1 #include <iostream> 2 #include <nlohmann/json.hpp> 3 4 using json = nlohmann::json; 5 main()6int main() 7 { 8 // create JSON values 9 json j_null; 10 json j_boolean = true; 11 json j_number_integer = 17; 12 json j_number_float = 23.42; 13 json j_object = {{"one", 1}, {"two", 2}}; 14 json j_object_empty(json::value_t::object); 15 json j_array = {1, 2, 4, 8, 16}; 16 json j_array_empty(json::value_t::array); 17 json j_string = "Hello, world"; 18 19 // call empty() 20 std::cout << std::boolalpha; 21 std::cout << j_null.empty() << '\n'; 22 std::cout << j_boolean.empty() << '\n'; 23 std::cout << j_number_integer.empty() << '\n'; 24 std::cout << j_number_float.empty() << '\n'; 25 std::cout << j_object.empty() << '\n'; 26 std::cout << j_object_empty.empty() << '\n'; 27 std::cout << j_array.empty() << '\n'; 28 std::cout << j_array_empty.empty() << '\n'; 29 std::cout << j_string.empty() << '\n'; 30 } 31