Re: [boost] Re: Re: Singleton

From: Jason Hise (chaos_at_[hidden])
Date: 2005-01-09 15:34:48

Thomas Beckmann wrote:

> Wouldn't it be easier to change AddDependency to something like the 
> following:
>
> static void AddDependency ( )
> {
>         static bool first = true;
>
>         if ( first ) {
>                 s_inst = static_cast < T * > ( A :: Create ( ) );
>                 dependents = 0;
>                 first = false;
>         }
>         ++dependents;
> }

The problem is that this makes recreating the singleton impossible... 
you lose the phoenix effect.  Also, creating the singleton might 
inadvertently result in creating something else that creates something 
else that has a singleton dependency.  If such a thing happens, 
dependents should be in a correct state ( aka incremented ) before 
create is called.

-Jason