libcxx/include/__cxx03/__algorithm/minmax.h

   1 //===----------------------------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #ifndef _LIBCPP___ALGORITHM_MINMAX_H
  10 #define _LIBCPP___ALGORITHM_MINMAX_H
  11
  12 #include <__cxx03/__algorithm/comp.h>
  13 #include <__cxx03/__algorithm/minmax_element.h>
  14 #include <__cxx03/__config>
  15 #include <__cxx03/__functional/identity.h>
  16 #include <__cxx03/__type_traits/is_callable.h>
  17 #include <__cxx03/__utility/pair.h>
  18 #include <__cxx03/initializer_list>
  19
  20 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  21 #  pragma GCC system_header
  22 #endif
  23
  24 _LIBCPP_BEGIN_NAMESPACE_STD
  25
  26 template <class _Tp, class _Compare>
  27 _LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<const _Tp&, const _Tp&>
  28 minmax(_LIBCPP_LIFETIMEBOUND const _Tp& __a, _LIBCPP_LIFETIMEBOUND const _Tp& __b, _Compare __comp) {
  29   return __comp(__b, __a) ? pair<const _Tp&, const _Tp&>(__b, __a) : pair<const _Tp&, const _Tp&>(__a, __b);
  30 }
  31
  32 template <class _Tp>
  33 _LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<const _Tp&, const _Tp&>
  34 minmax(_LIBCPP_LIFETIMEBOUND const _Tp& __a, _LIBCPP_LIFETIMEBOUND const _Tp& __b) {
  35   return std::minmax(__a, __b, __less<>());
  36 }
  37
  38 #ifndef _LIBCPP_CXX03_LANG
  39
  40 template <class _Tp, class _Compare>
  41 _LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_Tp, _Tp>
  42 minmax(initializer_list<_Tp> __t, _Compare __comp) {
  43   static_assert(__is_callable<_Compare, _Tp, _Tp>::value, "The comparator has to be callable");
  44   __identity __proj;
  45   auto __ret = std::__minmax_element_impl(__t.begin(), __t.end(), __comp, __proj);
  46   return pair<_Tp, _Tp>(*__ret.first, *__ret.second);
  47 }
  48
  49 template <class _Tp>
  50 _LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pair<_Tp, _Tp>
  51 minmax(initializer_list<_Tp> __t) {
  52   return std::minmax(__t, __less<>());
  53 }
  54
  55 #endif // _LIBCPP_CXX03_LANG
  56
  57 _LIBCPP_END_NAMESPACE_STD
  58
  59 #endif // _LIBCPP___ALGORITHM_MINMAX_H