RB_ITK/json-develop/docs/examples/README.cpp

#include <iostream>
#include <iomanip>
#include <nlohmann json.hpp="">

using json = nlohmann::json;

int main()
{
    // create a JSON object
    json j =
    {
        {&#34;pi&#34;, 3.141},
        {&#34;happy&#34;, true},
        {&#34;name&#34;, &#34;Niels&#34;},
        {&#34;nothing&#34;, nullptr},
        {
            &#34;answer&#34;, {
                {&#34;everything&#34;, 42}
            }
        },
        {&#34;list&#34;, {1, 0, 2}},
        {
            &#34;object&#34;, {
                {&#34;currency&#34;, &#34;USD&#34;},
                {&#34;value&#34;, 42.99}
            }
        }
    };

    // add new values
    j[&#34;new&#34;][&#34;key&#34;][&#34;value&#34;] = {&#34;another&#34;, &#34;list&#34;};

    // count elements
    auto s = j.size();
    j[&#34;size&#34;] = s;

    // pretty print with indent of 4 spaces
    std::cout &lt;&lt; std::setw(4) &lt;&lt; j &lt;&lt; &#39;\n&#39;;
}