#ifndef OPAQUE_HASH_HPP
#define OPAQUE_HASH_HPP
//
// Copyright (c) 2016
// Kyle Markley.  All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice,
//    this list of conditions and the following disclaimer.
// 2. Redistributions in binary form must reproduce the above copyright notice,
//    this list of conditions and the following disclaimer in the documentation
//    and/or other materials provided with the distribution.
// 3. Neither the name of the author nor the names of any contributors may be
//    used to endorse or promote products derived from this software without
//    specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
//
#include "data.hpp"
#include <functional>

/// \addtogroup miscellaneous
/// @{

///
/// Create a std::hash specialization for an opaque typedef
///
/// This macro must be used outside any namespace, because it creates a
/// specialization in std.
///
#define OPAQUE_HASHABLE(name) \
namespace std {\
  template <> struct hash<name> {\
    using argument_type = typename name::opaque_type;\
    using result_type = size_t;\
    result_type operator()(const argument_type& key) const {\
      return std::hash<typename name::underlying_type>{}(key.value);\
    }\
  };\
}

/// @}

#endif