Re: Alexandrescu MC++D: SmallObjAllocator problem

From:

"Alf P. Steinbach" <alfps@start.no>

Newsgroups:

comp.lang.c++.moderated

Date:

Sat, 12 May 2007 20:59:53 CST

Message-ID:

<5amfu0F2p96qpU1@mid.individual.net>

* Alf P. Steinbach:
> The old copy of Loki that I have includes, in SmallObject, the comment

   // The typedef below would make things much simpler,
   // but MWCW won't like it
   // typedef SingletonHolder<MySmallObjAllocator/*, CreateStatic,
   // DefaultLifetime, ThreadingModel*/> MyAllocator;

and instead uses

   struct MySmallObjAllocator : public SmallObjAllocator
   {
       MySmallObjAllocator()
       : SmallObjAllocator(chunkSize, maxSmallObjectSize)
       {}
   };

Correction. It doesn't use a typedef or derived class at all, but
specifies the instantiation directly in the calls, like

     return SingletonHolder<MySmallObjAllocator, CreateStatic,
         PhoenixSingleton>::Instance().Allocate(size);

That's so ugly that it didn't occur to me that it could be, so I misread
the code.

Happily this is very old code; no doubt current compilers can handle a
typedef with no problem.

Cheers,

- Alf

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