NullableString
==============

.. cpp:class:: pandas::NullableString

   pandas C++ class.

Example
-------

.. code-block:: cpp

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

   // Use NullableString
   NullableString obj;
   // ... operations ...

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

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

   * - Signature
     - Return Type
     - Location
     - Example
   * - ``bool has_value() const { return value.has_value()``
     - bool
     - pd_nullable.h:53
     - :ref:`View <example-nullablestring-has_value-0>`
   * - ``NullableString(const char\* s) : value(s ? std::optional<std::string>(s) : std::nullopt)``
     - NullableString(const char\* s) :
     - pd_nullable.h:49
     - :ref:`View <example-nullablestring-value-1>`
   * - ``NullableString(const std::string& s) : value(s)``
     - NullableString(const std::string& s) :
     - pd_nullable.h:50
     - :ref:`View <example-nullablestring-value-2>`
   * - ``NullableString(std::nullopt_t) : value(std::nullopt)``
     - NullableString(std::nullopt_t) :
     - pd_nullable.h:52
     - :ref:`View <example-nullablestring-value-3>`


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

The following examples are extracted from the test suite.

.. _example-nullablestring-has_value-0:

.. dropdown:: has_value (pd_test_1_all.cpp:88)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 78
      :emphasize-lines: 11

              // T & T = T, T & F = F, T & NA = NA
              // F & T = F, F & F = F, F & NA = F (False dominates)
              // NA & T = NA, NA & F = F, NA & NA = NA
      
              pandas::BooleanArray t({std::optional<bool>(true)});
              pandas::BooleanArray f({std::optional<bool>(false)});
              pandas::BooleanArray na({std::nullopt});
      
              // T & T = T
              auto tt = (t & t);
              if (!tt[0].has_value() || !tt[0].value()) {
                  std::cout << "  [FAIL] : in pd_test_boolean_array_kleene_and() : T & T should be T" << std::endl;
                  throw std::runtime_error("pd_test_boolean_array_kleene_and failed: T & T");
              }
      
              // T & F = F
              auto tf = (t & f);
              if (!tf[0].has_value() || tf[0].value()) {
                  std::cout << "  [FAIL] : in pd_test_boolean_array_kleene_and() : T & F should be F" << std::endl;
                  throw std::runtime_error("pd_test_boolean_array_kleene_and failed: T & F");
              }

.. _example-nullablestring-value-1:

.. dropdown:: value (pd_test_1_all.cpp:88)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 78
      :emphasize-lines: 11

              // T & T = T, T & F = F, T & NA = NA
              // F & T = F, F & F = F, F & NA = F (False dominates)
              // NA & T = NA, NA & F = F, NA & NA = NA
      
              pandas::BooleanArray t({std::optional<bool>(true)});
              pandas::BooleanArray f({std::optional<bool>(false)});
              pandas::BooleanArray na({std::nullopt});
      
              // T & T = T
              auto tt = (t & t);
              if (!tt[0].has_value() || !tt[0].value()) {
                  std::cout << "  [FAIL] : in pd_test_boolean_array_kleene_and() : T & T should be T" << std::endl;
                  throw std::runtime_error("pd_test_boolean_array_kleene_and failed: T & T");
              }
      
              // T & F = F
              auto tf = (t & f);
              if (!tf[0].has_value() || tf[0].value()) {
                  std::cout << "  [FAIL] : in pd_test_boolean_array_kleene_and() : T & F should be F" << std::endl;
                  throw std::runtime_error("pd_test_boolean_array_kleene_and failed: T & F");
              }

.. _example-nullablestring-value-2:

.. dropdown:: value (pd_test_1_all.cpp:88)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 78
      :emphasize-lines: 11

              // T & T = T, T & F = F, T & NA = NA
              // F & T = F, F & F = F, F & NA = F (False dominates)
              // NA & T = NA, NA & F = F, NA & NA = NA
      
              pandas::BooleanArray t({std::optional<bool>(true)});
              pandas::BooleanArray f({std::optional<bool>(false)});
              pandas::BooleanArray na({std::nullopt});
      
              // T & T = T
              auto tt = (t & t);
              if (!tt[0].has_value() || !tt[0].value()) {
                  std::cout << "  [FAIL] : in pd_test_boolean_array_kleene_and() : T & T should be T" << std::endl;
                  throw std::runtime_error("pd_test_boolean_array_kleene_and failed: T & T");
              }
      
              // T & F = F
              auto tf = (t & f);
              if (!tf[0].has_value() || tf[0].value()) {
                  std::cout << "  [FAIL] : in pd_test_boolean_array_kleene_and() : T & F should be F" << std::endl;
                  throw std::runtime_error("pd_test_boolean_array_kleene_and failed: T & F");
              }

.. _example-nullablestring-value-3:

.. dropdown:: value (pd_test_1_all.cpp:88)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 78
      :emphasize-lines: 11

              // T & T = T, T & F = F, T & NA = NA
              // F & T = F, F & F = F, F & NA = F (False dominates)
              // NA & T = NA, NA & F = F, NA & NA = NA
      
              pandas::BooleanArray t({std::optional<bool>(true)});
              pandas::BooleanArray f({std::optional<bool>(false)});
              pandas::BooleanArray na({std::nullopt});
      
              // T & T = T
              auto tt = (t & t);
              if (!tt[0].has_value() || !tt[0].value()) {
                  std::cout << "  [FAIL] : in pd_test_boolean_array_kleene_and() : T & T should be T" << std::endl;
                  throw std::runtime_error("pd_test_boolean_array_kleene_and failed: T & T");
              }
      
              // T & F = F
              auto tf = (t & f);
              if (!tf[0].has_value() || tf[0].value()) {
                  std::cout << "  [FAIL] : in pd_test_boolean_array_kleene_and() : T & F should be F" << std::endl;
                  throw std::runtime_error("pd_test_boolean_array_kleene_and failed: T & F");
              }