wtf/HashIterators.h

   1 // -*- mode: c++; c-basic-offset: 4 -*-
   2 /*
   3  * Copyright (C) 2007 Apple Inc.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
  15  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  17  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
  18  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  19  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  20  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  21  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  22  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  24  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  25  */
  26
  27 #ifndef WTF_HashIterators_h
  28 #define WTF_HashIterators_h
  29
  30 namespace WTF {
  31
  32     template<typename HashTableType, typename KeyType, typename MappedType> struct HashTableConstKeysIterator;
  33     template<typename HashTableType, typename KeyType, typename MappedType> struct HashTableConstValuesIterator;
  34     template<typename HashTableType, typename KeyType, typename MappedType> struct HashTableKeysIterator;
  35     template<typename HashTableType, typename KeyType, typename MappedType> struct HashTableValuesIterator;
  36
  37     template<typename HashTableType, typename KeyType, typename MappedType> struct HashTableConstIteratorAdapter<HashTableType, std::pair<KeyType, MappedType> > {
  38     private:
  39         typedef std::pair<KeyType, MappedType> ValueType;
  40     public:
  41         typedef HashTableConstKeysIterator<HashTableType, KeyType, MappedType> Keys;
  42         typedef HashTableConstValuesIterator<HashTableType, KeyType, MappedType> Values;
  43
  44         HashTableConstIteratorAdapter(const typename HashTableType::const_iterator& impl) : m_impl(impl) {}
  45
  46         const ValueType* get() const { return (const ValueType*)m_impl.get(); }
  47         const ValueType& operator*() const { return *get(); }
  48         const ValueType* operator->() const { return get(); }
  49
  50         HashTableConstIteratorAdapter& operator++() { ++m_impl; return *this; }
  51         // postfix ++ intentionally omitted
  52
  53         Keys keys() { return Keys(*this); }
  54         Values values() { return Values(*this); }
  55
  56         typename HashTableType::const_iterator m_impl;
  57     };
  58
  59     template<typename HashTableType, typename KeyType, typename MappedType> struct HashTableIteratorAdapter<HashTableType, std::pair<KeyType, MappedType> > {
  60     private:
  61         typedef std::pair<KeyType, MappedType> ValueType;
  62     public:
  63         typedef HashTableKeysIterator<HashTableType, KeyType, MappedType> Keys;
  64         typedef HashTableValuesIterator<HashTableType, KeyType, MappedType> Values;
  65
  66         HashTableIteratorAdapter(const typename HashTableType::iterator& impl) : m_impl(impl) {}
  67
  68         ValueType* get() const { return (ValueType*)m_impl.get(); }
  69         ValueType& operator*() const { return *get(); }
  70         ValueType* operator->() const { return get(); }
  71
  72         HashTableIteratorAdapter& operator++() { ++m_impl; return *this; }
  73         // postfix ++ intentionally omitted
  74
  75         operator HashTableConstIteratorAdapter<HashTableType, ValueType>() {
  76             typename HashTableType::const_iterator i = m_impl;
  77             return i;
  78         }
  79
  80         Keys keys() { return Keys(*this); }
  81         Values values() { return Values(*this); }
  82
  83         typename HashTableType::iterator m_impl;
  84     };
  85
  86     template<typename HashTableType, typename KeyType, typename MappedType> struct HashTableConstKeysIterator {
  87     private:
  88         typedef HashTableConstIteratorAdapter<HashTableType, std::pair<KeyType, MappedType> > ConstIterator;
  89
  90     public:
  91         HashTableConstKeysIterator(const ConstIterator& impl) : m_impl(impl) {}
  92
  93         const KeyType* get() const { return &(m_impl.get()->first); }
  94         const KeyType& operator*() const { return *get(); }
  95         const KeyType* operator->() const { return get(); }
  96
  97         HashTableConstKeysIterator& operator++() { ++m_impl; return *this; }
  98         // postfix ++ intentionally omitted
  99
 100         ConstIterator m_impl;
 101     };
 102
 103     template<typename HashTableType, typename KeyType, typename MappedType> struct HashTableConstValuesIterator {
 104     private:
 105         typedef HashTableConstIteratorAdapter<HashTableType, std::pair<KeyType, MappedType> > ConstIterator;
