约束枚举子类型

Question

是否可以在不使用范围而是使用特定值的情况下在Ada中约束Enum类型？例如：

type Rainbow is (Red, Orange, Yellow, Green, Blue, Indigo, Violet);
subtype Red_Green is Rainbow range Red .. Green; -- Example with range
subtype Stop_Light is Rainbow Red, Yellow, Green; -- Is this possible?