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

   1 // -*- C++ -*-
   2
   3 // Copyright (C) 2005, 2006, 2007, 2009, 2011 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     /// default_hash_fn
  58     template<typename Key>
  59     struct default_hash_fn
  60     {
  61       typedef std::tr1::hash<Key> type;
  62     };
  63
  64     /// default_eq_fn
  65     template<typename Key>
  66     struct default_eq_fn
  67     {
  68       typedef std::equal_to<Key> type;
  69     };
  70
  71     enum
  72       {
  73         default_store_hash = false
  74       };
  75
  76     /// default_comb_hash_fn
  77     struct default_comb_hash_fn
  78     {
  79       typedef __gnu_pbds::direct_mask_range_hashing<> type;
  80     };
  81
  82     /// default_resize_policy
  83     template<typename Comb_Hash_Fn>
  84     struct default_resize_policy
  85     {
  86     private:
  87       typedef typename Comb_Hash_Fn::size_type size_type;
  88
  89       typedef __gnu_pbds::direct_mask_range_hashing<size_type> default_fn;
  90       typedef is_same<default_fn, Comb_Hash_Fn> same_type;
  91       typedef __gnu_pbds::hash_exponential_size_policy<size_type> iftrue;
  92       typedef __gnu_pbds::hash_prime_size_policy iffalse;
  93       typedef __conditional_type<same_type::value, iftrue, iffalse> cond_type;
  94       typedef typename cond_type::__type size_policy_type;
  95
  96       typedef __gnu_pbds::hash_load_check_resize_trigger<false, size_type> trigger;
  97
  98     public:
  99       typedef __gnu_pbds::hash_standard_resize_policy<size_policy_type, trigger, false, size_type> type;
 100     };
 101
 102     /// default_update_policy
 103     struct default_update_policy
 104     {
 105       typedef __gnu_pbds::lu_move_to_front_policy<> type;
 106     };
 107
 108     /// default_probe_fn
 109     template<typename Comb_Probe_Fn>
 110     struct default_probe_fn
 111     {
 112     private:
 113       typedef typename Comb_Probe_Fn::size_type size_type;
 114
 115       typedef __gnu_pbds::direct_mask_range_hashing<size_type> default_fn;
 116       typedef is_same<default_fn, Comb_Probe_Fn> same_type;
 117       typedef __gnu_pbds::linear_probe_fn<size_type> iftrue;
 118       typedef __gnu_pbds::quadratic_probe_fn<size_type> iffalse;
 119       typedef __conditional_type<same_type::value, iftrue, iffalse> cond_type;
 120
 121     public:
 122       typedef typename cond_type::__type type;
 123     };
 124
 125     /// default_trie_access_traits
 126     template<typename Key>
 127     struct default_trie_access_traits;
 128
 129     template<typename Char, typename Char_Traits>
 130     struct default_trie_access_traits<std::basic_string<Char, Char_Traits, std::allocator<char> > >
 131     {
 132     private:
 133       typedef std::basic_string<Char, Char_Traits, std::allocator<char> > string_type;
 134
 135     public:
 136       typedef __gnu_pbds::trie_string_access_traits<string_type> type;
 137     };
 138
 139   } // namespace detail
 140 } // namespace __gnu_pbds
 141
 142 #endif // #ifndef PB_DS_STANDARD_POLICIES_HPP