[Dune] [Dune-Commit] dune-common r5882 - trunk/dune/common

[Oliver Sander]

Hi Christian!
How about the following compromise:  We add a new allocator
static_allocator to dune-common.  This allocator would be standard-
compliant, similar to array_allocator, but actually contain the
memory it manages.  You could then write something like (not tested)

typedef Dune::static_allocator<int,10> MyAllocator;
MyAllocator allocator;
std::{vector|set|map|whatever}<int,MyAllocator>(allocator);

This is bit simpler than the gnu array_allocator.  You could then
implement ReservedVector using this allocator, much like Carsten
suggested.  This would be a very short file, then.

Yrs,
Oliver


> As you said, you allocate your memory somewhere else. I want something
> with the memory inside. Actually your vector doesn't allocate memory
> at all.it is only a view on an other array.
>
> I give you two use cases and perhaps you can tell me how it should
> work.
>
> 1) write something like this:
>    
>    std::vector< ReservedVector<int,4> > vec;
>    for (int i=0; i<n; i++)
>      vec.push_back(ReservedVector<int,4>);
>
>    and assume that the number of elements does vary. How to handle
>    dynmic memory memory management with the allocator?
>
> 2) you store some stuff in std::vector< ReservedVector<int,4> > and
>    hand it to the user. Now the user can delete the vector and the
>    memory is freed. How so you handle memory-ownership with the
>    allocator?
>
> Perhaps I just don't get it, but I still think that the two approaches
> are substatially different.
>
> Christian
>   


-- 
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* Oliver Sander                ** email: sander at mi.fu-berlin.de        *
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