libstdc++-v3/include/ext/pb_ds/detail/type_utils.hpp

   1 // -*- C++ -*-
   2
   3 // Copyright (C) 2005-2024 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
   6 // software; you can redistribute it and/or modify it under the terms
   7 // of the GNU General Public License as published by the Free Software
   8 // Foundation; either version 3, or (at your option) any later
   9 // version.
  10
  11 // This library is distributed in the hope that it will be useful, but
  12 // WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 // General Public License for more details.
  15
  16 // Under Section 7 of GPL version 3, you are granted additional
  17 // permissions described in the GCC Runtime Library Exception, version
  18 // 3.1, as published by the Free Software Foundation.
  19
  20 // You should have received a copy of the GNU General Public License and
  21 // a copy of the GCC Runtime Library Exception along with this program;
  22 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  23 // <http://www.gnu.org/licenses/>.
  24
  25 // Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
  26
  27 // Permission to use, copy, modify, sell, and distribute this software
  28 // is hereby granted without fee, provided that the above copyright
  29 // notice appears in all copies, and that both that copyright notice
  30 // and this permission notice appear in supporting documentation. None
  31 // of the above authors, nor IBM Haifa Research Laboratories, make any
  32 // representation about the suitability of this software for any
  33 // purpose. It is provided "as is" without express or implied
  34 // warranty.
  35
  36 /**
  37  * @file detail/type_utils.hpp
  38  * Contains utilities for handling types. All of these classes are based on
  39  * Modern C++ by Andrei Alxandrescu.
  40  */
  41
  42 #ifndef PB_DS_TYPE_UTILS_HPP
  43 #define PB_DS_TYPE_UTILS_HPP
  44
  45 #include <cstddef>
  46 #include <utility>
  47 #include <tr1/type_traits>
  48 #include <ext/type_traits.h>
  49 #include <ext/numeric_traits.h>
  50
  51 namespace __gnu_pbds
  52 {
  53   namespace detail
  54   {
  55     using std::tr1::is_same;
  56     using std::tr1::is_const;
  57     using std::tr1::is_pointer;
  58     using std::tr1::is_reference;
  59     using std::tr1::is_fundamental;
  60     using std::tr1::is_member_object_pointer;
  61     using std::tr1::is_member_pointer;
  62     using std::tr1::is_base_of;
  63     using std::tr1::remove_const;
  64     using std::tr1::remove_reference;
  65
  66     // Need integral_const<bool, true> <-> integral_const<int, 1>, so
  67     // because of this use the following typedefs instead of importing
  68     // std::tr1's.
  69     using std::tr1::integral_constant;
  70     typedef std::tr1::integral_constant<int, 1> true_type;
  71     typedef std::tr1::integral_constant<int, 0> false_type;
  72
  73     using __gnu_cxx::__conditional_type;
  74     using __gnu_cxx::__numeric_traits;
  75
  76     template<typename T>
  77     struct is_const_pointer
  78     {
  79       enum
  80         {
  81           value = is_const<T>::value && is_pointer<T>::value
  82         };
  83     };
  84
  85     template<typename T>
  86     struct is_const_reference
  87     {
  88       enum
  89         {
  90           value = is_const<T>::value && is_reference<T>::value
  91         };
  92     };
  93
  94     template<typename T>
  95     struct is_simple
  96     {
  97       enum
  98         {
  99           value = is_fundamental<typename remove_const<T>::type>::value
 100           || is_pointer<typename remove_const<T>::type>::value
 101           || is_member_pointer<T>::value
 102         };
 103     };
 104
 105     template<typename T>
 106     class is_pair
 107     {
 108     private:
 109       template<typename U>
 110       struct is_pair_imp
 111       {
 112         enum
 113           {
 114             value = 0
 115           };
 116       };
 117
 118       template<typename U, typename V>
 119       struct is_pair_imp<std::pair<U,V> >
 120       {
 121         enum
 122           {
 123             value = 1
 124           };
 125       };
 126
 127     public:
 128       enum
 129         {
 130           value = is_pair_imp<T>::value
 131         };
 132     };
 133
 134     // Use C++11's static_assert if possible.
 135 #if __cplusplus >= 201103L
 136 #define PB_DS_STATIC_ASSERT(UNIQUE, E)  static_assert(E, #UNIQUE)
 137 #else
 138     template<bool>
 139     struct __static_assert;
 140
 141     template<>
 142     struct __static_assert<true>
 143     { };
 144
 145     template<int>
 146     struct __static_assert_dumclass
 147     {
 148       enum
 149         {
 150           v = 1
 151         };
 152     };
 153
 154 #define PB_DS_STATIC_ASSERT(UNIQUE, E)  \
 155     typedef __gnu_pbds::detail::__static_assert_dumclass<sizeof(__gnu_pbds::detail::__static_assert<bool(E)>)> \
 156       UNIQUE##__static_assert_type __attribute__((__unused__))
 157
 158 #endif
 159
 160     template<typename Type>
 161     struct type_to_type
 162     {
 163       typedef Type type;
 164     };
 165   } // namespace detail
 166 } // namespace __gnu_pbds
 167
 168 #endif