1 .. highlightlang:: c

     2 

     3 .. _classobjects:

     4 

     5 Class and Instance Objects

     6 --------------------------

     7 

     8 .. index:: object: class

     9 

    10 Note that the class objects described here represent old-style classes, which

    11 will go away in Python 3. When creating new types for extension modules, you

    12 will want to work with type objects (section :ref:`typeobjects`).

    13 

    14 

    15 .. ctype:: PyClassObject

    16 

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

    18 

    19 

    20 .. cvar:: PyObject* PyClass_Type

    21 

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

    23 

    24    This is the type object for class objects; it is the same object as

    25    ``types.ClassType`` in the Python layer.

    26 

    27 

    28 .. cfunction:: int PyClass_Check(PyObject *o)

    29 

    30    Return true if the object *o* is a class object, including instances of types

    31    derived from the standard class object.  Return false in all other cases.

    32 

    33 

    34 .. cfunction:: int PyClass_IsSubclass(PyObject *klass, PyObject *base)

    35 

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

    37 

    38 

    39 .. index:: object: instance

    40 

    41 There are very few functions specific to instance objects.

    42 

    43 

    44 .. cvar:: PyTypeObject PyInstance_Type

    45 

    46    Type object for class instances.

    47 

    48 

    49 .. cfunction:: int PyInstance_Check(PyObject *obj)

    50 

    51    Return true if *obj* is an instance.

    52 

    53 

    54 .. cfunction:: PyObject* PyInstance_New(PyObject *class, PyObject *arg, PyObject *kw)

    55 

    56    Create a new instance of a specific class.  The parameters *arg* and *kw* are

    57    used as the positional and keyword parameters to the object's constructor.

    58 

    59 

    60 .. cfunction:: PyObject* PyInstance_NewRaw(PyObject *class, PyObject *dict)

    61 

    62    Create a new instance of a specific class without calling its constructor.

    63    *class* is the class of new object.  The *dict* parameter will be used as the

    64    object's :attr:`__dict__`; if *NULL*, a new dictionary will be created for the

    65    instance.