Function function_keys_example

examples/src/jsonpath_examples.cpp:256–292

}

void function_keys_example() 
{
    std::string data = R"(
{
"books":
[
    {
        "title" : "A Wild Sheep Chase",
        "author" : "Haruki Murakami",
        "price" : 22.72
    },
    {
        "title" : "The Night Watch",
        "author" : "Sergei Lukyanenko",
        "price" : 23.58
    },
    {
        "title" : "The Comedians",
        "author" : "Graham Greene",
        "price" : 21.99
    },
    {
        "title" : "The Night Watch",
        "author" : "Phillips, David Atlee"
    }
]
}
    )";

    auto j = jsoncons::json::parse(data);

    // All books that don't have a price
    std::string expr = "$.books[?(!contains(keys(@),'price'))]";

    jsoncons::json result = jsonpath::json_query(j, expr);
    std::cout << result << "\n\n";
}

void function_length_example() 
{