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✏️ Editing: types.rst.txt

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

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

**Source code:** :source:`Lib/types.py`

--------------

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. It is safe to use ``from types import *`` --- the
module does not export any names besides the ones listed here. 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 *
   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)

The module defines the following names:

.. data:: NoneType

The type of ``None``.

.. data:: TypeType

.. index:: builtin: type

The type of type objects (such as returned by :func:`type`); alias of the
   built-in :class:`type`.

.. data:: BooleanType

The type of the :class:`bool` values ``True`` and ``False``; alias of the
   built-in :class:`bool`.

.. versionadded:: 2.3

.. data:: IntType

The type of integers (e.g. ``1``); alias of the built-in :class:`int`.

.. data:: LongType

The type of long integers (e.g. ``1L``); alias of the built-in :class:`long`.

.. data:: FloatType

The type of floating point numbers (e.g. ``1.0``); alias of the built-in
   :class:`float`.

.. data:: ComplexType

The type of complex numbers (e.g. ``1.0j``).  This is not defined if Python was
   built without complex number support.

.. data:: StringType

The type of character strings (e.g. ``'Spam'``); alias of the built-in
   :class:`str`.

.. data:: UnicodeType

The type of Unicode character strings (e.g. ``u'Spam'``).  This is not defined
   if Python was built without Unicode support.  It's an alias of the built-in
   :class:`unicode`.

.. data:: TupleType

The type of tuples (e.g. ``(1, 2, 3, 'Spam')``); alias of the built-in
   :class:`tuple`.

.. data:: ListType

The type of lists (e.g. ``[0, 1, 2, 3]``); alias of the built-in
   :class:`list`.

.. data:: DictType

The type of dictionaries (e.g. ``{'Bacon': 1, 'Ham': 0}``); alias of the
   built-in :class:`dict`.

.. data:: DictionaryType

An alternate name for ``DictType``.

.. data:: FunctionType
          LambdaType

The type of user-defined functions and functions created by :keyword:`lambda`
   expressions.

.. data:: GeneratorType

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

.. versionadded:: 2.2

.. data:: CodeType

.. index:: builtin: compile

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

.. data:: ClassType

The type of user-defined old-style classes.

.. data:: InstanceType

The type of instances of user-defined old-style classes.

.. data:: MethodType

The type of methods of user-defined class instances.

.. data:: UnboundMethodType

An alternate name for ``MethodType``.

.. data:: BuiltinFunctionType
          BuiltinMethodType

The type of built-in functions like :func:`len` or :func:`sys.exit`, and
   methods of built-in classes.  (Here, the term "built-in" means "written in
   C".)

.. data:: ModuleType

The type of modules.

.. data:: FileType

The type of open file objects such as ``sys.stdout``; alias of the built-in
   :class:`file`.

.. data:: XRangeType

.. index:: builtin: xrange

The type of range objects returned by :func:`xrange`; alias of the built-in
   :class:`xrange`.

.. data:: SliceType

.. index:: builtin: slice

The type of objects returned by :func:`slice`; alias of the built-in
   :class:`slice`.

.. data:: EllipsisType

The type of ``Ellipsis``.

.. data:: TracebackType

The type of traceback objects such as found in ``sys.exc_traceback``.

.. data:: FrameType

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

.. data:: BufferType

.. index:: builtin: buffer

The type of buffer objects created by the :func:`buffer` function.

.. data:: DictProxyType

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

.. data:: NotImplementedType

The type of ``NotImplemented``

.. data:: GetSetDescriptorType

The type of objects defined in extension modules with ``PyGetSetDef``, such
   as ``FrameType.f_locals`` or ``array.array.typecode``.  This type is used as
   descriptor for object attributes; it has the same purpose as the
   :class:`property` type, but for classes defined in extension modules.

.. versionadded:: 2.5

.. data:: MemberDescriptorType

The type of objects defined in extension modules with ``PyMemberDef``, such
   as ``datetime.timedelta.days``.  This type is used as descriptor for simple C
   data members which use standard conversion functions; it has the same purpose
   as the :class:`property` type, but for classes defined in extension modules.

.. impl-detail::

In other implementations of Python, this type may be identical to
      ``GetSetDescriptorType``.

.. versionadded:: 2.5

.. data:: StringTypes

A sequence containing ``StringType`` and ``UnicodeType`` used to facilitate
   easier checking for any string object.  Using this is more portable than using a
   sequence of the two string types constructed elsewhere since it only contains
   ``UnicodeType`` if it has been built in the running version of Python.  For
   example: ``isinstance(s, types.StringTypes)``.

.. versionadded:: 2.2

MR SKB