boost_has_hash.ipp

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//  (C) Copyright John Maddock 2001. 
//  Use, modification and distribution are subject to the 
//  Boost Software License, Version 1.0. (See accompanying file 
//  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

//  See http://www.boost.org/libs/config for most recent version.

//  MACRO:         BOOST_HAS_HASH
//  TITLE:         <hashset> and <hashmap>
//  DESCRIPTION:   The C++ implementation provides the (SGI) hash_set
//                 or hash_map classes.

#if defined(__GLIBCXX__) || (defined(__GLIBCPP__) && __GLIBCPP__>=20020514) // GCC >= 3.1.0
#  define BOOST_STD_EXTENSION_NAMESPACE __gnu_cxx
#include <ext/hash_set>
#include <ext/hash_map>
#else
#include <hash_set>
#include <hash_map>
#endif

#ifndef BOOST_STD_EXTENSION_NAMESPACE
#define BOOST_STD_EXTENSION_NAMESPACE std
#endif

namespace boost_has_hash{

template <class Key, class Eq, class Hash, class Alloc>
void foo(const BOOST_STD_EXTENSION_NAMESPACE::hash_set<Key,Eq,Hash,Alloc>& )
{
}

template <class Key, class T, class Eq, class Hash, class Alloc>
void foo(const BOOST_STD_EXTENSION_NAMESPACE::hash_map<Key,T,Eq,Hash,Alloc>& )
{
}

int test()
{
   BOOST_STD_EXTENSION_NAMESPACE::hash_set<int> hs;
   foo(hs);
   BOOST_STD_EXTENSION_NAMESPACE::hash_map<int, long> hm;
   foo(hm);
   return 0;
}

}