String assertion = optElement.getAttributeValue(assertAtt);
if (assertion != null) {
TinyBuilder builder = new TinyBuilder();
builder.setPipelineConfiguration(saConfig.makePipelineConfiguration());
ExpressionPresenter presenter = new ExpressionPresenter(saConfig, builder);
xqe.explain(presenter);
presenter.close();
NodeInfo expressionTree = builder.getCurrentRoot();
XPathEvaluator xpe = new XPathEvaluator(saConfig);
XPathExpression exp = xpe.createExpression(assertion);
try {