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

   1 // -*- C++ -*-
   2
   3 // Copyright (C) 2005-2014 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/standard_policies.hpp
  38  * Contains standard policies for containers.
  39  */
  40
  41 #ifndef PB_DS_STANDARD_POLICIES_HPP
  42 #define PB_DS_STANDARD_POLICIES_HPP
  43
  44 #include <memory>
  45 #include <ext/pb_ds/hash_policy.hpp>
  46 #include <ext/pb_ds/list_update_policy.hpp>
  47 #include <ext/pb_ds/detail/branch_policy/null_node_metadata.hpp>
  48 #include <ext/pb_ds/tree_policy.hpp>
  49 #include <ext/pb_ds/trie_policy.hpp>
  50 #include <ext/pb_ds/tag_and_trait.hpp>
  51 #include <tr1/functional>
  52
  53 namespace __gnu_pbds
  54 {
  55   namespace detail
  56   {
  57     /// Primary template, default_hash_fn.
  58     template<typename Key>
  59     struct default_hash_fn
  60     {
  61         /// Dispatched type.
  62       typedef std::tr1::hash<Key>                               type;
  63     };
  64
  65     /// Primary template, default_eq_fn.
  66     template<typename Key>
  67     struct default_eq_fn
  68     {
  69         /// Dispatched type.
  70       typedef std::equal_to<Key>                                type;
  71     };
  72
  73     /// Enumeration for default behavior of stored hash data.
  74     enum
  75       {
  76         default_store_hash = false
  77       };
  78
  79     /// Primary template, default_comb_hash_fn.
  80     struct default_comb_hash_fn
  81     {
  82         /// Dispatched type.
  83       typedef direct_mask_range_hashing<>                       type;
  84     };
  85
  86     /// Primary template, default_resize_policy.
  87     template<typename Comb_Hash_Fn>
  88     struct default_resize_policy
  89     {
  90     private:
  91       typedef typename Comb_Hash_Fn::size_type                  size_type;
  92
  93       typedef direct_mask_range_hashing<size_type>              default_fn;
  94       typedef is_same<default_fn, Comb_Hash_Fn>                 same_type;
  95       typedef hash_exponential_size_policy<size_type>           iftrue;
  96       typedef hash_prime_size_policy                            iffalse;
  97       typedef __conditional_type<same_type::value, iftrue, iffalse> cond_type;
  98       typedef typename cond_type::__type                       size_policy_type;
  99
 100       typedef hash_load_check_resize_trigger<false, size_type>  trigger;
 101
 102     public:
 103         /// Dispatched type.
 104       typedef hash_standard_resize_policy<size_policy_type, trigger,
 105                                           false, size_type>     type;
 106     };
 107
 108     /// Default update policy.
 109     struct default_update_policy
 110     {
 111         /// Dispatched type.
 112       typedef lu_move_to_front_policy<>                         type;
 113     };
 114
 115     /// Primary template, default_probe_fn.
 116     template<typename Comb_Probe_Fn>
 117     struct default_probe_fn
 118     {
 119     private:
 120       typedef typename Comb_Probe_Fn::size_type                 size_type;
 121       typedef direct_mask_range_hashing<size_type>              default_fn;
 122       typedef is_same<default_fn, Comb_Probe_Fn>                same_type;
 123       typedef linear_probe_fn<size_type>                        iftrue;
 124       typedef quadratic_probe_fn<size_type>                     iffalse;
 125       typedef __conditional_type<same_type::value, iftrue, iffalse> cond_type;
 126
 127     public:
 128         /// Dispatched type.
 129       typedef typename cond_type::__type                        type;
 130     };
 131
 132
 133     /// Primary template, default_trie_access_traits.
 134     template<typename Key>
 135       struct default_trie_access_traits;
 136
 137 #define __dtrie_alloc std::allocator<char>
 138 #define __dtrie_string std::basic_string<Char, Char_Traits, __dtrie_alloc>
 139
 140     /// Partial specialization, default_trie_access_traits.
 141     template<typename Char, typename Char_Traits>
 142       struct default_trie_access_traits<__dtrie_string>
 143       {
 144       private:
 145         typedef __dtrie_string                                  string_type;
 146
 147       public:
 148         /// Dispatched type.
 149         typedef trie_string_access_traits<string_type>          type;
 150       };
 151
 152 #undef __dtrie_alloc
 153 #undef __dtrie_string
 154
 155   } // namespace detail
 156 } // namespace __gnu_pbds
 157
 158 #endif // #ifndef PB_DS_STANDARD_POLICIES_HPP