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I recently stumbles across some problem with initializer lists. Consider a program that stores map-like data struct MyMapLike { MyMapLike(std::map<std::string, int> data) :data(std::move(data)) { } private: std::map<std::string, int> data; }; That looks straight forward. But when initializing it, it becomes ugly. I want to let it look like MyMapLike maps = { { "One", 1 }, { "Two", 2 } }; But the compiler doesn't want to accept this, because the above means that it should look for a two-parameter constructor that can accept { "One", 1 } and { "Two", 2 } respectively. I need to add extra braces, to make it look like a single-parameter constructor accepting the { { ... }, { ... } } MyMapLike maps = { { { "One", 1 }, { "Two", 2 } } }; I would not like to write it like that. Since I have a map-like class, and the initializer has the abstract value of a mapping-list, I would like to use the former version, and be independent of any such implementation details like level of nesting of constructors. One work around is to declare an initializer-list constructor struct MyMapLike { MyMapLike(std::initializer_list< std::map<std::string, int>::value_type > vals) :data(vals.begin(), vals.end()) { } MyMapLike(std::map<std::string, int> data) :data(std::move(data)) { } private: std::map<std::string, int> data; }; Now I can use the former, because when I have an initializer-list constructor, the whole initializer list is treated as one element instead of being splitted into elements. But I think this separate need of the constructor is dead ugly. I'm looking for guidance: What do you think about the former and latter form of initialization? Does it make sense to be required to have extra braces in this

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