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// 
// I am not sure how to interprate the ARM (or the Draft C++ Standard) 
// with regard to the initialization of a virtual base class. I have tried 
// some examples on a DEC C++ compiler, but I am not sure whether the results 
// are o.k. Could anybody give me some details?
//
// Benedikt Weber, Swiss Federal Institute of Technology, Zurich
// weber@ibk.baum.ethz.ch
//*************************************************************************
// Here some problems initializing a virtual base class V
// The results indicated were obtained with the DEC C++ compiler

#include <iostream.hxx>

class V{
public:
    V(int i) {cout << "init V(int)" << endl;}
    V() {cout << "init V()" << endl;}
};

class A: virtual public V{
public:
    A() {}
    A(int i): V(i) {}
};

class B: virtual public V{
};


class C1: public A, public B, virtual public V{
public:
    C1(int i): A(i) {}
};

// C1 is similar to the ARM example at the end of Section 12.6.2
// and works correctly. V is initialized directly by the most derived class
// C1 as V(). My example prints correctly "init V()"


class C2: public A, public B{
public:
    C2(int i): A(i){}
};

// C2 is not directly derived from V. In this case I don't think the base
// class should still be initialized by the most derived class. Rather
// C2 should initialize A(i) which in turn sould initialize V(i).
// This would be in accordance with the example in the ARM in Section 12.6.2
// where the order of initializatoin is explained. However, the ARM is not
// quite clear in this point and it could be a question of interpretation.
// 
// My example prints "init V()", i.e. it initializes V directly from
// C2, which seems not correct to me.
//

class C3: public A, public B{
public:
    C3(int i): V(i){}
};

// C3 is not directly derived from V. Nevertheless it does initialze V(i)
// and the example prints "init V(int)". I wonder whether this is correct
// because I think a class can only initialize it's direct base classes.

int main(){
    C1(1);
    C2(2);
    C3(3);
}
---
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