Chris@16: /* Boost interval/rounding.hpp template implementation file
Chris@16:  *
Chris@16:  * Copyright 2002-2003 Hervé Brönnimann, Guillaume Melquiond, Sylvain Pion
Chris@16:  *
Chris@16:  * Distributed under the Boost Software License, Version 1.0.
Chris@16:  * (See accompanying file LICENSE_1_0.txt or
Chris@16:  * copy at http://www.boost.org/LICENSE_1_0.txt)
Chris@16:  */
Chris@16: 
Chris@16: #ifndef BOOST_NUMERIC_INTERVAL_ROUNDING_HPP
Chris@16: #define BOOST_NUMERIC_INTERVAL_ROUNDING_HPP
Chris@16: 
Chris@16: namespace boost {
Chris@16: namespace numeric {
Chris@16: namespace interval_lib {
Chris@16: 
Chris@16: /*
Chris@16:  * Default rounding_control class (does nothing)
Chris@16:  */
Chris@16: 
Chris@16: template<class T>
Chris@16: struct rounding_control
Chris@16: {
Chris@16:   typedef int rounding_mode;
Chris@16:   static void get_rounding_mode(rounding_mode&) {}
Chris@16:   static void set_rounding_mode(rounding_mode)  {}
Chris@16:   static void upward()     {}
Chris@16:   static void downward()   {}
Chris@16:   static void to_nearest() {}
Chris@16:   static const T& to_int(const T& x)         { return x; }
Chris@16:   static const T& force_rounding(const T& x) { return x; }
Chris@16: };
Chris@16: 
Chris@16: /*
Chris@16:  * A few rounding control classes (exact/std/opp: see documentation)
Chris@16:  *   rounded_arith_* control the rounding of the arithmetic operators
Chris@16:  *   rounded_transc_* control the rounding of the transcendental functions
Chris@16:  */
Chris@16: 
Chris@16: template<class T, class Rounding = rounding_control<T> >
Chris@16: struct rounded_arith_exact;
Chris@16: 
Chris@16: template<class T, class Rounding = rounding_control<T> >
Chris@16: struct rounded_arith_std;
Chris@16: 
Chris@16: template<class T, class Rounding = rounding_control<T> >
Chris@16: struct rounded_arith_opp;
Chris@16: 
Chris@16: template<class T, class Rounding>
Chris@16: struct rounded_transc_dummy;
Chris@16: 
Chris@16: template<class T, class Rounding = rounded_arith_exact<T> > 
Chris@16: struct rounded_transc_exact;
Chris@16: 
Chris@16: template<class T, class Rounding = rounded_arith_std<T> > 
Chris@16: struct rounded_transc_std;
Chris@16: 
Chris@16: template<class T, class Rounding = rounded_arith_opp<T> > 
Chris@16: struct rounded_transc_opp;
Chris@16: 
Chris@16: /*
Chris@16:  * State-saving classes: allow to set and reset rounding control
Chris@16:  */
Chris@16: 
Chris@16: namespace detail {
Chris@16: 
Chris@16: template<class Rounding>
Chris@16: struct save_state_unprotected: Rounding
Chris@16: {
Chris@16:   typedef save_state_unprotected<Rounding> unprotected_rounding;
Chris@16: };
Chris@16: 
Chris@16: } // namespace detail
Chris@16: 
Chris@16: template<class Rounding>
Chris@16: struct save_state: Rounding
Chris@16: {
Chris@16:   typename Rounding::rounding_mode mode;
Chris@16:   save_state() {
Chris@16:     this->get_rounding_mode(mode);
Chris@16:     this->init();
Chris@16:   }
Chris@16:   ~save_state() { this->set_rounding_mode(mode); }
Chris@16:   typedef detail::save_state_unprotected<Rounding> unprotected_rounding;
Chris@16: };
Chris@16:   
Chris@16: template<class Rounding>
Chris@16: struct save_state_nothing: Rounding
Chris@16: {
Chris@16:   typedef save_state_nothing<Rounding> unprotected_rounding;
Chris@16: };
Chris@16:   
Chris@16: template<class T>
Chris@16: struct rounded_math: save_state_nothing<rounded_arith_exact<T> >
Chris@16: {};
Chris@16: 
Chris@16: } // namespace interval_lib
Chris@16: } // namespace numeric
Chris@16: } // namespace boost
Chris@16: 
Chris@16: #endif // BOOST_NUMERIC_INTERVAL_ROUNDING_HPP