Doc/library/types.rst

:mod:`types` --- Names for built-in types
=========================================

.. module:: types
   :synopsis: Names for built-in types.


This module defines names for some object types that are used by the standard
Python interpreter, but not for the types defined by various extension modules.
Also, it does not include some of the types that arise during processing such as
the ``listiterator`` type. New names exported by future versions of this module
will all end in ``Type``.

Typical use is for functions that do different things depending on their
argument types, like the following::

   from types import IntType
   def delete(mylist, item):
       if type(item) is IntType:
          del mylist[item]
       else:
          mylist.remove(item)

Starting in Python 2.2, built-in factory functions such as :func:`int` and
:func:`str` are also names for the corresponding types.  This is now the
preferred way to access the type instead of using the :mod:`types` module.
Accordingly, the example above should be written as follows::

   def delete(mylist, item):
       if isinstance(item, int):
          del mylist[item]
       else:
          mylist.remove(item)

Starting in Python 3.0 all types that are also available as builtins are no
longer exposed through the types module.

The module defines the following names:

.. data:: FunctionType
          LambdaType

   The type of user-defined functions and lambdas.


.. data:: GeneratorType

   The type of :term:`generator`-iterator objects, produced by calling a
   generator function.


.. data:: CodeType

   .. index:: builtin: compile

   The type for code objects such as returned by :func:`compile`.


.. data:: MethodType
          UnboundMethdType

   The type of methods of user-defined class instances.


.. data:: BuiltinFunctionType
          BuiltinMethodType

   The type of built-in functions like :func:`len` or :func:`sys.exit`.


.. data:: ModuleType

   The type of modules.


.. data:: TracebackType

   The type of traceback objects such as found in ``sys.exc_info()[2]``.


.. data:: FrameType

   The type of frame objects such as found in ``tb.tb_frame`` if ``tb`` is a
   traceback object.


.. data:: DictProxyType

   The type of dict proxies, such as ``type.__dict__``.


.. data:: GetSetDescriptorType

   The type of objects defined in extension modules with ``PyGetSetDef``, such as
   ``FrameType.f_locals`` or ``array.array.typecode``.  This constant is not
   defined in implementations of Python that do not have such extension types, so
   for portable code use ``hasattr(types, 'GetSetDescriptorType')``.


.. data:: MemberDescriptorType

   The type of objects defined in extension modules with ``PyMemberDef``, such as
   ``datetime.timedelta.days``.  This constant is not defined in implementations of
   Python that do not have such extension types, so for portable code use
   ``hasattr(types, 'MemberDescriptorType')``.