How to easily map c++ enums to strings

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If you want the enum names themselves as strings, see this post.
Otherwise, a std::map<MyEnum, char const*> will work nicely. (No point in copying your string literals to std::strings in the map)

For extra syntactic sugar, here’s how to write a map_init class. The goal is to allow

std::map<MyEnum, const char*> MyMap;
map_init(MyMap)
    (eValue1, "A")
    (eValue2, "B")
    (eValue3, "C")
;

The function template <typename T> map_init(T&) returns a map_init_helper<T>.
map_init_helper<T> stores a T&, and defines the trivial map_init_helper& operator()(typename T::key_type const&, typename T::value_type const&). (Returning *this from operator() allows the chaining of operator(), like operator<< on std::ostreams)

template<typename T> struct map_init_helper
{
    T& data;
    map_init_helper(T& d) : data(d) {}
    map_init_helper& operator() (typename T::key_type const& key, typename T::mapped_type const& value)
    {
        data[key] = value;
        return *this;
    }
};

template<typename T> map_init_helper<T> map_init(T& item)
{
    return map_init_helper<T>(item);
}

Since the function and helper class are templated, you can use them for any map, or map-like structure. I.e. it can also add entries to std::unordered_map

If you don’t like writing these helpers, boost::assign offers the same functionality out of the box.

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