Re: [boost] Container Adaptors

From: Herve Bronnimann (hbr_at_[hidden])
Date: 2002-10-17 13:31:26

On Thu, Oct 17, 2002 at 02:08:59PM -0400, David A. Greene wrote:
> I've often found the need to construct container adaptors to provide
> things such as a fixed-size vector.  After once again writing
> some of these things, I'm wondering whether it might be worth
> designing a container adaptor library similar to the iterator
> adaptor library.  I can see a container traits library coming
> out of this as well.

David: 

I assume that by fixed-size vectors your mean a sequence container where
all the operations insert/erase have been made inacessible?
imho you don't need a container adaptor for fixed-size vector. You
should rewrite your code to use a range [first,last) instead.

Granted you can't pass a range as a single object, but Jeremy Siek has
written (in the boost-sandbox) a series of container algorithms that
take a pair<iterator,iterator> (representing a range) and applying
standard library functions to the pair. It's pretty usable (he uses it
in the BGL IIRC, but don't take my word for it, go look!)

For instance: begin(Vector&) or begin(pair<iter,iter>&) will give you
the beginning of the range. Enables you to write generic algorithms.

I'm really unclear as to what a container adaptor library would provide
(are you thinking of something along the lines of std::stack,
std::queue, and std::priority_queue?)  I'm pretty convinced that
fixed-size vectors would encourage using the wrong solution style, but
they are a convenience, and some people can't live without a certain
level of it. Other adaptors may be more useful, would you have a few
suggestions?

> Is there something currently in Boost that will allow me to do
> these sorts of things?  If not, is this something the Boost
> community would be interested in?

Check out:
boost-sandbox/boost/sequence_algo/container_algo.hpp
-- 
Herve'