Nested Classes - Namespaces

[xgiovio]

/*

    a is a class
        a1 and b are public subclass of class a
            b inherit the class a1
        c is a private subclass of class a


*/


/////////////////////// the inteface
class a{
public:
    a();
    int var;
    class a1{
    public:
        a1( int in);
    };
    class b : public a1 {
    public:
        b(int in);
    };
    a::a1 mario;
private:
    class c{
        c();
    };
    c obj; // i  can create a class c obj because i'm in the class a
    b obj2;// b is a public subclass, i can create an object here and out of here
};

///////////////////// the implementation
a::a()
    :var(0),
    mario(10)
{}

a::a1::a1(int in)
{}

a::b::b(int in)
    :a1(in)
{}

a::c::c()
{}



////////////////// main sample

int main () {

    a obj1; // a in a general class
    a::a1 obj2(10); // a1 is accessible because it's a public subclass of a
    a::b  obj3(10); // ab is accessible because it's a public subclass of a

    a::c obj4; // error - c is a private subclass of a, i can declase a c object only as a class a member

}