Function format

extern/boost/boost/timer/timer.hpp:64–65

does not stop()

    bool          is_stopped() const BOOST_NOEXCEPT              { return m_is_stopped; }
    cpu_times     elapsed() const BOOST_NOEXCEPT;  // does not stop()
    std::string   format(short places, const std::string& format) const
                        { return ::boost::timer::format(elapsed(), places, format); }
    std::string   format(short places = default_places) const
                        { return ::boost::timer::format(elapsed(), places); }
    //  actions