On Mon, Jan 21, 2013 at 9:50 PM, Jeffrey Lee Hellrung, Jr. <jeffrey.hellrung@gmail.com> wrote:
I would expect sizeof( static_vector ) < sizeof( hybrid_vector ) (even with EBO used for storing the allocator in the latter case), as hybrid_vector needs to discriminate between using internal and using external storage. Additionally, this will sometimes necessitate more branching and/or indirection in hybrid_vector than in static_vector for the same operation. Well, really, that's all just a guess, I haven't actually gone and implemented each myself. And it's assuming that hybrid_vector< T, N, null_allocator<T> > isn't special-cased to behave like a static_vector<T,N>, because, at that point, now we're just arguing over names.
Given that hybrid functionality is desired too I think it makes sense to provide it. Then, if static vector really can't be provided efficiently as a case of hybrid_vector could you implement static vector.
I would expect sizeof( static_vector ) < sizeof( hybrid_vector )
as hybrid_vector needs to discriminate between using internal and using external storage.
That's just a single bit. Olaf