NA_t
====

.. cpp:class:: pandas::NA_t

   Utility class for pandas operations.

Example
-------

.. code-block:: cpp

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

   // Use NA_t
   NA_t obj;
   // ... operations ...

Conversion
----------

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

   * - Signature
     - Return Type
     - Location
     - Example
   * - ``explicit constexpr operator bool() const noexcept``
     - explicit constexpr operator
     - pd_na.h:49
     - :ref:`View <example-na_t-bool-0>`

Other Methods
-------------

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

   * - Signature
     - Return Type
     - Location
     - Example
   * - ``std::string repr() const``
     - constexpr bool operator>=(const T&) const noexcept { return false; } std::string
     - pd_na.h:46
     - :ref:`View <example-na_t-repr-1>`


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

The following examples are extracted from the test suite.

.. _example-na_t-bool-0:

.. dropdown:: bool (pd_test_3_all.cpp:1568)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 1558
      :emphasize-lines: 11

          }
      
          std::cout << " -> tests passed" << std::endl;
      }
      
      // ============================================================================
      // Category 9: NA Functions
      // ============================================================================
      
      void pd_test_3_all_na_functions() {
          std::cout << "========= NA_t.bool() and is_na<T> ===================";
      
          // Test NA_t bool conversion
          pandas::NA_t na_val;
          bool na_as_bool = static_cast<bool>(na_val);
          if (na_as_bool != false) {
              std::cout << "  [FAIL] : in pd_test_3_all_na_functions() : NA should convert to false" << std::endl;
              throw std::runtime_error("pd_test_3_all_na_functions failed: NA bool conversion");
          }
      
          // Test NA_t equality with itself

.. _example-na_t-repr-1:

.. dropdown:: repr (pd_test_1_all.cpp:10906)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 10896
      :emphasize-lines: 11

          std::cout << " -> tests passed" << std::endl;
      }
      
      void pd_test_extension_index_repr() {
          std::cout << "========= repr =========================";
      
          pandas::CategoricalArray arr({"a", "b", "c"});
          // Use ExtensionIndex<CategoricalArray> directly to test base class repr
          pandas::ExtensionIndex<pandas::CategoricalArray> idx(arr, "test");
      
          std::string repr_str = idx.repr();
      
          bool passed = (!repr_str.empty() && repr_str.find("ExtensionIndex") != std::string::npos);
          if (!passed) {
              std::cout << "  [FAIL] : in pd_test_extension_index_repr() : repr check failed" << std::endl;
              throw std::runtime_error("pd_test_extension_index_repr failed");
          }
      
          std::cout << " -> tests passed" << std::endl;
      }