profiler.START_SEQUENCES, "CONTEXT ITEM", contextItem.toSequence());        }                Sequence result;		Sequence seq = expression.eval(contextSequence, contextItem);		if(seq.isEmpty()) {			if ((cardinality & Cardinality.ZERO) == 0)                result = BooleanValue.FALSE;			else                result = BooleanValue.TRUE;		}        else {    		try {    			seq.itemAt(0).convertTo(requiredType);                result = BooleanValue.TRUE;            //TODO : improve by *not* using a costly exception ?    		} catch(XPathException e) {                result = BooleanValue.FALSE;    		}        }                if (context.getProfiler().isEnabled())                       context.getProfiler().end(this, "", result);                return result;        	}