Function value

extern/boost/boost/optional/optional.hpp:1295–1301

#if (!defined BOOST_NO_CXX11_REF_QUALIFIERS) && (!defined BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES)
    reference_const_type value() const&
      {
        if (this->is_initialized())
          return this->get() ;
        else
          throw_exception(bad_optional_access());
      }

    reference_type value() &
      {