Integer Objects

Python 3.2.1

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(PY_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 PY_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(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().

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 *pylong)

Return a C long representation of the contents of pylong. If pylong is greater than LONG_MAX, raise an OverflowError, and return -1. Convert non-long objects automatically to long first, and return -1 if that raises exceptions.

long PyLong_AsLongAndOverflow(PyObject *pylong, int *overflow)

Return a C long representation of the contents of pylong. If pylong 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 (for example a TypeError or MemoryError), then -1 will be returned and *overflow will be 0.

PY_LONG_LONG PyLong_AsLongLongAndOverflow(PyObject *pylong, int *overflow)

Return a C long long representation of the contents of pylong. If pylong 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 (for example a TypeError or MemoryError), then -1 will be returned and *overflow will be 0.

New in version 3.2.

Py_ssize_t PyLong_AsSsize_t(PyObject *pylong)

Return a C Py_ssize_t representation of the contents of pylong. If pylong is greater than PY_SSIZE_T_MAX, an OverflowError is raised and -1 will be returned.

unsigned long PyLong_AsUnsignedLong(PyObject *pylong)

Return a C unsigned long representation of the contents of pylong. If pylong is greater than ULONG_MAX, an OverflowError is raised.

size_t PyLong_AsSize_t(PyObject *pylong)

Return a size_t representation of the contents of pylong. If pylong is greater than the maximum value for a size_t, an OverflowError is raised.

PY_LONG_LONG PyLong_AsLongLong(PyObject *pylong)

Return a C long long from a Python integer. If pylong cannot be represented as a long long, an OverflowError is raised and -1 is returned.

unsigned PY_LONG_LONG PyLong_AsUnsignedLongLong(PyObject *pylong)

Return a C unsigned long long from a Python integer. If pylong cannot be represented as an unsigned long long, an OverflowError is raised and (unsigned long long)-1 is returned.

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

unsigned long PyLong_AsUnsignedLongMask(PyObject *io)

Return a C unsigned long from a Python integer, without checking for overflow.

unsigned PY_LONG_LONG PyLong_AsUnsignedLongLongMask(PyObject *io)

Return a C unsigned long long from a Python integer, without checking for overflow.

double PyLong_AsDouble(PyObject *pylong)

Return a C double representation of the contents of pylong. If pylong cannot be approximately represented as a double, an OverflowError exception is raised and -1.0 will be returned.

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().