Objetos enteros
***************

Todos los enteros se implementan como objetos enteros "largos"
(*long*) de tamaño arbitrario.

En caso de error, la mayoría de las API "PyLong_As*" retornan "(tipo
de retorno) -1" que no se puede distinguir de un número. Use
"PyErr_Occurred()" para desambiguar.

type PyLongObject
    * Part of the Limited API (as an opaque struct).*

   Este subtipo de "PyObject" representa un objeto entero de Python.

PyTypeObject PyLong_Type
    * Part of the Stable ABI.*

   Esta instancia de "PyTypeObject" representa el tipo entero de
   Python. Este es el mismo objeto que "int" en la capa de Python.

int PyLong_Check(PyObject *p)

   Retorna verdadero si su argumento es un "PyLongObject" o un subtipo
   de "PyLongObject". Esta función siempre finaliza con éxito.

int PyLong_CheckExact(PyObject *p)

   Retorna verdadero si su argumento es un "PyLongObject", pero no un
   subtipo de "PyLongObject". Esta función siempre finaliza con éxito.

PyObject *PyLong_FromLong(long v)
    *Return value: New reference.** Part of the Stable ABI.*

   Retorna un objeto "PyLongObject" nuevo desde *v*, o "NULL" en caso
   de error.

   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.

PyObject *PyLong_FromUnsignedLong(unsigned long v)
    *Return value: New reference.** Part of the Stable ABI.*

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

PyObject *PyLong_FromSsize_t(Py_ssize_t v)
    *Return value: New reference.** Part of the Stable ABI.*

   Retorna un objeto "PyLongObject" nuevo desde un C "Py_ssize_t", o
   "NULL" en caso de error.

PyObject *PyLong_FromSize_t(size_t v)
    *Return value: New reference.** Part of the Stable ABI.*

   Retorna un objeto "PyLongObject" nuevo desde un C "size_t", o
   "NULL" en caso de error.

PyObject *PyLong_FromLongLong(long long v)
    *Return value: New reference.** Part of the Stable ABI.*

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

PyObject *PyLong_FromInt32(int32_t value)
PyObject *PyLong_FromInt64(int64_t value)
    * Part of the Stable ABI since version 3.14.*

   Return a new "PyLongObject" object from a signed C int32_t or
   int64_t, or "NULL" with an exception set on failure.

   Added in version 3.14.

PyObject *PyLong_FromUnsignedLongLong(unsigned long long v)
    *Return value: New reference.** Part of the Stable ABI.*

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

PyObject *PyLong_FromUInt32(uint32_t value)
PyObject *PyLong_FromUInt64(uint64_t value)
    * Part of the Stable ABI since version 3.14.*

   Return a new "PyLongObject" object from an unsigned C uint32_t or
   uint64_t, or "NULL" with an exception set on failure.

   Added in version 3.14.

PyObject *PyLong_FromDouble(double v)
    *Return value: New reference.** Part of the Stable ABI.*

   Retorna un nuevo objeto "PyLongObject" de la parte entera de *v*, o
   "NULL" en caso de error.

PyObject *PyLong_FromString(const char *str, char **pend, int base)
    *Return value: New reference.** Part of the Stable ABI.*

   Return a new "PyLongObject" based on the string value in *str*,
   which is interpreted according to the radix in *base*, or "NULL" on
   failure.  If *pend* is non-"NULL", **pend* will point to the end of
   *str* on success or to the first character that could not be
   processed on error.  If *base* is "0", *str* is interpreted using
   the Literales enteros definition; in this case, leading zeros in a
   non-zero decimal number raises a "ValueError".  If *base* is not
   "0", it must be between "2" and "36", inclusive.  Leading and
   trailing whitespace and single underscores after a base specifier
   and between digits are ignored.  If there are no digits or *str* is
   not NULL-terminated following the digits and trailing whitespace,
   "ValueError" will be raised.

   Ver también:

     "PyLong_AsNativeBytes()" and "PyLong_FromNativeBytes()" functions
     can be used to convert a "PyLongObject" to/from an array of bytes
     in base "256".

PyObject *PyLong_FromUnicodeObject(PyObject *u, int base)
    *Return value: New reference.*

   Convierte una secuencia de dígitos Unicode en la cadena de
   caracteres *u* en un valor entero de Python.

   Added in version 3.3.

PyObject *PyLong_FromVoidPtr(void *p)
    *Return value: New reference.** Part of the Stable ABI.*

   Crea un entero de Python desde el puntero *p*. El valor del puntero
   se puede recuperar del valor resultante usando
   "PyLong_AsVoidPtr()".

PyObject *PyLong_FromNativeBytes(const void *buffer, size_t n_bytes, int flags)

   Create a Python integer from the value contained in the first
   *n_bytes* of *buffer*, interpreted as a two's-complement signed
   number.

