}

        if (basedir == null) {
            basedir = session.getTopDirectory();
        }

        if (basedir == null) {
            basedir = Paths.get(System.getProperty("user.dir"));
        }

        this.basedir = basedir;
    }

    @Override
    public Object evaluate(String expr) throws ExpressionEvaluationException {
        return evaluate(expr, null);
    }