func (e *ConditionOperand) evalNode(r Record, tableAlias string) (*Value, error) {
	opVal, opErr := e.Operand.evalNode(r, tableAlias)
	if opErr != nil || e.ConditionRHS == nil {
		return opVal, opErr
	}

	// Need to evaluate the ConditionRHS
	switch {
	case e.ConditionRHS.Compare != nil:
		cmpRight, cmpRErr := e.ConditionRHS.Compare.Operand.evalNode(r, tableAlias)
		if cmpRErr != nil {
			return nil, cmpRErr
		}

        assertNull(ee.evaluate("${rootDirectory}"));
    }

    @Test
    void testRootDirectoryWithNull() throws Exception {
        ExpressionEvaluator ee = createExpressionEvaluator(createDefaultProject(), new Properties());
        Exception e = assertThrows(Exception.class, () -> ee.evaluate("${session.rootDirectory}"));

        TestBean bean2 = new TestBean();
        PlexusConfiguration config = new XmlPlexusConfiguration("test");
        config.setValue("value1");

        when(evaluator.evaluate("value1")).thenReturn("value1");
        when(evaluator.evaluate("value2")).thenReturn("value2");

        java.lang.reflect.Field field = TestBean.class.getDeclaredField("directField");

        // First access

        when(evaluator.evaluate(anyString())).thenReturn("testValue");
        for (int i = 0; i < 10; i++) {
            when(evaluator.evaluate(Integer.toString(i))).thenReturn(i);
        }
        when(evaluator.evaluate("123")).thenReturn(123);
        when(evaluator.evaluate("456")).thenReturn(456);
        when(evaluator.evaluate("true")).thenReturn(true);

        XmlNode toXml(PlexusConfiguration config, ExpressionEvaluator evaluator) throws ExpressionEvaluationException {
            List<XmlNode> children = new ArrayList<>();
            for (PlexusConfiguration c : config.getChildren()) {
                children.add(toXml(c, evaluator));
            }
            String name = config.getName();
            Object value = evaluator.evaluate(config.getValue());

	return &Evaluator{
		policy: policy,
	}
}

// WithLockRetention - sets the lock retention configuration for the evaluator
func (e *Evaluator) WithLockRetention(lr *objlock.Retention) *Evaluator {
	e.lockRetention = lr
	return e
}

// WithReplicationConfig - sets the replication configuration for the evaluator
func (e *Evaluator) WithReplicationConfig(rcfg *replication.Config) *Evaluator {
	e.replCfg = rcfg
	return e
}

   * Returns a predicate that evaluates to {@code true} if any one of its components evaluates to
   * {@code true}. The components are evaluated in order, and evaluation will be "short-circuited"
   * as soon as a true predicate is found. It defensively copies the iterable passed in, so future
   * changes to it won't alter the behavior of this predicate. If {@code components} is empty, the
   * returned predicate will always evaluate to {@code false}.
   *

			if len(testCase.withJSON) > 0 {
				in = testCase.withJSON
			}
			if err = s3Select.Open(newStringRSC(in)); err != nil {
				t.Fatal(err)
			}

			w := &testResponseWriter{}
			s3Select.Evaluate(w)
			s3Select.Close()
			resp := http.Response{
				StatusCode:    http.StatusOK,
				Body:          io.NopCloser(bytes.NewReader(w.response)),
				ContentLength: int64(len(w.response)),
			}

/// tip

**GraphQL** solves some very specific use cases.

It has **advantages** and **disadvantages** when compared to common **web APIs**.

Make sure you evaluate if the **benefits** for your use case compensate the **drawbacks**. 🤓

///

## GraphQL Libraries { #graphql-libraries }

    public Object getValue(String expression) {
        if (expression == null || expression.trim().isEmpty()) {
            return null;
        }

        try {
            return ReflectionValueExtractor.evaluate(expression, root, false);
        } catch (Exception e) {
            addFeedback("Failed to extract \'" + expression + "\' from: " + root, e);
        }

        return null;
    }