   *flags* are as for "PyLong_AsNativeBytes()". Passing "-1" will
   select the native endian that CPython was compiled with and assume
   that the most-significant bit is a sign bit. Passing
   "Py_ASNATIVEBYTES_UNSIGNED_BUFFER" will produce the same result as
   calling "PyLong_FromUnsignedNativeBytes()". Other flags are
   ignored.

   Added in version 3.13.

PyObject *PyLong_FromUnsignedNativeBytes(const void *buffer, size_t n_bytes, int flags)

   Create a Python integer from the value contained in the first
   *n_bytes* of *buffer*, interpreted as an unsigned number.

   *flags* are as for "PyLong_AsNativeBytes()". Passing "-1" will
   select the native endian that CPython was compiled with and assume
   that the most-significant bit is not a sign bit. Flags other than
   endian are ignored.

   Added in version 3.13.

long PyLong_AsLong(PyObject *obj)
    * Part of the Stable ABI.*

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

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

   Retorna "-1" en caso de error. Use "PyErr_Occurred()" para
   desambiguar.

   Distinto en la versión 3.8: Use "__index__()" if available.

   Distinto en la versión 3.10: This function will no longer use
   "__int__()".

   long PyLong_AS_LONG(PyObject *obj)

      A *soft deprecated* alias. Exactly equivalent to the preferred
      "PyLong_AsLong". In particular, it can fail with "OverflowError"
      or another exception.

      Obsoleto desde la versión 3.14: The function is soft deprecated.

int PyLong_AsInt(PyObject *obj)
    * Part of the Stable ABI since version 3.13.*

   Similar to "PyLong_AsLong()", but store the result in a C int
   instead of a C long.

   Added in version 3.13.

long PyLong_AsLongAndOverflow(PyObject *obj, int *overflow)
    * Part of the Stable ABI.*

   Return a C long representation of *obj*.  If *obj* is not an
   instance of "PyLongObject", first call its "__index__()" 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.

   Retorna "-1" en caso de error. Use "PyErr_Occurred()" para
   desambiguar.

   Distinto en la versión 3.8: Use "__index__()" if available.

   Distinto en la versión 3.10: This function will no longer use
   "__int__()".

long long PyLong_AsLongLong(PyObject *obj)
    * Part of the Stable ABI.*

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

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

   Retorna "-1" en caso de error. Use "PyErr_Occurred()" para
   desambiguar.

   Distinto en la versión 3.8: Use "__index__()" if available.

   Distinto en la versión 3.10: This function will no longer use
   "__int__()".

long long PyLong_AsLongLongAndOverflow(PyObject *obj, int *overflow)
    * Part of the Stable ABI.*

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

   If the value of *obj* is greater than "LLONG_MAX" or less than
   "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.

   Retorna "-1" en caso de error. Use "PyErr_Occurred()" para
   desambiguar.

   Added in version 3.2.

   Distinto en la versión 3.8: Use "__index__()" if available.

   Distinto en la versión 3.10: This function will no longer use
   "__int__()".

Py_ssize_t PyLong_AsSsize_t(PyObject *pylong)
    * Part of the Stable ABI.*

   Retorna una representación de C "Py_ssize_t" de *pylong*. *pylong*
   debe ser una instancia de "PyLongObject".

   Lanza "OverflowError" si el valor de *pylong* está fuera de rango
   para un "Py_ssize_t".

   Retorna "-1" en caso de error. Use "PyErr_Occurred()" para
   desambiguar.

unsigned long PyLong_AsUnsignedLong(PyObject *pylong)
    * Part of the Stable ABI.*

   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.

   Retorna "(unsigned long)-1" en caso de error. Use
   "PyErr_Occurred()" para desambiguar.

size_t PyLong_AsSize_t(PyObject *pylong)
    * Part of the Stable ABI.*

   Retorna una representación de C "size_t" de *pylong*. *pylong* debe
   ser una instancia de "PyLongObject".

   Lanza "OverflowError" si el valor de *pylong* está fuera de rango
   para un "size_t".

   Retorna "(size_t) -1" en caso de error. Use "PyErr_Occurred()" para
   desambiguar.

unsigned long long PyLong_AsUnsignedLongLong(PyObject *pylong)
    * Part of the Stable ABI.*

   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.

   Retorna "(unsigned long long) -1" en caso de error. Use
   "PyErr_Occurred()" para desambiguar.

   Distinto en la versión 3.1: Ahora un *pylong* negativo lanza un
   "OverflowError", no "TypeError".

unsigned long PyLong_AsUnsignedLongMask(PyObject *obj)
    * Part of the Stable ABI.*

   Return a C unsigned long representation of *obj*.  If *obj* is not
   an instance of "PyLongObject", first call its "__index__()" 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".

   Retorna "(unsigned long)-1" en caso de error. Use
   "PyErr_Occurred()" para desambiguar.

   Distinto en la versión 3.8: Use "__index__()" if available.

