src/main/java/ognl/OgnlContext.java
public Evaluation popEvaluation()
    {
        Evaluation result;

        result = _currentEvaluation;
        setCurrentEvaluation(result.getParent());
        if (_currentEvaluation == null) {
            setLastEvaluation(getKeepLastEvaluation() ? result : null);
            setRootEvaluation(null);
            setCurrentNode(null);
        }
        return result;
    }
public Evaluation popEvaluation()
    {
        Evaluation result;

        result = _currentEvaluation;
        setCurrentEvaluation(result.getParent());
        if (_currentEvaluation == null) {
            setLastEvaluation(getKeepLastEvaluation() ? result : null);
            setRootEvaluation(null);
            setCurrentNode(null);
        }
        return result;
    }
Pops the current Evaluation off of the top of the stack. This is done after a node has
completed its evaluation.