Re: newbie question on singleton class

James Kanze <>
12 May 2007 14:43:49 -0700
On May 12, 3:53 pm, wrote:

I liked this article by Danny Kalev on the singleton design class:http://=

However I was confused by this:

The class's implementation looks like this:

  Singleton* Singleton::pinstance = 0;// initialize pointer
  Singleton* Singleton::Instance ()
    if (pinstance == 0) // is it the first call?
      pinstance = new Singleton; // create sole instance
    return pinstance; // address of sole instance
    //... perform necessary instance initializations


My confusion stems from the fact that pinstance is a private static
member of Singleton.

So I would have thought that Singleton* Singleton::pinstance = 0;
violates private access.

Why? It's the definition of pinstance, so it is a member of
Singleton. And it doesn't access anything (but it could---since
pinstance is a member, its initialization has the right to
access private data).

James Kanze (Gabi Software) email:
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