Re: newbie question on singleton class
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).
--
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