5.15 types -- Names for built-in types

Python 2.5

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5.15 `types` -- 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. 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 int() and str() are also names for the corresponding types. This is now the preferred way to access the type instead of using the 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:

NoneType: The type of None.

TypeType: The type of type objects (such as returned by type()).

BooleanType: The type of the bool values True and False; this is an alias of the built-in bool() function. New in version 2.3.

IntType: The type of integers (e.g. 1).

LongType: The type of long integers (e.g. 1L).

FloatType: The type of floating point numbers (e.g. 1.0).

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

StringType: The type of character strings (e.g. 'Spam').

UnicodeType: The type of Unicode character strings (e.g. u'Spam'). This is not defined if Python was built without Unicode support.

TupleType: The type of tuples (e.g. (1, 2, 3, 'Spam')).

ListType: The type of lists (e.g. [0, 1, 2, 3]).

DictType: The type of dictionaries (e.g. {'Bacon': 1, 'Ham': 0}).

DictionaryType: An alternate name for DictType.

FunctionType: The type of user-defined functions and lambdas.

LambdaType: An alternate name for FunctionType.

GeneratorType: The type of generator-iterator objects, produced by calling a generator function. New in version 2.2.

CodeType: The type for code objects such as returned by compile().

ClassType: The type of user-defined classes.

InstanceType: The type of instances of user-defined classes.

MethodType: The type of methods of user-defined class instances.

UnboundMethodType: An alternate name for MethodType.

BuiltinFunctionType: The type of built-in functions like len() or sys.exit().

BuiltinMethodType: An alternate name for BuiltinFunction.

ModuleType: The type of modules.

FileType: The type of open file objects such as sys.stdout.

XRangeType: The type of range objects returned by xrange().

SliceType: The type of objects returned by slice().

EllipsisType: The type of Ellipsis.

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

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

BufferType: The type of buffer objects created by the buffer() function.

DictProxyType: The type of dict proxies, such as TypeType.__dict__.

NotImplementedType: The type of NotImplemented

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'). New in version 2.5.

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'). New in version 2.5.

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). New in version 2.2.

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