libstdc++
types_traits.hpp
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35
36/**
37 * @file detail/types_traits.hpp
38 * Contains a traits class of types used by containers.
39 */
40
41#ifndef PB_DS_TYPES_TRAITS_HPP
42#define PB_DS_TYPES_TRAITS_HPP
43
44#include <algorithm>
45#include <utility>
48#include <memory>
49
50namespace __gnu_pbds
51{
52 namespace detail
53 {
54 /**
55 * @addtogroup traits Traits
56 * @{
57 */
58
59 /// Primary template.
60 template<typename Key, typename Mapped>
62 {
63 static const bool __simple = is_simple<Key>::value
64 && is_simple<Mapped>::value;
65 typedef integral_constant<int, __simple> indicator;
66 };
67
68 /// Specialization.
69 template<typename Key>
71 {
72 typedef integral_constant<int, is_simple<Key>::value> indicator;
73 };
74
75
76 /// Stored value.
77 template<typename _Tv>
79 {
80 typedef _Tv value_type;
81 value_type m_value;
82 };
83
84 /// Stored hash.
85 template<typename _Th>
87 {
88 typedef _Th hash_type;
89 hash_type m_hash;
90 };
91
92 /// Primary template for representation of stored data.
93 /// Two types of data can be stored: value and hash.
94 template<typename _Tv, typename _Th, bool Store_Hash>
96 : public stored_value<_Tv>, public stored_hash<_Th>
97 { };
98
99 /// Specialization for representation of stored data of just value type.
100 template<typename _Tv, typename _Th>
101 struct stored_data<_Tv, _Th, false>
102 : public stored_value<_Tv>
103 { };
104
105 /// Choose value_type to be a key/value pair or just a key.
106 template<typename Key, typename Mapped>
108 {
110 };
111
112 /// Specialization for sets where the key is the value_type.
113 template<typename Key>
115 {
116 typedef Key type;
117 };
118
119 /// Base class for conditionally defining a static data member.
120 template<typename Key, typename Mapped, typename _Alloc, bool Store_Hash>
122 { };
123
124 /// Specialization that defines a static data member of type null_type.
125 template<typename Key,typename _Alloc, bool Store_Hash>
126 struct maybe_null_type<Key, null_type, _Alloc, Store_Hash>
127 {
128 static null_type s_null_type;
129 };
130
131 template<typename Key,typename _Alloc, bool Store_Hash>
134
135 /// Consistent API for accessing allocator-related types.
136 template<typename _Alloc, typename T>
138#if __cplusplus >= 201103L
140 {
141 using reference = T&;
142 using const_reference = const T&;
143 };
144#else
145 : _Alloc::template rebind<T>::other
146 {
147 typedef typename _Alloc::template rebind<T>::other allocator_type;
148 };
149#endif
150
151
152 /// Traits for abstract types.
153 template<typename Key, typename Mapped, typename _Alloc, bool Store_Hash>
155 : public maybe_null_type<Key, Mapped, _Alloc, Store_Hash>
156 {
157 public:
158 typedef typename _Alloc::size_type size_type;
160 typedef Key key_type;
161 typedef Mapped mapped_type;
162
163 private:
167
169
170 public:
171 typedef typename __rebind_ma::pointer mapped_pointer;
172 typedef typename __rebind_ma::const_pointer mapped_const_pointer;
173 typedef typename __rebind_ma::reference mapped_reference;
174 typedef typename __rebind_ma::const_reference mapped_const_reference;
175
176 typedef typename __rebind_va::pointer pointer;
177 typedef typename __rebind_va::const_pointer const_pointer;
178 typedef typename __rebind_va::reference reference;
179 typedef typename __rebind_va::const_reference const_reference;
180
182
183 typedef typename __rebind_ka::pointer key_pointer;
184 typedef typename __rebind_ka::const_pointer key_const_pointer;
185 typedef typename __rebind_ka::reference key_reference;
186 typedef typename __rebind_ka::const_reference key_const_reference;
188 typedef integral_constant<int, Store_Hash> store_extra;
189 typedef typename __nothrowcopy::indicator no_throw_indicator;
190
191 store_extra m_store_extra_indicator;
192 no_throw_indicator m_no_throw_copies_indicator;
193 };
194 ///@}
195 } // namespace detail
196} // namespace __gnu_pbds
197
198#endif
GNU extensions for policy-based data structures for public use.
Uniform interface to all allocator types.
Struct holding two objects of arbitrary type.
Definition: stl_pair.h:189
Represents no type, or absence of type, for template tricks.
Primary template for representation of stored data. Two types of data can be stored: value and hash.
Choose value_type to be a key/value pair or just a key.
Base class for conditionally defining a static data member.
Consistent API for accessing allocator-related types.
Traits for abstract types.