Convert to Polymorphism?

From:

Immortal Nephi <Immortal_Nephi@hotmail.com>

Newsgroups:

comp.lang.c++

Date:

Mon, 27 Apr 2009 19:57:46 -0700 (PDT)

Message-ID:

<5d3a0d30-c67f-44f0-95cd-cdd7333e1976@x29g2000prf.googlegroups.com>

    Each derived classes are derived from class A through virtual
multiple inheritance. Only class E is defined. Each data members and
member functions are inherited into class E from one base class and
all derived classes.
    Each derived classes have the same Run() member function name, but
different implementation. The variable of pFunc_E is a pointer to Run
() member function. It does not have pointer to member function array
because I want to reassign any Run() member function to pFunc_E at run-
time execution.
    pFunc_E is like dispatch function. Inheritance is the answer to
divide from one large base class into derived sub-classes (from one
large source code to multiple source code for better readability).
Class E is used to communicate to all sub-classes.
    Please tell me if one object with multiple sub-classes good design.
If not, can it be converted to polymorphism? Run() can be set to pure
virtual function in class A and (non-pure) virtual functions to all
derived sub-classes. What is your advice? Please give me your
example if you can. Thanks=85

class E;

class A
{
public:
    A();
    ~A();
    void Run_A();
    void (E::*pFunc_E)();
    void Test();
};

class B1 : virtual public A
{
public:
    B1();
    ~B1();
    void Run_B1();
};

class B2 : virtual public A
{
public:
    B2();
    ~B2();
    void Run_B2();
};

class B3 : virtual public A
{
public:
    B3();
    ~B3();
    void Run_B3();
};

class B4 : virtual public A
{
public:
    B4();
    ~B4();
    void Run_B4();
};

class C1 : virtual public B1, virtual public B2, virtual public B3,
virtual public B4
{
public:
    C1();
    ~C1();
    void Run_C1();
};

class C2 : virtual public B1, virtual public B2, virtual public B3,
virtual public B4
{
public:
    C2();
    ~C2();
    void Run_C2();
};

class C3 : virtual public B1, virtual public B2, virtual public B3,
virtual public B4
{
public:
    C3();
    ~C3();
    void Run_C3();
};

class D1 : virtual public C1, virtual public C2, virtual public C3
{
public:
    D1();
    ~D1();
    void Run_D1();
};

class D2 : virtual public C1, virtual public C2, virtual public C3
{
public:
    D2();
    ~D2();
    void Run_D2();
};

class E : virtual public D1, virtual public D2
{
public:
    E();
    ~E();
    void Run_E();
};

A::A() {}
A::~A() {}
void A::Run_A() {}
void A::Test() {}

B1::B1() {}
B1::~B1() {}
void B1::Run_B1() { pFunc_E = &B2::Run_B2; }

B2::B2() {}
B2::~B2() {}
void B2::Run_B2() { pFunc_E = &B3::Run_B3; }

B3::B3() {}
B3::~B3() {}
void B3::Run_B3() { pFunc_E = &B4::Run_B4; }

B4::B4() {}
B4::~B4() {}
void B4::Run_B4() { pFunc_E = &C1::Run_C1; }

C1::C1() {}
C1::~C1() {}
void C1::Run_C1() { pFunc_E = &C2::Run_C2; }

C2::C2() {}
C2::~C2() {}
void C2::Run_C2() { pFunc_E = &C3::Run_C3; }

C3::C3() {}
C3::~C3() {}
void C3::Run_C3() { pFunc_E = &D1::Run_D1; }

D1::D1() {}
D1::~D1() {}
void D1::Run_D1() { pFunc_E = &D2::Run_D2; }

D2::D2() {}
D2::~D2() {}
void D2::Run_D2() { pFunc_E = &B1::Run_B1; }

E::E() {}
E::~E() {}
void E::Run_E() {}

int main()
{
    E e[3];

    e[0].pFunc_E = &B1::Run_B1;
    e[1].pFunc_E = &B1::Run_B1;
    e[2].pFunc_E = &B1::Run_B1;

    for (int y = 0; y < 3; y++)
    {
        for (int x = 0; x < 10; x++)
            (e[y].*(e[y].pFunc_E))();
    }

    system("pause");

    return 0;
}