How to build a compile-time key/value store?

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In C++11:

template <int kk, int vv>
struct kv
{
    static const int k = kk, v = vv;
};

template <int dflt, typename...>
struct ct_map;

template <int dflt>
struct ct_map<dflt>
{
    template<int>
    struct get
    {
        static const int val = dflt;
    };
};

template<int dflt, int k, int v, typename... rest>
struct ct_map<dflt, kv<k, v>, rest...>
{
    template<int kk>
    struct get
    {
        static const int val =
            (kk == k) ?
            v :
            ct_map<dflt, rest...>::template get<kk>::val;
    };
};

typedef ct_map<42, kv<10, 20>, kv<11, 21>, kv<23, 7>> mymap;

#include <iostream>
int main()
{
    std::cout << mymap::get<10>::val << std::endl;
    std::cout << mymap::get<11>::val << std::endl;
    std::cout << mymap::get<23>::val << std::endl;
    std::cout << mymap::get<33>::val << std::endl;
}

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