libstdc++
type_utils.hpp
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2 
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25 // Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
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35 
36 /**
37  * @file detail/type_utils.hpp
38  * Contains utilities for handnling 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)>)> UNIQUE##__static_assert_type
156 
157 #endif
158 
159  template<typename Type>
160  struct type_to_type
161  {
162  typedef Type type;
163  };
164  } // namespace detail
165 } // namespace __gnu_pbds
166 
167 #endif
integral_constant< bool, false > false_type
The type used as a compile-time boolean with false value.
Definition: type_traits:78
ISO C++ entities toplevel namespace is std.
integral_constant< bool, true > true_type
The type used as a compile-time boolean with true value.
Definition: type_traits:75
GNU extensions for policy-based data structures for public use.