src/util/hash.h

   1 /*********************                                                        */
   2 /*! \file hash.h
   3  ** \verbatim
   4  ** Original author: cconway
   5  ** Major contributors: mdeters
   6  ** Minor contributors (to current version): taking
   7  ** This file is part of the CVC4 prototype.
   8  ** Copyright (c) 2009-2012  New York University and The University of Iowa
   9  ** See the file COPYING in the top-level source directory for licensing
  10  ** information.\endverbatim
  11  **
  12  ** \brief [[ Add one-line brief description here ]]
  13  **
  14  ** [[ Add lengthier description here ]]
  15  ** \todo document this file
  16  **/
  17
  18 #include "cvc4_public.h"
  19
  20 #ifndef __CVC4__HASH_H
  21 #define __CVC4__HASH_H
  22
  23 // in case it's not been declared as a namespace yet
  24 namespace __gnu_cxx {}
  25
  26 #include <ext/hash_map>
  27 #include <ext/hash_set>
  28
  29 namespace __gnu_cxx {
  30
  31 #ifdef CVC4_NEED_HASH_UINT64_T
  32 // on some versions and architectures of GNU C++, we need a
  33 // specialization of hash for 64-bit values
  34 template <>
  35 struct hash<uint64_t> {
  36   size_t operator()(uint64_t v) const {
  37     return v;
  38   }
  39 };/* struct hash<uint64_t> */
  40 #endif /* CVC4_NEED_HASH_UINT64_T */
  41
  42 }/* __gnu_cxx namespace */
  43
  44 // hackish: treat hash stuff as if it were in std namespace
  45 namespace std { using namespace __gnu_cxx; }
  46
  47 namespace CVC4 {
  48
  49 struct StringHashFunction {
  50   size_t operator()(const std::string& str) const {
  51     return std::hash<const char*>()(str.c_str());
  52   }
  53 };/* struct StringHashFunction */
  54
  55 template <class T, class U, class HashT = std::hash<T>, class HashU = std::hash<U> >
  56 struct PairHashFunction {
  57   size_t operator()(const std::pair<T, U>& pr) const {
  58     return HashT()(pr.first) ^ HashU()(pr.second);
  59   }
  60 };/* struct PairHashFunction */
  61
  62 }/* CVC4 namespace */
  63
  64 #endif /* __CVC4__HASH_H */