crtp example from blog entry http://blog.cdleary.com/2012/01/c-generic-wrappers-and-crtp-oh-mi/

crtp_example.cpp

struct Cake {
    static Cake Fail;

    bool burned();
};

Cake Cake::Fail;

struct Ingredients { bool spoiled(); };
struct BatterAndWhatnot {};

template <class Wrapped>
class CakeMaker
{
  public:
    Cake makeCake() {
        Wrapped *self = static_cast<Wrapped *>(this);
        Ingredients ingredients = self->fetchIngredients();
        if (ingredients.spoiled())
            return Cake::Fail;

        BatterAndWhatnot batter = self->mixAndStuff(ingredients);
        Cake result = self->bake(batter);
        if (result.burned())
            return Cake::Fail;

        return result;
    }
};

class PersonalChef : public CakeMaker<PersonalChef>
{
    Ingredients fetchIngredients();
    BatterAndWhatnot mixAndStuff(Ingredients);
    Cake bake(BatterAndWhatnot);

    friend class CakeMaker;
};

int main()
{
    PersonalChef chef;
    chef.makeCake();
    return 0;
}