sl@0: /* Boost interval/rounding.hpp template implementation file
sl@0:  *
sl@0:  * Copyright 2002-2003 Hervé Brönnimann, Guillaume Melquiond, Sylvain Pion
sl@0:  *
sl@0:  * Distributed under the Boost Software License, Version 1.0.
sl@0:  * (See accompanying file LICENSE_1_0.txt or
sl@0:  * copy at http://www.boost.org/LICENSE_1_0.txt)
sl@0:  */
sl@0: 
sl@0: #ifndef BOOST_NUMERIC_INTERVAL_ROUNDING_HPP
sl@0: #define BOOST_NUMERIC_INTERVAL_ROUNDING_HPP
sl@0: 
sl@0: namespace boost {
sl@0: namespace numeric {
sl@0: namespace interval_lib {
sl@0: 
sl@0: /*
sl@0:  * Default rounding_control class (does nothing)
sl@0:  */
sl@0: 
sl@0: template<class T>
sl@0: struct rounding_control
sl@0: {
sl@0:   typedef int rounding_mode;
sl@0:   static void get_rounding_mode(rounding_mode&) {}
sl@0:   static void set_rounding_mode(rounding_mode)  {}
sl@0:   static void upward()     {}
sl@0:   static void downward()   {}
sl@0:   static void to_nearest() {}
sl@0:   static const T& to_int(const T& x)         { return x; }
sl@0:   static const T& force_rounding(const T& x) { return x; }
sl@0: };
sl@0: 
sl@0: /*
sl@0:  * A few rounding control classes (exact/std/opp: see documentation)
sl@0:  *   rounded_arith_* control the rounding of the arithmetic operators
sl@0:  *   rounded_transc_* control the rounding of the transcendental functions
sl@0:  */
sl@0: 
sl@0: template<class T, class Rounding = rounding_control<T> >
sl@0: struct rounded_arith_exact;
sl@0: 
sl@0: template<class T, class Rounding = rounding_control<T> >
sl@0: struct rounded_arith_std;
sl@0: 
sl@0: template<class T, class Rounding = rounding_control<T> >
sl@0: struct rounded_arith_opp;
sl@0: 
sl@0: template<class T, class Rounding>
sl@0: struct rounded_transc_dummy;
sl@0: 
sl@0: template<class T, class Rounding = rounded_arith_exact<T> > 
sl@0: struct rounded_transc_exact;
sl@0: 
sl@0: template<class T, class Rounding = rounded_arith_std<T> > 
sl@0: struct rounded_transc_std;
sl@0: 
sl@0: template<class T, class Rounding = rounded_arith_opp<T> > 
sl@0: struct rounded_transc_opp;
sl@0: 
sl@0: /*
sl@0:  * State-saving classes: allow to set and reset rounding control
sl@0:  */
sl@0: 
sl@0: namespace detail {
sl@0: 
sl@0: template<class Rounding>
sl@0: struct save_state_unprotected: Rounding
sl@0: {
sl@0:   typedef save_state_unprotected<Rounding> unprotected_rounding;
sl@0: };
sl@0: 
sl@0: } // namespace detail
sl@0: 
sl@0: template<class Rounding>
sl@0: struct save_state: Rounding
sl@0: {
sl@0:   typename Rounding::rounding_mode mode;
sl@0:   save_state() {
sl@0:     this->get_rounding_mode(mode);
sl@0:     this->init();
sl@0:   }
sl@0:   ~save_state() { this->set_rounding_mode(mode); }
sl@0:   typedef detail::save_state_unprotected<Rounding> unprotected_rounding;
sl@0: };
sl@0:   
sl@0: template<class Rounding>
sl@0: struct save_state_nothing: Rounding
sl@0: {
sl@0:   typedef save_state_nothing<Rounding> unprotected_rounding;
sl@0: };
sl@0:   
sl@0: template<class T>
sl@0: struct rounded_math: save_state_nothing<rounded_arith_exact<T> >
sl@0: {};
sl@0: 
sl@0: } // namespace interval_lib
sl@0: } // namespace numeric
sl@0: } // namespace boost
sl@0: 
sl@0: #endif // BOOST_NUMERIC_INTERVAL_ROUNDING_HPP