language: C++11 (gcc-4.7.2)
date: 185 days 3 hours ago
link:
visibility: private 
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class B;
class C;
 
class A{
public:
    virtual bool operator<(const A & object) const = 0; // I assume you only care about B and C
    virtual bool operator<(const B & object) const = 0; // I assume you only care about B and C
    virtual bool operator<(const C & object) const = 0; // I assume you only care about B and C
};
 
class B: public A{
public:
    virtual bool operator<(const A & object) const
    {
        // do a second bind, now that we know this is type B. Negate cause we
        // are switching the operands.
        return !object.operator<( (const B&)*this);
    }
    virtual bool operator<(const B & object) const
    {
        return true;
    }
    virtual bool operator<(const C & object) const
    {
        return true; // B is always < than C right?
    }
};
 
class C: public A{
public:
    virtual bool operator<(const A & object) const
    {
        // do a second bind, now that we know this is type C. Negate cause we
        // are switching the operands.
        return !object.operator<( (const C&)*this);
    }
    virtual bool operator<(const B & object) const
    {
        return false; // C is always > then B right?
    }
    virtual bool operator<(const C & object) const
    {
        return true;
    }
};
 
int main() {
   A* a1 = new B();
   A* a2 = new C();
   bool r = *a1 < *a2;
}