| 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 std::enable_if<boost::multiprecision::detail::is_backend<Backend>::value, const number<Backend, et_on>&>::type(min)(const number<Backend, et_on>& a, const number<Backend, et_on>& b) |
| 30 | { |
| 31 | return a < b ? a : b; |
| 32 | } |
| 33 | template <class Backend, class tag, class A1, class A2, class A3, class A4> |
| 34 | inline typename std::enable_if<boost::multiprecision::detail::is_backend<Backend>::value, const number<Backend, et_on> >::type(min)(const number<Backend, et_on>& a, const detail::expression<tag, A1, A2, A3, A4>& b) |
| 35 | { |
| 36 | number<Backend, et_on> t(b); |
| 37 | if (a < t) |
| 38 | return a; |
| 39 | return t; |
| 40 | } |
| 41 | template <class tag, class A1, class A2, class A3, class A4, class Backend> |
| 42 | inline typename std::enable_if<boost::multiprecision::detail::is_backend<Backend>::value, const number<Backend, et_on> >::type(min)(const detail::expression<tag, A1, A2, A3, A4>& a, const number<Backend, et_on>& b) |
| 43 | { |
| 44 | number<Backend, et_on> t(a); |
| 45 | if (t < b) |
| 46 | return t; |
| 47 | return b; |
| 48 | } |
| 49 | template <class tag, class A1, class A2, class A3, class A4, class tagb, class A1b, class A2b, class A3b, class A4b> |
| 50 | inline typename detail::expression<tag, A1, A2, A3, A4>::result_type(min)(const detail::expression<tag, A1, A2, A3, A4>& a, const detail::expression<tagb, A1b, A2b, A3b, A4b>& b) |
| 51 | { |
| 52 | typename detail::expression<tag, A1, A2, A3, A4>::result_type t1(a), t2(b); |
| 53 | if (t1 < t2) |
| 54 | return t1; |
| 55 | return t2; |
| 56 | } |
| 57 | template <class tag, class A1, class A2, class A3, class A4> |
| 58 | 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) |
| 59 | { |
| 60 | typename detail::expression<tag, A1, A2, A3, A4>::result_type t1(a), t2(b); |
| 61 | if (t1 < t2) |
| 62 | return t1; |
| 63 | return t2; |
| 64 | } |
| 65 | |
| 66 | template <class Backend> |
| 67 | inline typename std::enable_if<boost::multiprecision::detail::is_backend<Backend>::value, const number<Backend, et_on>&>::type(max)(const number<Backend, et_on>& a, const number<Backend, et_on>& b) |
| 68 | { |
| 69 | return a > b ? a : b; |
| 70 | } |
| 71 | template <class Backend, class tag, class A1, class A2, class A3, class A4> |
| 72 | inline typename std::enable_if<boost::multiprecision::detail::is_backend<Backend>::value, const number<Backend, et_on> >::type(max)(const number<Backend, et_on>& a, const detail::expression<tag, A1, A2, A3, A4>& b) |
| 73 | { |
| 74 | number<Backend, et_on> t(b); |
| 75 | if (a > t) |
| 76 | return a; |
| 77 | return t; |
| 78 | } |
| 79 | template <class tag, class A1, class A2, class A3, class A4, class Backend> |
| 80 | inline typename std::enable_if<boost::multiprecision::detail::is_backend<Backend>::value, const number<Backend, et_on> >::type(max)(const detail::expression<tag, A1, A2, A3, A4>& a, const number<Backend, et_on>& b) |
| 81 | { |
| 82 | number<Backend, et_on> t(a); |
| 83 | if (t > b) |
| 84 | return t; |
| 85 | return b; |
| 86 | } |
| 87 | template <class tag, class A1, class A2, class A3, class A4, class tagb, class A1b, class A2b, class A3b, class A4b> |
| 88 | inline typename detail::expression<tag, A1, A2, A3, A4>::result_type(max)(const detail::expression<tag, A1, A2, A3, A4>& a, const detail::expression<tagb, A1b, A2b, A3b, A4b>& b) |
| 89 | { |
| 90 | typename detail::expression<tag, A1, A2, A3, A4>::result_type t1(a), t2(b); |
| 91 | if (t1 > t2) |
| 92 | return t1; |
| 93 | return t2; |
| 94 | } |
| 95 | template <class tag, class A1, class A2, class A3, class A4> |
| 96 | 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) |
| 97 | { |
| 98 | typename detail::expression<tag, A1, A2, A3, A4>::result_type t1(a), t2(b); |
| 99 | if (t1 > t2) |
| 100 | return t1; |
| 101 | return t2; |
| 102 | } |
| 103 | |
| 104 | }} // namespace boost::multiprecision |
| 105 | |
| 106 | #endif |
| 107 | |