sso tradeoffs

[Gabriel Dos Reis]

Howard Hinnant <hhinnant@apple.com> writes:

| This is just a heads up, and probably an obvious one at that, but I
| thought I'd err on the side of repetitiveness:
| 
| When we do an sso string (as the official std::string), we at the
| same time need an extension non-mutable string whose copy constructor
| can't throw (probably via refcounting).  This will be needed in the
| <stdexcept> classes (which currently use std::string).

Agreed.  A real string, you mean :-)

-- Gaby