Template class override base class virtual function

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0

Consider the following code:

class Base
{
public:
    virtual void* allocate(){ return nullptr; }
};

template <class T> class BaseTemplate : public Base
{
public:
    void* allocate() override { return new T(); }
};

class IntSpecialization : public BaseTemplate<int>
{
};

Base GetSpecialization(const int&){ return IntSpecialization(); }

The goal is to be able to use template to implement specializations, but still allow users to work using the base class interface, such as:

int a;
auto s = GetSpecialization(a);
auto p = s.allocate();

The above code does not work; s.allocate() always return nullptr for obvious reasons.

I absolutely need the GetSpecialization function to return the Base non-template class, so how do I go about this?

The Base class virtual method cannot be pure, because otherwise it becomes abstract and it will fail the compilation at GetSpecialization.

What is the best approach to solve this pattern? Using C++11? Thanks!

asked 1 min ago

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