I think I was not clear about `const` :/ I mean `virtual unsigned int supportedLanguages() const;`.
I wonder if we can't replace this virtual method by the flag in the constructor (as in the Test).

I may see some possible rules specific to C++11 (For example for non-copyable classes, detect unimplemented private copy constructor (c++98's way), and instead propose to use public copy constructor `= delete`(c++11's way)).
it is maybe too early to add this now, but it should be possible for the future. So, wait for C++11 rules.