/** @file list6302.cpp */
/** Listing 63-2. Changing the Inheritance of Visible to Virtual */
#include <iostream>
#include <ostream>
#include <string>

class visible {
public:
    visible(std::string const& msg) : msg_(msg) { std::cout << msg << '\n'; }
    std::string const& msg() const { return msg_; }
private:
    std::string msg_;
};

class base1 : virtual public visible {
public:
   base1(int x) : visible("base1 constructed"), value_(x) {}
   int value() const { return value_; }
private:
   int value_;
};

class base2 : virtual public visible {
public:
   base2(std::string const& str) : visible("base2(" + str + ") constructed") {}
};

class base3 : virtual public visible {
public:
   base3() : visible("base3 constructed") {}
   int value() const { return 42; }
};

class derived : public base1, public base2, public base3 {
public:
   derived(int i, std::string const& str)
   : base3(), base2(str), base1(i), visible("derived")
   {}
   int value() const { return base1::value() + base3::value(); }
   std::string msg() const
   {
     return base1::msg() + "\n" + base2::msg() + "\n" + base3::msg();
   }
};

int main()
{
   derived d(42, "example");
   std::cout << d.value() << '\n' << d.msg() << '\n';
}