Re: Singleton_pattern and Thread Safety

From:
James Kanze <james.kanze@gmail.com>
Newsgroups:
comp.lang.c++
Date:
Fri, 10 Dec 2010 07:29:41 -0800 (PST)
Message-ID:
<60d19d84-852c-460a-b3e7-a64106aa6069@i17g2000vbq.googlegroups.com>
On Dec 10, 1:16 pm, Leigh Johnston <le...@i42.co.uk> wrote:

On 10/12/2010 09:52, James Kanze wrote:

On Dec 9, 5:05 pm, Marcel M ller<news.5.ma...@spamgourmet.com> wrote:

Pallav singh wrote:


    [...]

Note that the above still risks order of destruction issues;
it's more common to not destruct the singleton ever, with
something like:

     namespace {

     Singleton* ourInstance =&Singleton::instance();

     Singleton&
     Singleton::instance()
     {
         if (ourInstance == NULL)
             ourInstance = new Singleton;
         return *ourInstance;
     }
     }

(This solves both problems at once: initializing the variable
with a call to Singleton::instance and ensuring that the
singleton is never destructed.)


James "Cowboy" Kanze's OO designs includes objects that are never
destructed but leak instead?


And where do you see a leak?

Interesting. What utter laziness typical
of somebody who probably overuses (abuses) the singleton pattern.


A lot of unsupported accusations from someone whose postings
here show a remarkable lack of any knowledge of serious software
engineering.

Singleton can be considered harmful (use rarely not routinely).


Does two or three in a program of 500KLoc count as "routinely"?

--
James Kanze

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