如何在C ++中实现Swift枚举关联的值？

Question

In Swift I'm implementing a state machine where the current state is represented by an enum value. I associate extra data of varying types with each enum value. Is there a way to do this in C++? I can only think of using inheritance of some State class, but I would later have to use some kind of reflection and cast the State objects to get the extra associated data.

Answer 1

One way is to have a base class representing the enum, and subclasses for each of the cases (each class having variables for the associated value for that case). The base class should be polymorphic (have at least one virtual method; probably a virtual destructor), so that the "enum" can be deconstructed by testing it against each case using dynamic_cast .