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✏️ Editing: class.rst.txt

.. highlightlang:: c

.. _classobjects:

Class and Instance Objects
--------------------------

.. index:: object: class

Note that the class objects described here represent old-style classes, which
will go away in Python 3. When creating new types for extension modules, you
will want to work with type objects (section :ref:`typeobjects`).

.. c:type:: PyClassObject

The C structure of the objects used to describe built-in classes.

.. c:var:: PyObject* PyClass_Type

.. index:: single: ClassType (in module types)

This is the type object for class objects; it is the same object as
   ``types.ClassType`` in the Python layer.

.. c:function:: int PyClass_Check(PyObject *o)

Return true if the object *o* is a class object, including instances of types
   derived from the standard class object.  Return false in all other cases.

.. c:function:: int PyClass_IsSubclass(PyObject *klass, PyObject *base)

Return true if *klass* is a subclass of *base*. Return false in all other cases.

.. index:: object: instance

There are very few functions specific to instance objects.

.. c:var:: PyTypeObject PyInstance_Type

Type object for class instances.

.. c:function:: int PyInstance_Check(PyObject *obj)

Return true if *obj* is an instance.

.. c:function:: PyObject* PyInstance_New(PyObject *class, PyObject *arg, PyObject *kw)

Create a new instance of a specific class.  The parameters *arg* and *kw* are
   used as the positional and keyword parameters to the object's constructor.

.. c:function:: PyObject* PyInstance_NewRaw(PyObject *class, PyObject *dict)

Create a new instance of a specific class without calling its constructor.
   *class* is the class of new object.  The *dict* parameter will be used as the
   object's :attr:`~object.__dict__`; if *NULL*, a new dictionary will be created for the
   instance.

MR SKB