 106
 107     public:
 108         HashTableConstValuesIterator(const ConstIterator& impl) : m_impl(impl) {}
 109
 110         const MappedType* get() const { return &(m_impl.get()->second); }
 111         const MappedType& operator*() const { return *get(); }
 112         const MappedType* operator->() const { return get(); }
 113
 114         HashTableConstValuesIterator& operator++() { ++m_impl; return *this; }
 115         // postfix ++ intentionally omitted
 116
 117         ConstIterator m_impl;
 118     };
 119
 120     template<typename HashTableType, typename KeyType, typename MappedType> struct HashTableKeysIterator {
 121     private:
 122         typedef HashTableIteratorAdapter<HashTableType, std::pair<KeyType, MappedType> > Iterator;
 123         typedef HashTableConstIteratorAdapter<HashTableType, std::pair<KeyType, MappedType> > ConstIterator;
 124
 125     public:
 126         HashTableKeysIterator(const Iterator& impl) : m_impl(impl) {}
 127
 128         KeyType* get() const { return &(m_impl.get()->first); }
 129         KeyType& operator*() const { return *get(); }
 130         KeyType* operator->() const { return get(); }
 131
 132         HashTableKeysIterator& operator++() { ++m_impl; return *this; }
 133         // postfix ++ intentionally omitted
 134
 135         operator HashTableConstKeysIterator<HashTableType, KeyType, MappedType>() {
 136             ConstIterator i = m_impl;
 137             return i;
 138         }
 139
 140         Iterator m_impl;
 141     };
 142
 143     template<typename HashTableType, typename KeyType, typename MappedType> struct HashTableValuesIterator {
 144     private:
 145         typedef HashTableIteratorAdapter<HashTableType, std::pair<KeyType, MappedType> > Iterator;
 146         typedef HashTableConstIteratorAdapter<HashTableType, std::pair<KeyType, MappedType> > ConstIterator;
 147
 148     public:
 149         HashTableValuesIterator(const Iterator& impl) : m_impl(impl) {}
 150
 151         MappedType* get() const { return &(m_impl.get()->second); }
 152         MappedType& operator*() const { return *get(); }
 153         MappedType* operator->() const { return get(); }
 154
 155         HashTableValuesIterator& operator++() { ++m_impl; return *this; }
 156         // postfix ++ intentionally omitted
 157
 158         operator HashTableConstValuesIterator<HashTableType, KeyType, MappedType>() {
 159             ConstIterator i = m_impl;
 160             return i;
 161         }
 162
 163         Iterator m_impl;
 164     };
 165
 166     template<typename T, typename U, typename V>
 167         inline bool operator==(const HashTableConstKeysIterator<T, U, V>& a, const HashTableConstKeysIterator<T, U, V>& b)
 168     {
 169         return a.m_impl == b.m_impl;
 170     }
 171
 172     template<typename T, typename U, typename V>
 173         inline bool operator!=(const HashTableConstKeysIterator<T, U, V>& a, const HashTableConstKeysIterator<T, U, V>& b)
 174     {
 175         return a.m_impl != b.m_impl;
 176     }
 177
 178     template<typename T, typename U, typename V>
 179         inline bool operator==(const HashTableConstValuesIterator<T, U, V>& a, const HashTableConstValuesIterator<T, U, V>& b)
 180     {
 181         return a.m_impl == b.m_impl;
 182     }
 183
 184     template<typename T, typename U, typename V>
 185         inline bool operator!=(const HashTableConstValuesIterator<T, U, V>& a, const HashTableConstValuesIterator<T, U, V>& b)
 186     {
 187         return a.m_impl != b.m_impl;
 188     }
 189
 190     template<typename T, typename U, typename V>
 191         inline bool operator==(const HashTableKeysIterator<T, U, V>& a, const HashTableKeysIterator<T, U, V>& b)
 192     {
 193         return a.m_impl == b.m_impl;
 194     }
 195
 196     template<typename T, typename U, typename V>
 197         inline bool operator!=(const HashTableKeysIterator<T, U, V>& a, const HashTableKeysIterator<T, U, V>& b)
 198     {
 199         return a.m_impl != b.m_impl;
 200     }
 201
 202     template<typename T, typename U, typename V>
 203         inline bool operator==(const HashTableValuesIterator<T, U, V>& a, const HashTableValuesIterator<T, U, V>& b)
 204     {
 205         return a.m_impl == b.m_impl;
 206     }
 207
 208     template<typename T, typename U, typename V>
 209         inline bool operator!=(const HashTableValuesIterator<T, U, V>& a, const HashTableValuesIterator<T, U, V>& b)
 210     {
 211         return a.m_impl != b.m_impl;
 212     }
 213
 214
 215 } // namespace WTF
 216
 217 #endif // WTF_HashIterators_h