#format rst

Implementing ``__str__`` and ``__repr__``  
=========================================

When coding a subclass of PyObject, it is somewhat tricky to get a correct implementation of ``__repr__`` and ``__str__`` which works through the exposed methods and the related builtins, while also supporting derived types. Here are some quick guidelines to help with this problem.

Same implementation for ``__repr__`` and ``__str__`` 
----------------------------------------------------

 1. Write the exposed method::

      @ExposedMethod(names = {"__str__", "__repr__"})
      final PyString foo_toString() {
          // Implementation
      }

 2. Override toString() and manually call exposed method::

      @Override
      public String toString() {
          return foo__repr__().toString()
      }

[The second step is to keep the builtins `repr()` and `str()` working. ``repr()`` calls ``PyObject#__repr__()``, which calls ``Object#toString()``. And ``str()`` calls ``PyObject#__str__()`` which calls ``PyObject#__repr__()``]

Different implementations for ``__str__`` and ``__repr__``
-----------------------------------------------------------


 1. Write the exposed ``__str__`` and call it from the overriden ``__str__``::

      @ExposedMethod
      final PyString foo___str__() {
          // Implementation
      }

      @Override
      public PyString __str__() {
          return foo__str__();
      }

 2. Same thing for ``__repr__``::

      @ExposedMethod
      final PyString foo___repr__() {
          // Implementation
      }

      @Override
      public PyString __repr__() {
          return foo__repr__();
      }

 3. Override ``toString``::

      @Override
      public String toString() {
          return foo___str__().toString() 
      }

[Now, once you have overridden the three important methods, you don't have to care about the interrelations which are present on the default implementations of ``PyObject``]

Only implement ``__str__``
--------------------------

Follow the step 1 of the previous recipe. Optionally you can also follow the step 3 if you want to map ``toString()`` to ``__str__()`` .