已经加好了，但是里面有个定义，像这样，有谁帮我看下啥意思。
OperatorClasses: array [TdxOperatorType] of TdxAbstractOperatorClass =
(TdxNullOperator, TdxEqualOperator, TdxGreaterOperator, TdxLessOperator,
TdxGreaterEqualOperator, TdxLessEqualOperator, TdxHeadOfOperator, TdxLikeOperator);
只见过array[..] or TSomeType,这种是咋回事呢？？
