C / C++ / MFC

#include <iostream>
#include <bitset>

int main(int argc, char* argv[])
{
    unsigned long data = 59;
    int nCount = std::bitset<32>(data).count();

    std::cout << nCount << endl;
    return 0;
}

#include <iostream.h>
#include "header.h"
//declaration
template <class T> class temp
{
public:
    class nested
        {
        public:
            void test()
			{
				cout << "Hello world"<< endl;
			}
        };

    void test()
    {
        nested nes;
        nes.test();
    }
};

int main( /* int argc, char* argv[] */ )
{
    temp<int> tem;
    tem.test();
    return 0;
}

Thank all.

I have try it in
C++ Builder. It runs well there.

I could have
defined the function within the class declaration. However, I am not able to do
that. The reason is illustrated by the following example. In the example, A<T>::nested uses B<T> and B<T>::nested used A<T>.

// begin of A.h

#pragma once

 // foreword
declaration, but we still can not use class B.

//that is why I can't put the definition of A<T>::nested::test() inside
the declaration;

template <class T> class B;

template <class
T> class A

{

public:

   
class nested

   
{

     
public:

       
void test(B<T> b);

   
};

  
nested GetNested() const

   
{

return nested();

   
}

}

#include A.imp

// end of A.h

//A.imp

#pragma once

#include B.h //
now we can use class B

template <class
T> void A<T>::nested::test( B<T> b)

{

       
b.GetNested();

}

//end of A.imp

//begin of A.cpp

#include A.h //the
only one line in A.cpp

//end of A.cpp

// B.h

#pragma once

 // foreword
declaration, but we still can not use class A.

//that is why I can't put the definition of B<T>::nested::test() inside
the declaration;

template <class
T> class A; // foreword declaration

template <class
T> class B

{

public:

   
class nested

   
{

     
public:

       
void test(A<T> b);

   
};

  
nested GetNested() const

   
{

return nested();

   
}

}

#include B.imp

// end of B.h

//B.imp

#pragma once

#include A.h

template <class
T> void B<T>::nested::test( A<T> a)

{

a.GetNested();

}

//end of B.imp

//begin of B.cpp

#include B.h //the
only one line in B.cpp

//end of B.cpp

The result is that
this situation force me not to use nested class.

What a pity. My
logical design is forced to change by a bug.;( Or I have to change my compiler.

-Masaaki Onishi-