Re: Policy-based vector? [was: Submission: Fixed-Capacity STL Containers Library]

From: rwgk (rwgk_at_[hidden])
Date: 2002-02-06 13:39:39

--- In boost_at_y..., Beman Dawes <bdawes_at_a...> wrote:
> Andrei's argument for a single policy based vector rather than 
several 
> vector classes is a powerful one.  Actually seeing a proposal for 
what 
> those policies might achieve would make it easier to form a final 
> opinion.  Policies that no one ever uses just get in the way.  But 
policies 
> that are really useful become a killer argument, IMO.

What are the fundamental differences between policy based
implementations and implementations of separate types?

From the user's perspective, I find it much more convenient
to refer to std::vector<T> and fix_cap_vector<T> rather than
generic_type<T, something_else>. To me the choice of
policy-based vs. other approaches seems to be an implementation
detail that should be hidden from the user.
Unfortunately, ISO C++ does not seem to provide the means
to achieve this for policy-based types (see
http://groups.yahoo.com/group/boost/message/24334).

Ralf