[Global]: loading init

deps/json/docs/examples/at__json_pointer.cpp

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+#include <iostream>
+#include <nlohmann/json.hpp>
+
+using json = nlohmann::json;
+using namespace nlohmann::literals;
+
+int main()
+{
+    // create a JSON value
+    json j =
+    {
+        {"number", 1}, {"string", "foo"}, {"array", {1, 2}}
+    };
+
+    // read-only access
+
+    // output element with JSON pointer "/number"
+    std::cout << j.at("/number"_json_pointer) << '\n';
+    // output element with JSON pointer "/string"
+    std::cout << j.at("/string"_json_pointer) << '\n';
+    // output element with JSON pointer "/array"
+    std::cout << j.at("/array"_json_pointer) << '\n';
+    // output element with JSON pointer "/array/1"
+    std::cout << j.at("/array/1"_json_pointer) << '\n';
+
+    // writing access
+
+    // change the string
+    j.at("/string"_json_pointer) = "bar";
+    // output the changed string
+    std::cout << j["string"] << '\n';
+
+    // change an array element
+    j.at("/array/1"_json_pointer) = 21;
+    // output the changed array
+    std::cout << j["array"] << '\n';
+
+    // out_of_range.106
+    try
+    {
+        // try to use an array index with leading '0'
+        json::reference ref = j.at("/array/01"_json_pointer);
+    }
+    catch (const json::parse_error& e)
+    {
+        std::cout << e.what() << '\n';
+    }
+
+    // out_of_range.109
+    try
+    {
+        // try to use an array index that is not a number
+        json::reference ref = j.at("/array/one"_json_pointer);
+    }
+    catch (const json::parse_error& e)
+    {
+        std::cout << e.what() << '\n';
+    }
+
+    // out_of_range.401
+    try
+    {
+        // try to use an invalid array index
+        json::reference ref = j.at("/array/4"_json_pointer);
+    }
+    catch (const json::out_of_range& e)
+    {
+        std::cout << e.what() << '\n';
+    }
+
+    // out_of_range.402
+    try
+    {
+        // try to use the array index '-'
+        json::reference ref = j.at("/array/-"_json_pointer);
+    }
+    catch (const json::out_of_range& e)
+    {
+        std::cout << e.what() << '\n';
+    }
+
+    // out_of_range.403
+    try
+    {
+        // try to use a JSON pointer to a nonexistent object key
+        json::const_reference ref = j.at("/foo"_json_pointer);
+    }
+    catch (const json::out_of_range& e)
+    {
+        std::cout << e.what() << '\n';
+    }
+
+    // out_of_range.404
+    try
+    {
+        // try to use a JSON pointer that cannot be resolved
+        json::reference ref = j.at("/number/foo"_json_pointer);
+    }
+    catch (const json::out_of_range& e)
+    {
+        std::cout << e.what() << '\n';
+    }
+}