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    <p>Another way to do that is through <a href="http://en.wikipedia.org/wiki/Curiously_recurring_template_pattern" rel="nofollow">CRTP</a> and operator overloading helpers (Like <a href="http://www.boost.org/doc/libs/1_53_0/libs/utility/operators.htm" rel="nofollow">boost operators header</a>)</p> <p>Suposse you have the following helper:</p> <pre><code>template&lt;typename T&gt; struct AddHelper { T&amp; operator++() { T&amp; reference = static_cast&lt;T&amp;&gt;(*this); reference.add(); return reference; } T operator++(int) { AddHelper&lt;T&gt; copy( *this ); operator++(); return static_cast&lt;T&gt;(copy); } }; </code></pre> <p>The <strong>add()</strong> implementation is provided by the base class:</p> <pre><code>class Vehicle { private: int _n; public: void add(int n) { _n += n; } ... }; </code></pre> <p>Because <code>Vehicle::add()</code> is public, we can use it in every Vehicle subclasses, thats means you can have <strong>specific operator++ for every Vehicle subclasses</strong> thanks to AddHelper:</p> <pre><code>class Car : public Vehicle , public AddHelper&lt;Car&gt; { Car(int n) : Vehicle(n) {} ... }; class Motorcicle : public Vehicle , public AddHelper&lt;Motorcicle&gt; { Motorcicle(int n) : Vehicle(n) {} ... }; class Bus : public Vehicle , public AddHelper&lt;Bus&gt; { Bus(int n) : Vehicle(n) {} ... }; ... //Ad infinitum </code></pre> <p>Another advantage of this way is that it doesnt use virtual functions to provide the polymorphism, so its more efficient (Static polymorphism instead of dynamic polymorphism).</p>
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    1. POC++ operator overloading with inheritance
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    1. CO`Car c(10); c++;` how will `c` determine which `operator++(int)` to call? `AddHelper<Car>::operator++` or `AddHelper<Vehicle>::operator++`?
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    2. CO@prongs `Car` inherits from `AddHelper<Car>`, so in that template instantation, T is Car. That means if you call **Car::operator++()** you are calling **AddHelper<Car>::operator++()**. And, if for example, you call Bus::operator++(), you are really calling AddHelper<Bus>::operator++().
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    3. CO@prongs The trick is that because you inherit from a template, that template is specific of your class. In other words, **the compiler generates one operator++ for every class that inherits from AddHelper**.
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