Re: Singleton Pattern without Static Method

From:
James Kanze <kanze.james@neuf.fr>
Newsgroups:
comp.lang.c++.moderated
Date:
5 Jun 2006 19:21:20 -0400
Message-ID:
<e61lka$fce$1@nntp.aioe.org>
Valentin Samko wrote:

Venkata.Nanduri@gmail.com wrote:

      I have been trying to understand if there's a way to implement
Singleton Pattern without Using Static Methods?


= myfile.h =
   class Singleton { ... };
   Singleton* getInstance();

= myfile.cpp =
   Singleton s;
   Singleton* getInstance() { return &s; }

Of course one can not safely use this before "main", but one
can use a nifty counter or other techniques to address this
issue.


It will also cause problems as soon as you use the idiom for
more than one class -- you need some sort of naming convention.

Also, of course, it's not a singleton. There's nothing to
prevent a user from declaring a local instance.

In answer to his question, you can always use a friend function
instead of a static member. But why bother? Or more to the
point, what's the real difference?

--
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