cpython/Doc/c-api/int.rst

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.. highlightlang:: c
.. _intobjects:
Plain Integer Objects
---------------------
.. index:: object: integer
.. ctype:: PyIntObject
This subtype of :ctype:`PyObject` represents a Python integer object.
.. cvar:: PyTypeObject PyInt_Type
.. index:: single: IntType (in modules types)
This instance of :ctype:`PyTypeObject` represents the Python plain integer type.
This is the same object as ``int`` and ``types.IntType``.
.. cfunction:: int PyInt_Check(PyObject *o)
Return true if *o* is of type :cdata:`PyInt_Type` or a subtype of
:cdata:`PyInt_Type`.
.. versionchanged:: 2.2
Allowed subtypes to be accepted.
.. cfunction:: int PyInt_CheckExact(PyObject *o)
Return true if *o* is of type :cdata:`PyInt_Type`, but not a subtype of
:cdata:`PyInt_Type`.
.. versionadded:: 2.2
.. cfunction:: PyObject* PyInt_FromString(char *str, char **pend, int base)
Return a new :ctype:`PyIntObject` or :ctype:`PyLongObject` based on the string
value in *str*, which is interpreted according to the radix in *base*. If
*pend* is non-*NULL*, ``*pend`` will point to the first character in *str* which
follows the representation of the number. If *base* is ``0``, the radix will be
determined based on the leading characters of *str*: if *str* starts with
``'0x'`` or ``'0X'``, radix 16 will be used; if *str* starts with ``'0'``, radix
8 will be used; otherwise radix 10 will be used. If *base* is not ``0``, it
must be between ``2`` and ``36``, inclusive. Leading spaces are ignored. If
there are no digits, :exc:`ValueError` will be raised. If the string represents
a number too large to be contained within the machine's :ctype:`long int` type
and overflow warnings are being suppressed, a :ctype:`PyLongObject` will be
returned. If overflow warnings are not being suppressed, *NULL* will be
returned in this case.
.. cfunction:: PyObject* PyInt_FromLong(long ival)
Create a new integer object with a value of *ival*.
The current implementation keeps an array of integer objects for all integers
between ``-5`` and ``256``, when you create an int in that range you actually
just get back a reference to the existing object. So it should be possible to
change the value of ``1``. I suspect the behaviour of Python in this case is
undefined. :-)
.. cfunction:: PyObject* PyInt_FromSsize_t(Py_ssize_t ival)
Merged revisions 73286,73294,73296,73459,73462-73463,73544,73576-73577,73595-73596,73693-73694,73704-73705,73707,73713,73937-73940,73945,73951,73979 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r73286 | georg.brandl | 2009-06-08 09:57:35 +0200 (Mo, 08 Jun 2009) | 1 line Remove period from end of headings. ........ r73294 | georg.brandl | 2009-06-08 15:34:52 +0200 (Mo, 08 Jun 2009) | 1 line #6194: O_SHLOCK/O_EXLOCK are not really more platform independent than lockf(). ........ r73296 | georg.brandl | 2009-06-08 18:03:41 +0200 (Mo, 08 Jun 2009) | 1 line #6238: add fillchar to string.just function family. ........ r73459 | raymond.hettinger | 2009-06-17 03:43:47 +0200 (Mi, 17 Jun 2009) | 1 line Add usage note. ........ r73462 | georg.brandl | 2009-06-17 11:36:21 +0200 (Mi, 17 Jun 2009) | 1 line #6295: clarify blocking behavior of getch(). ........ r73463 | georg.brandl | 2009-06-17 11:43:31 +0200 (Mi, 17 Jun 2009) | 1 line #6255: document PyInt_FromSize_t. ........ r73544 | georg.brandl | 2009-06-24 08:41:19 +0200 (Mi, 24 Jun 2009) | 1 line #6332: fix word dupes throughout the source. ........ r73576 | benjamin.peterson | 2009-06-27 01:37:06 +0200 (Sa, 27 Jun 2009) | 1 line document is_declared_global() ........ r73577 | benjamin.peterson | 2009-06-27 16:16:23 +0200 (Sa, 27 Jun 2009) | 1 line link to extensive generator docs in the reference manual ........ r73595 | ezio.melotti | 2009-06-28 01:45:39 +0200 (So, 28 Jun 2009) | 1 line stmt and setup can contain multiple statements, see #5896 ........ r73596 | ezio.melotti | 2009-06-28 02:07:45 +0200 (So, 28 Jun 2009) | 1 line Fixed a wrong apostrophe ........ r73693 | jesse.noller | 2009-06-29 20:20:34 +0200 (Mo, 29 Jun 2009) | 1 line Bug 5906: add a documentation note for unix daemons vs. multiprocessing daemons ........ r73694 | jesse.noller | 2009-06-29 20:24:26 +0200 (Mo, 29 Jun 2009) | 1 line Issue 5740: multiprocessing.connection.* authkey fixes ........ r73704 | georg.brandl | 2009-06-30 18:15:43 +0200 (Di, 30 Jun 2009) | 1 line #6376: fix copy-n-paste oversight. ........ r73705 | georg.brandl | 2009-06-30 18:17:28 +0200 (Di, 30 Jun 2009) | 1 line #6374: add a bit of explanation about shell=True on Windows. ........ r73707 | georg.brandl | 2009-06-30 18:35:11 +0200 (Di, 30 Jun 2009) | 1 line #6371: fix link targets. ........ r73713 | ezio.melotti | 2009-07-01 00:56:16 +0200 (Mi, 01 Jul 2009) | 1 line Fixed a backslash that was not supposed to be there ........ r73937 | georg.brandl | 2009-07-11 12:12:36 +0200 (Sa, 11 Jul 2009) | 1 line Fix style. ........ r73938 | georg.brandl | 2009-07-11 12:14:54 +0200 (Sa, 11 Jul 2009) | 1 line #6446: fix import_spam() function to use correct error and reference handling. ........ r73939 | georg.brandl | 2009-07-11 12:18:10 +0200 (Sa, 11 Jul 2009) | 1 line #6448: clarify docs for find_module(). ........ r73940 | georg.brandl | 2009-07-11 12:37:38 +0200 (Sa, 11 Jul 2009) | 1 line #6430: add note about size of "u" type. ........ r73945 | georg.brandl | 2009-07-11 12:51:31 +0200 (Sa, 11 Jul 2009) | 1 line #6456: clarify the meaning of constants used as arguments to nl_langinfo(). ........ r73951 | georg.brandl | 2009-07-11 16:23:38 +0200 (Sa, 11 Jul 2009) | 2 lines array.array is actually a class. ........ r73979 | benjamin.peterson | 2009-07-12 18:56:54 +0200 (So, 12 Jul 2009) | 1 line add versionadded ........
2009-10-27 11:29:22 -03:00
Create a new integer object with a value of *ival*. If the value is larger
than ``LONG_MAX`` or smaller than ``LONG_MIN``, a long integer object is
returned.
.. versionadded:: 2.5
.. cfunction:: PyObject* PyInt_FromSize_t(size_t ival)
Create a new integer object with a value of *ival*. If the value exceeds
``LONG_MAX``, a long integer object is returned.
.. versionadded:: 2.5
.. cfunction:: long PyInt_AsLong(PyObject *io)
Will first attempt to cast the object to a :ctype:`PyIntObject`, if it is not
already one, and then return its value. If there is an error, ``-1`` is
returned, and the caller should check ``PyErr_Occurred()`` to find out whether
there was an error, or whether the value just happened to be -1.
.. cfunction:: long PyInt_AS_LONG(PyObject *io)
Return the value of the object *io*. No error checking is performed.
.. cfunction:: unsigned long PyInt_AsUnsignedLongMask(PyObject *io)
Will first attempt to cast the object to a :ctype:`PyIntObject` or
:ctype:`PyLongObject`, if it is not already one, and then return its value as
unsigned long. This function does not check for overflow.
.. versionadded:: 2.3
.. cfunction:: unsigned PY_LONG_LONG PyInt_AsUnsignedLongLongMask(PyObject *io)
Will first attempt to cast the object to a :ctype:`PyIntObject` or
:ctype:`PyLongObject`, if it is not already one, and then return its value as
unsigned long long, without checking for overflow.
.. versionadded:: 2.3
.. cfunction:: Py_ssize_t PyInt_AsSsize_t(PyObject *io)
Will first attempt to cast the object to a :ctype:`PyIntObject` or
:ctype:`PyLongObject`, if it is not already one, and then return its value as
:ctype:`Py_ssize_t`.
.. versionadded:: 2.5
.. cfunction:: long PyInt_GetMax()
.. index:: single: LONG_MAX
Return the system's idea of the largest integer it can handle
(:const:`LONG_MAX`, as defined in the system header files).
.. cfunction:: int PyInt_ClearFreeList(void)
Clear the integer free list. Return the number of items that could not
be freed.
.. versionadded:: 2.6