Re: [boost] Proposal: Monotonic Containers

Subject: Re: [boost] Proposal: Monotonic Containers
From: Frank Mori Hess (frank.hess_at_[hidden])
Date: 2009-06-09 14:40:49

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On Tuesday 09 June 2009, Ross Levine wrote:
> To summarize, std::vector<T, monotonic_allocator<T> > won't work if each
> vector gets a specific buffer, because another vector could possibly use
> that buffer instead! Thus a custom version of each container is REQUIRED
> unless there's a boost.test macro BOOST_STL_ALLOCATOR_EQUIVALENCE or
> something like that.

It seems like you could make a stack-backed vector work in c++03 by building 
it on top of something like

std::vector<object_wrapper<T>, monotonic_allocator<T> >

where object_wrapper<T> contains the T value plus a pointer to an object that 
holds the needed per-container allocator state.  That gets you around the 
stateless allocator problem at the expense of having to store an extra 
pointer for each object in your container.

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