public Value eval(String expr) throws Debugger.EvaluationException {
    assert isValid();

    Saxon9TraceListener.MUTED = true;
    try {
      return createValue(new ExpressionFacade(myElement));
    } catch (AssertionError | Exception e) {
      debug(e);
      throw new Debugger.EvaluationException(e.getMessage() != null ? e.getMessage() : e.toString());
    }
    finally {
      Saxon9TraceListener.MUTED = false;
    }
  }
public Value eval(String expr)