Inherit from Singleton

[Lou Arnold]

I need a bit of help with the use of the Singleton pattern. The classic code is shown below and I understand it well.

What I don't understand is how to turn a normal class into a singleton class without coding all the singleton constructs.

The code below, of course, generates the following compiler error because the Singleton's constructors are all private. But what is the proper class code for constructors if the Singleton constructors are all left private?

Compiler error: d:\visual studio express\visual studio 2005\projects\singletontest1\singletontest1\check.cpp(2) : error C2248:
'Singleton::Singleton' : cannot access private member declared in class 'Singleton'

---------------------------------------------
In the Singleton.h file:
---

class Singleton
{
public: 
    static Singleton* Instance();
private:
	Singleton();
	Singleton(const Singleton&);
   	static Singleton* _instance;
};

-----
and the Singleton.cpp file:
-----

#include "Singleton.h"
Singleton* Singleton::_instance = 0;

Singleton::Singleton(){};
Singleton::Singleton(const Singleton&){};

Singleton* Singleton::Instance() {
    if (_instance == 0) {
        _instance = new Singleton;
    }
    return _instance;
}

------------------------------------------------
And the check.h file:
----

#include "singleton.h"

class Check : public Singleton
{
public:
	Check(void);
};

--------
The Check.cpp file:
-------

#include "Check.h"
Check::Check(){};

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