tuple_hash.h

#pragma once
namespace std{

namespace {

template <class Tuple, size_t Index = std::tuple_size<Tuple>::value - 1>
struct HashValueImpl {
    static void apply(size_t& seed, Tuple const& tuple) {
        HashValueImpl<Tuple, Index-1>::apply(seed, tuple);
        boost::hash_combine(seed, std::get<Index>(tuple));
    }
};

template <class Tuple>
struct HashValueImpl<Tuple, 0> {
    static void apply(size_t& seed, Tuple const& tuple) {
        boost::hash_combine(seed, std::get<0>(tuple));
    }
};

}

template <typename ... TT>
struct hash<const std::tuple<TT...>> {
    size_t operator()(std::tuple<TT...> const& tt) const {
        size_t seed = 0;
        HashValueImpl<std::tuple<TT...> >::apply(seed, tt);
        return seed;
    }
};

}