eval method

@override Object eval(FormInstance instance, EvaluationContext ec)

Evaluates the expression.

Implementation

@override
Object eval(FormInstance instance, EvaluationContext ec) {
  try {
    return expr.eval(instance, ec);
  } on XPathException catch (e) {
    e.source =
        'Condition expression for '
        '${context.toString(includePredicates: true)}';
    rethrow;
  }
}