# Integer Objects

All integers are implemented as “long” integer objects of arbitrary size.

`PyLongObject`

  This subtype of `PyObject` represents a Python integer object.

PyTypeObject `PyLong_Type`

  This instance of `PyTypeObject` represents the Python integer type. This is the same object as `int` in the Python layer.

int `PyLong_Check`( PyObject *p)

  Return true if its argument is a `PyLongObject` or a subtype of `PyLongObject`.

int `PyLong_CheckExact`( PyObject *p)

  Return true if its argument is a `PyLongObject`, but not a subtype of `PyLongObject`.

PyObject* `PyLong_FromLong`(long v)
  Return value: New reference.

  Return a new `PyLongObject` object from v, or NULL on failure.

  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. :-)

PyObject* `PyLong_FromUnsignedLong`(unsigned long v)
  Return value: New reference.

  Return a new `PyLongObject` object from a C `unsigned long`, or NULL on failure.

PyObject* `PyLong_FromSsize_t`(Py_ssize_t v)

  Return a new `PyLongObject` object from a C `Py_ssize_t`, or NULL on failure.

PyObject* `PyLong_FromSize_t`(size_t v)

  Return a new `PyLongObject` object from a C `size_t`, or NULL on failure.

PyObject* `PyLong_FromLongLong`(long long v)
  Return value: New reference.

  Return a new `PyLongObject` object from a C `long long`, or NULL on failure.

PyObject* `PyLong_FromUnsignedLongLong`(unsigned long long v)
  Return value: New reference.

  Return a new `PyLongObject` object from a C `unsigned long long`, or NULL on failure.

PyObject* `PyLong_FromDouble`(double v)
  Return value: New reference.

  Return a new `PyLongObject` object from the integer part of v, or NULL on failure.

PyObject* `PyLong_FromString`(const char *str, char **pend, int base)
  Return value: New reference.

  Return a new `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 `'0o'` or `'0O'`, radix 8 will be used; if str starts with `'0b'` or `'0B'`, radix 2 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, `ValueError` will be raised.

PyObject* `PyLong_FromUnicode`( Py_UNICODE *u, Py_ssize_t length, int base)
  Return value: New reference.

  Convert a sequence of Unicode digits to a Python integer value. The Unicode string is first encoded to a byte string using `PyUnicode_EncodeDecimal()` and then converted using `PyLong_FromString()`.

  Deprecated since version 3.3, will be removed in version 4.0: Part of the old-style `Py_UNICODE` API; please migrate to using `PyLong_FromUnicodeObject()`.

PyObject* `PyLong_FromUnicodeObject`( PyObject *u, int base)

  Convert a sequence of Unicode digits in the string u to a Python integer value. The Unicode string is first encoded to a byte string using `PyUnicode_EncodeDecimal()` and then converted using `PyLong_FromString()`.

  New in version 3.3.

PyObject* `PyLong_FromVoidPtr`(void *p)
  Return value: New reference.

  Create a Python integer from the pointer p. The pointer value can be retrieved from the resulting value using `PyLong_AsVoidPtr()`.

long `PyLong_AsLong`( PyObject *obj)

  Return a C `long` representation of obj. If obj is not an instance of `PyLongObject`, first call its `__int__()` method (if present) to convert it to a `PyLongObject`.

  Raise `OverflowError` if the value of obj is out of range for a `long`.

long `PyLong_AsLongAndOverflow`( PyObject *obj, int *overflow)

  Return a C `long` representation of obj. If obj is not an instance of `PyLongObject`, first call its `__int__()` method (if present) to convert it to a `PyLongObject`.

  If the value of obj is greater than `LONG_MAX` or less than `LONG_MIN`, set *overflow to `1` or `-1`, respectively, and return `-1`; otherwise, set *overflow to `0`. If any other exception occurs set *overflow to `0` and return `-1` as usual.

long long `PyLong_AsLongLong`( PyObject *obj)

  Return a C `long long` representation of obj. If obj is not an instance of `PyLongObject`, first call its `__int__()` method (if present) to convert it to a `PyLongObject`.

  Raise `OverflowError` if the value of obj is out of range for a `long`.

long long `PyLong_AsLongLongAndOverflow`( PyObject *obj, int *overflow)

  Return a C `long long` representation of obj. If obj is not an instance of `PyLongObject`, first call its `__int__()` method (if present) to convert it to a `PyLongObject`.

  If the value of obj is greater than `PY_LLONG_MAX` or less than `PY_LLONG_MIN`, set *overflow to `1` or `-1`, respectively, and return `-1`; otherwise, set *overflow to `0`. If any other exception occurs set *overflow to `0` and return `-1` as usual.

  New in version 3.2.

Py_ssize_t `PyLong_AsSsize_t`( PyObject *pylong)

  Return a C `Py_ssize_t` representation of pylong. pylong must be an instance of `PyLongObject`.

  Raise `OverflowError` if the value of pylong is out of range for a `Py_ssize_t`.

unsigned long `PyLong_AsUnsignedLong`( PyObject *pylong)

  Return a C `unsigned long` representation of pylong. pylong must be an instance of `PyLongObject`.

  Raise `OverflowError` if the value of pylong is out of range for a `unsigned long`.

size_t `PyLong_AsSize_t`( PyObject *pylong)

  Return a C `size_t` representation of pylong. pylong must be an instance of `PyLongObject`.

  Raise `OverflowError` if the value of pylong is out of range for a `size_t`.

unsigned long long `PyLong_AsUnsignedLongLong`( PyObject *pylong)

  Return a C `unsigned long long` representation of pylong. pylong must be an instance of `PyLongObject`.

  Raise `OverflowError` if the value of pylong is out of range for an `unsigned long long`.

  Changed in version 3.1: A negative pylong now raises `OverflowError`, not `TypeError`.

unsigned long `PyLong_AsUnsignedLongMask`( PyObject *obj)

  Return a C `unsigned long` representation of obj. If obj is not an instance of `PyLongObject`, first call its `__int__()` method (if present) to convert it to a `PyLongObject`.

  If the value of obj is out of range for an `unsigned long`, return the reduction of that value modulo `ULONG_MAX + 1`.

unsigned long long `PyLong_AsUnsignedLongLongMask`( PyObject *obj)

  Return a C `unsigned long long` representation of obj. If obj is not an instance of `PyLongObject`, first call its `__int__()` method (if present) to convert it to a `PyLongObject`.

  If the value of obj is out of range for an `unsigned long long`, return the reduction of that value modulo `PY_ULLONG_MAX + 1`.

double `PyLong_AsDouble`( PyObject *pylong)

  Return a C `double` representation of pylong. pylong must be an instance of `PyLongObject`.

  Raise `OverflowError` if the value of pylong is out of range for a `double`.

void* `PyLong_AsVoidPtr`( PyObject *pylong)

  Convert a Python integer pylong to a C `void` pointer. If pylong cannot be converted, an `OverflowError` will be raised. This is only assured to produce a usable `void` pointer for values created with `PyLong_FromVoidPtr()`.