In C++, template inheritance allows us to create classes that inherit from a base template and specialize it further. This allows for a powerful way to define reusable code. However, sometimes we may need to have templates that inherit from other templates. This is where recursive templates come into play.

Recursive templates in C++ allow us to define templates that inherit from other templates, forming a hierarchy. This can be useful when we want to create a hierarchy of specialized templates, where each template can further specialize the behavior of its parent template.

To illustrate this concept, let’s consider an example of a Base template that defines a generic type:

template <typename T>
class Base {
    // Class implementation goes here
};

We can now create a derived template Derived that inherits from Base:

template <typename T>
class Derived : public Base<T> {
    // Class implementation goes here
};

Now, let’s define another template FurtherDerived that inherits from Derived:

template <typename T>
class FurtherDerived : public Derived<T> {
    // Class implementation goes here
};

This creates a recursive chain of template inheritance. Each derived template specializes the behavior of its parent template.

To use these recursive templates, we can instantiate them with specific types:

Base<int> baseInstance;
Derived<double> derivedInstance;
FurtherDerived<std::string> furtherDerivedInstance;

Each instance will have the behavior defined by its respective template, including any specialized behavior inherited from its parent template.

Recursive templates provide a powerful way to create hierarchies of specialized templates in C++. They allow for code reuse and enable us to define complex relationships between templates. By utilizing template inheritance, we can build flexible and extensible code structures.

#cpp #templates #inheritance