JSON convert Map with Integer keys
Like @HotLicks said, when you convert objects to JSON, the key part of the JSON map will be returned as a String. I don't believe there's any way to move around this behavior. I'd also steer clear of using integers as keys in your map, if the intended behavior is as a JSON map. Instead, I'd do something like:
map.put("identifier", 1);map.put("value", "sample");It's a little bit more verbose, but it's also easier to see how that translates to JSON.
It seems like map<int,int> is not matched properly. It is possible to use a derived class - like so:
struct Int_int_map : map<int, int> { inline friend void to_json(json &j, Int_int_map const &m) { j = json(); for (auto &key_val : m) j[to_string(key_val.first)] = key_val.second; } inline friend void from_json(const json &j, Int_int_map &m) { for (auto &key_val : j.get<json::object_t>()) m[std::stoi(key_val.first)] = key_val.second; }};