Defined in header
explicit facet( std::size_t refs = 0 );
facet(const facet&) = delete;
1) creates a facet with starting reference count
refs is non-zero, the facet will not be deleted when the last locale referencing it goes out of scope. A facet with static or dynamic storage duration should always be constructed with a non-zero
2) copy constructor is deleted; std::locale::facet is not copyable.