Specializations of std::char_traits

[Gabriel Dos Reis]

Matt Austern <austern@apple.com> writes:

|   2. I deliberately avoided standard algorithms like std::copy and
| std::fill_n.  Rationale: at present, bits/char_traits.h is almost
| self-contained.  It depends on <cstring> and bits/fpos.h and nothing
| else.  I don't want to introduce a new dependence unless there's a
| very strong reason for it.

The only way to get std::char_traits<> is by including <string>, which
already has much  more dependencies.  In fact, I'm not really
convinced by the dependency argument vs. reusing standard algorithms.
Actually, std::copy and std::fill_n already have logics in place to
provide better optimization  where possible.  I would not recommend we
don't take the opportunies to reuse them.

-- Gaby