Re: C++ singleton pattern question

From: Noah Roberts (nroberts_at_stmartin.edu)
Date: 02/22/05 

Date: 22 Feb 2005 09:54:41 -0800

ferdinand.stefanus@gmail.com wrote:
> Hi
>
> Could someone tell me what's the difference between these two
singleton
> implementations:

You don't control initialization in the first case. In the second case
you do.

I usually do something like this:

class Singleton
{
  Singleton *instance;
  Singleton() {}
public:
  void function1() { blah; }
  static void function1 { if (instance == NULL) instance = new
Singleton();
                          instance->function1(); }
};

in Singleton.cpp:
Singleton *Singleton::instance = NULL;

I don't know off hand if C++ allows static and non-static functions to
have same signature...you may have naming issues w/ regard to above.
It is the basic structure that is important. You will probably want a
const accessor also.

Relevant Pages

  • Re: Writing Singleton Classes
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  • Singleton Implementation Issue
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  • Re: question: static objects in LIB
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    (microsoft.public.vc.language)