code: public Object evaluate(Object pContext,
                             VariableResolver pResolver,
                             Map functions,
                             String defaultPrefix,
                             Logger pLogger)
              throws ELException {
          Object value = mExpression.evaluate(pContext, pResolver, functions,
                  defaultPrefix, pLogger);
          if (mOperator != null) {
              value = mOperator.apply(value, pContext, pLogger);
          } else {
              for (int i = mOperators.size() - 1; i >= 0; i--) {
                  UnaryOperator operator = (UnaryOperator) mOperators.get(i);
                  value = operator.apply(value, pContext, pLogger);
              }
          }
          return value;
      }
docs: Evaluates to the literal value