Chris@16: /* Boost interval/checking.hpp template implementation file
Chris@16:  *
Chris@16:  * Copyright 2002 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_CHECKING_HPP
Chris@16: #define BOOST_NUMERIC_INTERVAL_CHECKING_HPP
Chris@16: 
Chris@16: #include <stdexcept>
Chris@16: #include <string>
Chris@16: #include <cassert>
Chris@16: #include <boost/limits.hpp>
Chris@16: 
Chris@16: namespace boost {
Chris@16: namespace numeric {
Chris@16: namespace interval_lib {
Chris@16: 
Chris@16: struct exception_create_empty
Chris@16: {
Chris@16:   void operator()()
Chris@16:   {
Chris@16:     throw std::runtime_error("boost::interval: empty interval created");
Chris@16:   }
Chris@16: };
Chris@16: 
Chris@16: struct exception_invalid_number
Chris@16: {
Chris@16:   void operator()()
Chris@16:   {
Chris@16:     throw std::invalid_argument("boost::interval: invalid number");
Chris@16:   }
Chris@16: };
Chris@16: 
Chris@16: template<class T>
Chris@16: struct checking_base
Chris@16: {
Chris@16:   static T pos_inf()
Chris@16:   {
Chris@16:     assert(std::numeric_limits<T>::has_infinity);
Chris@16:     return std::numeric_limits<T>::infinity();
Chris@16:   }
Chris@16:   static T neg_inf()
Chris@16:   {
Chris@16:     assert(std::numeric_limits<T>::has_infinity);
Chris@16:     return -std::numeric_limits<T>::infinity();
Chris@16:   }
Chris@16:   static T nan()
Chris@16:   {
Chris@16:     assert(std::numeric_limits<T>::has_quiet_NaN);
Chris@16:     return std::numeric_limits<T>::quiet_NaN();
Chris@16:   }
Chris@16:   static bool is_nan(const T& x)
Chris@16:   {
Chris@16:     return std::numeric_limits<T>::has_quiet_NaN && (x != x);
Chris@16:   }
Chris@16:   static T empty_lower()
Chris@16:   {
Chris@16:     return (std::numeric_limits<T>::has_quiet_NaN ?
Chris@16:             std::numeric_limits<T>::quiet_NaN() : static_cast<T>(1));
Chris@16:   }
Chris@16:   static T empty_upper()
Chris@16:   {
Chris@16:     return (std::numeric_limits<T>::has_quiet_NaN ?
Chris@16:             std::numeric_limits<T>::quiet_NaN() : static_cast<T>(0));
Chris@16:   }
Chris@16:   static bool is_empty(const T& l, const T& u)
Chris@16:   {
Chris@16:     return !(l <= u); // safety for partial orders
Chris@16:   }
Chris@16: };
Chris@16: 
Chris@16: template<class T, class Checking = checking_base<T>,
Chris@16:          class Exception = exception_create_empty>
Chris@16: struct checking_no_empty: Checking
Chris@16: {
Chris@16:   static T nan()
Chris@16:   {
Chris@16:     assert(false);
Chris@16:     return Checking::nan();
Chris@16:   }
Chris@16:   static T empty_lower()
Chris@16:   {
Chris@16:     Exception()();
Chris@16:     return Checking::empty_lower();
Chris@16:   }
Chris@16:   static T empty_upper()
Chris@16:   {
Chris@16:     Exception()();
Chris@16:     return Checking::empty_upper();
Chris@16:   }
Chris@16:   static bool is_empty(const T&, const T&)
Chris@16:   {
Chris@16:     return false;
Chris@16:   }
Chris@16: };
Chris@16: 
Chris@16: template<class T, class Checking = checking_base<T> >
Chris@16: struct checking_no_nan: Checking
Chris@16: {
Chris@16:   static bool is_nan(const T&)
Chris@16:   {
Chris@16:     return false;
Chris@16:   }
Chris@16: };
Chris@16: 
Chris@16: template<class T, class Checking = checking_base<T>,
Chris@16:          class Exception = exception_invalid_number>
Chris@16: struct checking_catch_nan: Checking
Chris@16: {
Chris@16:   static bool is_nan(const T& x)
Chris@16:   {
Chris@16:     if (Checking::is_nan(x)) Exception()();
Chris@16:     return false;
Chris@16:   }
Chris@16: };
Chris@16: 
Chris@16: template<class T>
Chris@16: struct checking_strict:
Chris@16:   checking_no_nan<T, checking_no_empty<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_CHECKING_HPP