ceph/src/boost/libs/multiprecision/include/boost/multiprecision/detail/min_max.hpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 //  Copyright 2016 John Maddock. Distributed under the Boost
   3 //  Software License, Version 1.0. (See accompanying file
   4 //  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   5
   6 #ifndef BOOST_MP_MIN_MAX_HPP
   7 #define BOOST_MP_MIN_MAX_HPP
   8
   9 #include <boost/multiprecision/traits/is_backend.hpp>
  10
  11 namespace boost{ namespace multiprecision{
  12
  13 //
  14 // Expression template overloads for (min) and (max):
  15 //
  16 // Introduced in response to https://svn.boost.org/trac/boost/ticket/11149
  17 // note that these can not legally be injected into namespace std, and that doing so
  18 // may break future enhancements to the standard.  None the less adding
  19 // namespace std{ using boost::multiprecision::(min); using boost::multiprecision::(max); }
  20 // to your code may get some generic code working that wouldn't work otherwise.
  21 //
  22 // The use of enable_if on the return type is to avoid poisoning std::min/max,
  23 // otherwise attempting to make an explicit call to min<long>(a, b) when these and std
  24 // versions are in scope, will cause the compiler to try to instantiate the signatures
  25 // for our versions as well as the std ones, which in turn instantiates number<long>
  26 // which fails to compile as "long" is not a valid backend type.
  27 //
  28 template <class Backend>
  29 inline typename boost::enable_if_c < boost::multiprecision::detail::is_backend<Backend>::value, const number<Backend, et_on>&>::type
  30    (min)(const number<Backend, et_on>& a, const number<Backend, et_on>& b)
  31 {
  32    return a < b ? a : b;
  33 }
  34 template <class Backend, class tag, class A1, class A2, class A3, class A4>
  35 inline typename boost::enable_if_c < boost::multiprecision::detail::is_backend<Backend>::value, const number<Backend, et_on> >::type
  36    (min)(const number<Backend, et_on>& a, const detail::expression<tag, A1, A2, A3, A4>& b)
  37 {
  38    number<Backend, et_on> t(b);
  39    if(a < t)
  40       return a;
  41    return BOOST_MP_MOVE(t);
  42 }
  43 template <class tag, class A1, class A2, class A3, class A4, class Backend>
  44 inline typename boost::enable_if_c < boost::multiprecision::detail::is_backend<Backend>::value, const number<Backend, et_on> >::type
  45    (min)(const detail::expression<tag, A1, A2, A3, A4>& a, const number<Backend, et_on>& b)
  46 {
  47    number<Backend, et_on> t(a);
  48    if(t < b)
  49       return BOOST_MP_MOVE(t);
  50    return b;
  51 }
  52 template <class tag, class A1, class A2, class A3, class A4, class tagb, class A1b, class A2b, class A3b, class A4b>
  53 inline typename detail::expression<tag, A1, A2, A3, A4>::result_type
  54       (min)(const detail::expression<tag, A1, A2, A3, A4>& a, const detail::expression<tagb, A1b, A2b, A3b, A4b>& b)
  55 {
  56    typename detail::expression<tag, A1, A2, A3, A4>::result_type t1(a), t2(b);
  57    if(t1 < t2)
  58       return BOOST_MP_MOVE(t1);
  59    return BOOST_MP_MOVE(t2);
  60 }
  61 template <class tag, class A1, class A2, class A3, class A4>
  62 inline typename detail::expression<tag, A1, A2, A3, A4>::result_type (min)(const detail::expression<tag, A1, A2, A3, A4>& a, const detail::expression<tag, A1, A2, A3, A4>& b)
  63 {
  64    typename detail::expression<tag, A1, A2, A3, A4>::result_type t1(a), t2(b);
  65    if(t1 < t2)
  66       return BOOST_MP_MOVE(t1);
  67    return BOOST_MP_MOVE(t2);
  68 }
  69
  70 template <class Backend>
  71 inline typename boost::enable_if_c < boost::multiprecision::detail::is_backend<Backend>::value, const number<Backend, et_on>&>::type
  72    (max)(const number<Backend, et_on>& a, const number<Backend, et_on>& b)
  73 {
  74    return a > b ? a : b;
  75 }
  76 template <class Backend, class tag, class A1, class A2, class A3, class A4>
  77 inline typename boost::enable_if_c < boost::multiprecision::detail::is_backend<Backend>::value, const number<Backend, et_on> >::type
  78    (max)(const number<Backend, et_on>& a, const detail::expression<tag, A1, A2, A3, A4>& b)
  79 {
  80    number<Backend, et_on> t(b);
  81    if(a > t)
  82       return a;
  83    return BOOST_MP_MOVE(t);
  84 }
  85 template <class tag, class A1, class A2, class A3, class A4, class Backend>
  86 inline typename boost::enable_if_c < boost::multiprecision::detail::is_backend<Backend>::value, const number<Backend, et_on> >::type
  87    (max)(const detail::expression<tag, A1, A2, A3, A4>& a, const number<Backend, et_on>& b)
  88 {
  89    number<Backend, et_on> t(a);
  90    if(t > b)
  91       return BOOST_MP_MOVE(t);
  92    return b;
  93 }
  94 template <class tag, class A1, class A2, class A3, class A4, class tagb, class A1b, class A2b, class A3b, class A4b>
  95 inline typename detail::expression<tag, A1, A2, A3, A4>::result_type
  96       (max)(const detail::expression<tag, A1, A2, A3, A4>& a, const detail::expression<tagb, A1b, A2b, A3b, A4b>& b)
  97 {
  98    typename detail::expression<tag, A1, A2, A3, A4>::result_type t1(a), t2(b);
  99    if(t1 > t2)
 100       return BOOST_MP_MOVE(t1);
 101    return BOOST_MP_MOVE(t2);
 102 }
 103 template <class tag, class A1, class A2, class A3, class A4>
 104 inline typename detail::expression<tag, A1, A2, A3, A4>::result_type (max)(const detail::expression<tag, A1, A2, A3, A4>& a, const detail::expression<tag, A1, A2, A3, A4>& b)
 105 {
 106    typename detail::expression<tag, A1, A2, A3, A4>::result_type t1(a), t2(b);
 107    if(t1 > t2)
 108       return BOOST_MP_MOVE(t1);
 109    return BOOST_MP_MOVE(t2);
 110 }
 111
 112 }} // namespaces
 113
 114 #endif