How to pass a set of different kinds of templated components to a function?-CodePudding

I have components:

struct ComponentStorage : Storage{
    ...
};

template<typename T = ComponentStorage>
class Component{
public:
T* storage;
...
}

There are derived classes of the form:

struct Component2Storage : Storage{
    ...
};

template<typename T = Component2Storage>
class Component2 : public Component<T>{...}

There are multiple levels of inheritance both for Component and for Storage.

My question has to do with functions that with take a Component as input, for example:

void myFunction(unordered_set<Component*> components){...} // This won't compile

How do I modify my function so I can pass a set containing different kinds of components which may be using different kinds of storage? The actual function doesn't treat different kinds of components differently.

CodePudding user response：

If you need to store different components in the same container, you need polymorphism.

So you need your Components to have a common base class, to be able to treat them as such.

struct ComponentStorage : Storage{
    ...
};

class ComponentBase {
    // ... define your common interface
}

template<typename T = ComponentStorage>
class Component : public ComponentBase{
public:
T* storage;
...
}

Now you could treat all components as ComponentBase* and handle them through the common interface defined.

Storing a std::variant<...all the component types> or std::any in the set could also be an option, but it comes with it's own set of pros and cons.