1#include <iostream>
2#include <nlohmann/json.hpp>
3
4using json = nlohmann::json;
5
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_unsigned = 42u;
13    json j_number_float = 23.42;
14    json j_object = {{"one", 1}, {"two", 2}};
15    json j_array = {1, 2, 4, 8, 16};
16    json j_string = "Hello, world";
17
18    // call operator value_t()
19    json::value_t t_null = j_null;
20    json::value_t t_boolean = j_boolean;
21    json::value_t t_number_integer = j_number_integer;
22    json::value_t t_number_unsigned = j_number_unsigned;
23    json::value_t t_number_float = j_number_float;
24    json::value_t t_object = j_object;
25    json::value_t t_array = j_array;
26    json::value_t t_string = j_string;
27
28    // print types
29    std::cout << std::boolalpha;
30    std::cout << (t_null == json::value_t::null) << '\n';
31    std::cout << (t_boolean == json::value_t::boolean) << '\n';
32    std::cout << (t_number_integer == json::value_t::number_integer) << '\n';
33    std::cout << (t_number_unsigned == json::value_t::number_unsigned) << '\n';
34    std::cout << (t_number_float == json::value_t::number_float) << '\n';
35    std::cout << (t_object == json::value_t::object) << '\n';
36    std::cout << (t_array == json::value_t::array) << '\n';
37    std::cout << (t_string == json::value_t::string) << '\n';
38}
39