The Status of Const

[dsimcha]

== Quote from Andrei Alexandrescu (SeeWebsiteForEmail at erdani.org)'s article
> Steven Schveighoffer wrote:
> > Hopefully, Andrei will eventually get around to dealing with const in
> > std.container and see what a mess it will become without some sort of
> > tail-const for ranges.
> I believe at some point an approach will come forth. Here are a few
> quick thoughts on this large exchange:
> * The discussion this time around reflects a deep and thorough
> understanding of the issues involved throughout the community.
> * I think head-const has its usefulness, and tail-const is obviously in
> need for serious attention. Ideally we should reach, with no or minimal
> language changes, the point at which full const is the built-in power
> tool and head-const and tail-const are library artifacts. I think it's
> quite easy to define a Final!T template that is head-const, and
> Rebindable!T is a starting point for tail-const classes. We need to
> figure a pattern for achieving tail constness for general types.

Forgive me for replying to a post that's over a month old, but I was just thinking
about this.  The only problem I see with making Rebindable a limited form of
general tail const is the issue of structs with elaborate assignment.  Do you have
any tricks up your sleeve for dealing with this?