同时管理指针向量和对象向量的模板类

Question

I have two template class that are very similar: one manages a vector of T* objects and does things to these pointers, another manages a vector of T objects and does the same thing to these objects.

Is there some way I can have a single class that manages either a list of pointers or a list of objects?

Answer 1

Yes. Interact with the members of your vector via a helper functor that turns T& into T* in the value case. Any other behavior differences can be similarly factored into traits/helper types and handled similarly.

Take the functor as an additional template parameter to your template . Possibly hide it by having two public template s that pass the appropriate helper functor to the implementation template .

In extremely simple cases, you could do away with the functor, and just use overloading on pointers vs references.

Answer 2

Yes. Use a template specialization :

First, declare the class as you would normally:

template <typename T>
class Foo
{
     ...
};

Then declare a specialization for pointer types:

template <typename T>
class Foo<T*>
{
    //re-define any methods you want to be different for the pointer implementation.
};

The class can then be used normally, but if the template parameter is a pointer type, it will use the T* implementation:

Foo<Bar> fooBar; //uses the default implementation
Foo<Bar*> fooPbar; //uses the specialized implementation