From: Paul Brannan <pbrannan@...>
Date: 2004-01-16T00:25:03+09:00
Subject: Re: Nested scopes and the Singleton pattern

On Thu, Jan 15, 2004 at 06:39:13PM +0900, nobu.nokada@softhome.net wrote:
> At Thu, 15 Jan 2004 13:55:44 +0900,
> Hal Fulton wrote:
> > > Just using Thread.critical.  And seems close to your idea
> > > excepting for it uses "instance" method rather than "new".
> 
> Not accurate, it uses 3-state; before, during and after
> creation, but I feel it should use mutex or something.

I think I agree.  It took me an hour to understand the Singleton code
last time I read it, and when I look at it again now, I seem to have
forgotten how it works.

It seems like using a Mutex plus Thread.exclusive around the code that
redefines instance() should be sufficient, but perhaps I'm missing
something.

Paul