Re: Private constructor

From: Matej Pivoluska (spam_at_spam.com)
Date: 12/14/03 

Date: Sun, 14 Dec 2003 17:10:49 +0100

Andy wrote:

> 1) Is there any use of defining a class with a single constructor
> declared in private scope? I am not asking a about private copy
> constructors to always force pass/return by reference.
>
> 2) Is this in any way used to create singletons. Can someone say how?

If you want to create singletons, you have to declare all your constructors
(and operator=, too) as private.

Then you create a public function that checks if singleton was created
(through some static bool member) and then calls (private) constructor.

Then (if check passed) your function returns refernece (or pointer) on your
singleton and set true flag to static member -- singleton was created. 

-- 
mP
http://pivoluska.matfyz.cz/

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