cpython/Doc/library/types.rst

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: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)
The module defines the following names:
.. data:: NoneType
The type of ``None``.
.. data:: TypeType
ClassType
.. index:: builtin: type
The type of type objects (such as returned by :func:`type`) and user-defined
classes without metaclass; alias of the built-in :class:`type`.
.. data:: ObjectType
Alias of the built-in :func:`object`.
.. data:: BooleanType
The type of the :class:`bool` values ``True`` and ``False``; alias of the
built-in :class:`bool`.
.. data:: IntType
LongType
The type of integers (e.g. ``1``); alias of the built-in :class:`int`.
.. 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``); alias of the built-in
:class:`complex`. 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:: 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
DictionaryType
The type of dictionaries (e.g. ``{'Bacon': 1, 'Ham': 0}``); alias of the
built-in :class:`dict`.
.. 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:: 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_info()[2]``.
.. data:: FrameType
The type of frame objects such as found in ``tb.tb_frame`` if ``tb`` is a
traceback object.
.. XXX!
.. 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 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')``.