JsonValue
=========

.. cpp:class:: pandas::JsonValue

   pandas C++ class.

Example
-------

.. code-block:: cpp

   #include <pandas/pandas.h>
   using namespace pandas;

   // Use JsonValue
   JsonValue obj;
   // ... operations ...

Constructors
------------

.. list-table::
   :widths: 55 25 20
   :header-rows: 1

   * - Signature
     - Location
     - Example
   * - ``JsonValue() = default``
     - json.h:44
     - :ref:`View <example-jsonvalue-jsonvalue-0>`
   * - ``JsonValue(const JsonValue&) = default``
     - json.h:45
     - :ref:`View <example-jsonvalue-jsonvalue-1>`
   * - ``JsonValue(JsonValue&&) noexcept = default``
     - json.h:46
     - :ref:`View <example-jsonvalue-jsonvalue-2>`

Type Checking
-------------

.. list-table::
   :widths: 40 20 15 25
   :header-rows: 1

   * - Signature
     - Return Type
     - Location
     - Example
   * - ``bool is_array() const { return std::holds_alternative<JsonArray>(v)``
     - bool
     - json.h:63
     - 
   * - ``bool is_bool() const { return std::holds_alternative<bool>(v)``
     - bool
     - json.h:59
     - 
   * - ``bool is_double() const { return std::holds_alternative<double>(v)``
     - bool
     - json.h:61
     - 
   * - ``bool is_int() const { return std::holds_alternative<int64_t>(v)``
     - bool
     - json.h:60
     - :ref:`View <example-jsonvalue-is_int-3>`
   * - ``bool is_null() const { return std::holds_alternative<std::monostate>(v)``
     - bool
     - json.h:58
     - :ref:`View <example-jsonvalue-is_null-4>`
   * - ``bool is_object() const { return std::holds_alternative<JsonObject>(v)``
     - bool
     - json.h:64
     - :ref:`View <example-jsonvalue-is_object-5>`
   * - ``bool is_string() const { return std::holds_alternative<std::string>(v)``
     - bool
     - json.h:62
     - 


Code Examples
-------------

The following examples are extracted from the test suite.

.. _example-jsonvalue-jsonvalue-0:

.. dropdown:: JsonValue (pd_test_5_all.cpp:81168)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 81158
      :emphasize-lines: 11

      void case_1_default_is_null(int& local_fail) {
          std::cout << "-- case_1_default_is_null\n";
          JsonValue v;
          pandas_tests::check(v.is_null(),
              "case_1_default_is_null.is_null()", local_fail);
      }
      
      void case_2_bool_true_false(int& local_fail) {
          std::cout << "-- case_2_bool_true_false\n";
          check_str("case_2_bool_true_false.true_str()",  "True",
                    [] { return PIO::json_value_to_string(JsonValue(true)); }, local_fail);
          check_str("case_2_bool_true_false.false_str()", "False",
                    [] { return PIO::json_value_to_string(JsonValue(false)); }, local_fail);
      }
      
      void case_3_int64_range(int& local_fail) {
          std::cout << "-- case_3_int64_range\n";
          check_str("case_3_int64_range.zero()", "0",
                    [] { return PIO::json_value_to_string(JsonValue(int64_t{0})); },
                    local_fail);
          check_str("case_3_int64_range.neg()", "-12345",

.. _example-jsonvalue-jsonvalue-1:

.. dropdown:: JsonValue (pd_test_5_all.cpp:81168)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 81158
      :emphasize-lines: 11

      void case_1_default_is_null(int& local_fail) {
          std::cout << "-- case_1_default_is_null\n";
          JsonValue v;
          pandas_tests::check(v.is_null(),
              "case_1_default_is_null.is_null()", local_fail);
      }
      
      void case_2_bool_true_false(int& local_fail) {
          std::cout << "-- case_2_bool_true_false\n";
          check_str("case_2_bool_true_false.true_str()",  "True",
                    [] { return PIO::json_value_to_string(JsonValue(true)); }, local_fail);
          check_str("case_2_bool_true_false.false_str()", "False",
                    [] { return PIO::json_value_to_string(JsonValue(false)); }, local_fail);
      }
      
      void case_3_int64_range(int& local_fail) {
          std::cout << "-- case_3_int64_range\n";
          check_str("case_3_int64_range.zero()", "0",
                    [] { return PIO::json_value_to_string(JsonValue(int64_t{0})); },
                    local_fail);
          check_str("case_3_int64_range.neg()", "-12345",

