Re: newbie question on singleton class

From:
James Kanze <james.kanze@gmail.com>
Newsgroups:
comp.lang.c++
Date:
12 May 2007 14:43:49 -0700
Message-ID:
<1179006229.837000.53990@o5g2000hsb.googlegroups.com>
On May 12, 3:53 pm, pauldepst...@att.net wrote:

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

gethelp.devx.com/techtips/cpp_pro/10min/10min0200.asp

However I was confused by this:

QUOTE BEGINS HERE
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
  }
  Singleton::Singleton()
  {
    //... perform necessary instance initializations
  }

QUOTE ENDS HERE

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: james.kanze@gmail.com
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