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// boost integer.hpp header file -------------------------------------------//
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// Copyright Beman Dawes and Daryle Walker 1999. Distributed under the Boost
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// Software License, Version 1.0. (See accompanying file
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// LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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// See http://www.boost.org/libs/integer for documentation.
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// 22 Sep 01 Added value-based integer templates. (Daryle Walker)
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// 01 Apr 01 Modified to use new <boost/limits.hpp> header. (John Maddock)
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// 30 Jul 00 Add typename syntax fix (Jens Maurer)
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// 28 Aug 99 Initial version
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#ifndef BOOST_INTEGER_HPP
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#define BOOST_INTEGER_HPP
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#include <boost/integer_fwd.hpp> // self include
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#include <boost/integer_traits.hpp> // for boost::integer_traits
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#include <boost/limits.hpp> // for std::numeric_limits
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// Helper templates ------------------------------------------------------//
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// fast integers from least integers
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// int_fast_t<> works correctly for unsigned too, in spite of the name.
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template< typename LeastInt >
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struct int_fast_t { typedef LeastInt fast; }; // imps may specialize
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// convert category to type
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template< int Category > struct int_least_helper {}; // default is empty
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// specializatons: 1=long, 2=int, 3=short, 4=signed char,
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// 6=unsigned long, 7=unsigned int, 8=unsigned short, 9=unsigned char
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// no specializations for 0 and 5: requests for a type > long are in error
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template<> struct int_least_helper<1> { typedef long least; };
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template<> struct int_least_helper<2> { typedef int least; };
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template<> struct int_least_helper<3> { typedef short least; };
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template<> struct int_least_helper<4> { typedef signed char least; };
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template<> struct int_least_helper<6> { typedef unsigned long least; };
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template<> struct int_least_helper<7> { typedef unsigned int least; };
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template<> struct int_least_helper<8> { typedef unsigned short least; };
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template<> struct int_least_helper<9> { typedef unsigned char least; };
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// integer templates specifying number of bits ---------------------------//
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template< int Bits > // bits (including sign) required
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typedef typename int_least_helper
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(Bits-1 <= std::numeric_limits<long>::digits) +
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(Bits-1 <= std::numeric_limits<int>::digits) +
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(Bits-1 <= std::numeric_limits<short>::digits) +
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(Bits-1 <= std::numeric_limits<signed char>::digits)
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typedef typename int_fast_t<least>::fast fast;
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template< int Bits > // bits required
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typedef typename int_least_helper
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(Bits <= std::numeric_limits<unsigned long>::digits) +
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(Bits <= std::numeric_limits<unsigned int>::digits) +
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(Bits <= std::numeric_limits<unsigned short>::digits) +
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(Bits <= std::numeric_limits<unsigned char>::digits)
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typedef typename int_fast_t<least>::fast fast;
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// int_fast_t<> works correctly for unsigned too, in spite of the name.
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// integer templates specifying extreme value ----------------------------//
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template< long MaxValue > // maximum value to require support
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struct int_max_value_t
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typedef typename int_least_helper
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(MaxValue <= integer_traits<long>::const_max) +
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(MaxValue <= integer_traits<int>::const_max) +
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(MaxValue <= integer_traits<short>::const_max) +
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(MaxValue <= integer_traits<signed char>::const_max)
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typedef typename int_fast_t<least>::fast fast;
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template< long MinValue > // minimum value to require support
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struct int_min_value_t
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typedef typename int_least_helper
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(MinValue >= integer_traits<long>::const_min) +
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(MinValue >= integer_traits<int>::const_min) +
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(MinValue >= integer_traits<short>::const_min) +
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(MinValue >= integer_traits<signed char>::const_min)
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typedef typename int_fast_t<least>::fast fast;
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template< unsigned long Value > // maximum value to require support
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typedef typename int_least_helper
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(Value <= integer_traits<unsigned long>::const_max) +
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(Value <= integer_traits<unsigned int>::const_max) +
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(Value <= integer_traits<unsigned short>::const_max) +
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(Value <= integer_traits<unsigned char>::const_max)
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typedef typename int_fast_t<least>::fast fast;
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#endif // BOOST_INTEGER_HPP