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, 2010, 2011  The Analysis of Computer Systems Group (ACSys)
   9  ** Courant Institute of Mathematical Sciences
  10  ** New York University
  11  ** See the file COPYING in the top-level source directory for licensing
  12  ** information.\endverbatim
  13  **
  14  ** \brief [[ Add one-line brief description here ]]
  15  **
  16  ** [[ Add lengthier description here ]]
  17  ** \todo document this file
  18  **/
  19
  20 #include "cvc4_public.h"
  21
  22 #ifndef __CVC4__HASH_H
  23 #define __CVC4__HASH_H
  24
  25 // in case it's not been declared as a namespace yet
  26 namespace __gnu_cxx {}
  27
  28 #include <ext/hash_map>
  29 #include <ext/hash_set>
  30
  31 namespace __gnu_cxx {
  32
  33 #ifdef CVC4_NEED_HASH_UINT64_T
  34 // on some versions and architectures of GNU C++, we need a
  35 // specialization of hash for 64-bit values
  36 template <>
  37 struct hash<uint64_t> {
  38   size_t operator()(uint64_t v) const {
  39     return v;
  40   }
  41 };/* struct hash<uint64_t> */
  42 #endif /* CVC4_NEED_HASH_UINT64_T */
  43
  44 }/* __gnu_cxx namespace */
  45
  46 // hackish: treat hash stuff as if it were in std namespace
  47 namespace std { using namespace __gnu_cxx; }
  48
  49 namespace CVC4 {
  50
  51 struct StringHashFunction {
  52   size_t operator()(const std::string& str) const {
  53     return std::hash<const char*>()(str.c_str());
  54   }
  55 };/* struct StringHashFunction */
  56
  57 template <class T, class U, class HashT = std::hash<T>, class HashU = std::hash<U> >
  58 struct PairHashFunction {
  59   size_t operator()(const std::pair<T, U>& pr) const {
  60     return HashT()(pr.first) ^ HashU()(pr.second);
  61   }
  62 };/* struct PairHashFunction */
  63
  64 }/* CVC4 namespace */
  65
  66 #endif /* __CVC4__HASH_H */