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From: Howard Hinnant (hinnant_at_[hidden])
Date: 1999-11-23 15:33:09

In a std::container memory can not allocated be allocated by new.
Instead an Allocator class is passed in as a template parameter and
optionally through the contructor as well. So internal to vector for
example you might have code that looks like:

                                        data_ = alloc_.allocate(n);
     capacity_ = n;
                                        alloc_.deallocate(data_, capacity_);

I was hoping to do something more like:

     data_.reset(data_.allocate(n), n);

or something like that. Haven't had time to really work out the details.
 But what you suggest below is really what I'm after: The ability to use
"auto_ptr" in the implementation. this "auto_ptr" will have to use the
vector's allocator to deallocate the memory. And the vector's allocator
needs the capacity sent to the deallocate method.

Might be a dead end, don't know yet...


Michel André wrote on 11/23/99 3:15 PM
>> This is just a scoped_ptr with a capacity thrown in that it can hand back
>> to Allocator::deallocate. Note that scoped_ptr may be useful as is for
>> use in node based standard containers because it passes "1" in
>> Allocator::deallocate. Again, haven't actually implemented a standard
>> container in terms of one of these. Just exploring the possibility.
>I really don't see the use of this but maybe you could enlighten me?
>Couldnt the standard containers be implemented with an scoped_array or
>an auto_ptr with an array deallocator?

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