.. _example-jsonvalue-jsonvalue-2:

.. dropdown:: JsonValue (pd_test_5_all.cpp:81168)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 81158
      :emphasize-lines: 11

      void case_1_default_is_null(int& local_fail) {
          std::cout << "-- case_1_default_is_null\n";
          JsonValue v;
          pandas_tests::check(v.is_null(),
              "case_1_default_is_null.is_null()", local_fail);
      }
      
      void case_2_bool_true_false(int& local_fail) {
          std::cout << "-- case_2_bool_true_false\n";
          check_str("case_2_bool_true_false.true_str()",  "True",
                    [] { return PIO::json_value_to_string(JsonValue(true)); }, local_fail);
          check_str("case_2_bool_true_false.false_str()", "False",
                    [] { return PIO::json_value_to_string(JsonValue(false)); }, local_fail);
      }
      
      void case_3_int64_range(int& local_fail) {
          std::cout << "-- case_3_int64_range\n";
          check_str("case_3_int64_range.zero()", "0",
                    [] { return PIO::json_value_to_string(JsonValue(int64_t{0})); },
                    local_fail);
          check_str("case_3_int64_range.neg()", "-12345",

.. _example-jsonvalue-is_int-3:

.. dropdown:: is_int (pd_test_5_all.cpp:81116)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 81106
      :emphasize-lines: 11

      
      static void check_lookup_int(const std::string& label,
                                   const JsonObject& root,
                                   const std::vector<std::string>& path,
                                   int64_t expected_int,
                                   int& local_fail) {
          bool ok = false;
          std::string err;
          try {
              const JsonValue* hit = PIO::lookup_path(root, path);
              if (hit && hit->is_int() && std::get<int64_t>(hit->v) == expected_int) {
                  ok = true;
              }
          } catch (const std::exception& e) {
              err = std::string("THREW: ") + e.what();
          }
          pandas_tests::check(ok, label, local_fail);
          if (!ok && !err.empty()) std::cout << "  " << err << "\n";
      }
      
      static void check_lookup_object(const std::string& label,

.. _example-jsonvalue-is_null-4:

.. dropdown:: is_null (pd_test_5_all.cpp:71470)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 71460
      :emphasize-lines: 11

          bool ok = (got == expected);
          pandas_tests::check(ok, label, local_fail);
          if (!ok) {
              std::cout << "    expected: [" << expected << "]\n"
                        << "    got:      [" << got << "]\n";
          }
          return ok;
      }
      
      static numpy::object_ obj_none() {
          return numpy::object_();  // default-constructed -> is_null() == true
      }
      
      static numpy::object_ obj_nan() {
          return numpy::object_(std::numeric_limits<double>::quiet_NaN());
      }
      
      static numpy::object_ obj_int(int64_t v) {
          return numpy::object_(v);
      }
      

.. _example-jsonvalue-is_object-5:

.. dropdown:: is_object (pd_test_3_all.cpp:626)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 616
      :emphasize-lines: 11

              throw std::runtime_error("pd_test_3_all_index_dtype_checks failed: int is_numeric");
          }
          if (!int_dtype.is_integer()) {
              std::cout << "  [FAIL] : in pd_test_3_all_index_dtype_checks() : int should be integer" << std::endl;
              throw std::runtime_error("pd_test_3_all_index_dtype_checks failed: int is_integer");
          }
          if (int_dtype.is_floating()) {
              std::cout << "  [FAIL] : in pd_test_3_all_index_dtype_checks() : int should not be floating" << std::endl;
              throw std::runtime_error("pd_test_3_all_index_dtype_checks failed: int is_floating");
          }
          if (int_dtype.is_object()) {
              std::cout << "  [FAIL] : in pd_test_3_all_index_dtype_checks() : int should not be object" << std::endl;
              throw std::runtime_error("pd_test_3_all_index_dtype_checks failed: int is_object");
          }
      
          // Test with float index
          pandas::IndexDtype<double> float_dtype;
          if (!float_dtype.is_numeric()) {
              std::cout << "  [FAIL] : in pd_test_3_all_index_dtype_checks() : float should be numeric" << std::endl;
              throw std::runtime_error("pd_test_3_all_index_dtype_checks failed: float is_numeric");
          }