   Distinto en la versión 3.10: This function will no longer use
   "__int__()".

unsigned long long PyLong_AsUnsignedLongLongMask(PyObject *obj)
    * Part of the Stable ABI.*

   Return a C unsigned long long representation of *obj*.  If *obj* is
   not an instance of "PyLongObject", first call its "__index__()"
   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 "ULLONG_MAX + 1".

   Retorna "(unsigned long long) -1" por error. Use "PyErr_Occurred()"
   para desambiguar.

   Distinto en la versión 3.8: Use "__index__()" if available.

   Distinto en la versión 3.10: This function will no longer use
   "__int__()".

int PyLong_AsInt32(PyObject *obj, int32_t *value)
int PyLong_AsInt64(PyObject *obj, int64_t *value)
    * Part of the Stable ABI since version 3.14.*

   Set **value* to a signed C int32_t or int64_t representation of
   *obj*.

   If the *obj* value is out of range, raise an "OverflowError".

   Set **value* and return "0" on success. Set an exception and return
   "-1" on error.

   *value* must not be "NULL".

   Added in version 3.14.

int PyLong_AsUInt32(PyObject *obj, uint32_t *value)
int PyLong_AsUInt64(PyObject *obj, uint64_t *value)
    * Part of the Stable ABI since version 3.14.*

   Set **value* to an unsigned C uint32_t or uint64_t representation
   of *obj*.

   If *obj* is not an instance of "PyLongObject", first call its
   "__index__()" method (if present) to convert it to a
   "PyLongObject".

   * If *obj* is negative, raise a "ValueError".

   * If the *obj* value is out of range, raise an "OverflowError".

   Set **value* and return "0" on success. Set an exception and return
   "-1" on error.

   *value* must not be "NULL".

   Added in version 3.14.

double PyLong_AsDouble(PyObject *pylong)
    * Part of the Stable ABI.*

   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.

   Retorna "-1.0" en caso de error. Use "PyErr_Occurred()" para
   desambiguar.

void *PyLong_AsVoidPtr(PyObject *pylong)
    * Part of the Stable ABI.*

   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()".

   Retorna "NULL" en caso de error. Use "PyErr_Occurred()" para
   desambiguar.

Py_ssize_t PyLong_AsNativeBytes(PyObject *pylong, void *buffer, Py_ssize_t n_bytes, int flags)

   Copy the Python integer value *pylong* to a native *buffer* of size
   *n_bytes*. The *flags* can be set to "-1" to behave similarly to a
   C cast, or to values documented below to control the behavior.

   Returns "-1" with an exception raised on error.  This may happen if
   *pylong* cannot be interpreted as an integer, or if *pylong* was
   negative and the "Py_ASNATIVEBYTES_REJECT_NEGATIVE" flag was set.

   Otherwise, returns the number of bytes required to store the value.
   If this is equal to or less than *n_bytes*, the entire value was
   copied. All *n_bytes* of the buffer are written: large buffers are
   padded with zeroes.

   If the returned value is greater than than *n_bytes*, the value was
   truncated: as many of the lowest bits of the value as could fit are
   written, and the higher bits are ignored. This matches the typical
   behavior of a C-style downcast.

   Nota:

     Overflow is not considered an error. If the returned value is
     larger than *n_bytes*, most significant bits were discarded.

   "0" will never be returned.

   Values are always copied as two's-complement.

   Usage example:

      int32_t value;
      Py_ssize_t bytes = PyLong_AsNativeBytes(pylong, &value, sizeof(value), -1);
      if (bytes < 0) {
          // Failed. A Python exception was set with the reason.
          return NULL;
      }
      else if (bytes <= (Py_ssize_t)sizeof(value)) {
          // Success!
      }
      else {
          // Overflow occurred, but 'value' contains the truncated
          // lowest bits of pylong.
      }

   Passing zero to *n_bytes* will return the size of a buffer that
   would be large enough to hold the value. This may be larger than
   technically necessary, but not unreasonably so. If *n_bytes=0*,
   *buffer* may be "NULL".

   Nota:

     Passing *n_bytes=0* to this function is not an accurate way to
     determine the bit length of the value.

   To get at the entire Python value of an unknown size, the function
   can be called twice: first to determine the buffer size, then to
   fill it:

      // Ask how much space we need.
      Py_ssize_t expected = PyLong_AsNativeBytes(pylong, NULL, 0, -1);
      if (expected < 0) {
          // Failed. A Python exception was set with the reason.
          return NULL;
      }
      assert(expected != 0);  // Impossible per the API definition.
      uint8_t *bignum = malloc(expected);
      if (!bignum) {
          PyErr_SetString(PyExc_MemoryError, "bignum malloc failed.");
          return NULL;
      }
      // Safely get the entire value.
      Py_ssize_t bytes = PyLong_AsNativeBytes(pylong, bignum, expected, -1);
      if (bytes < 0) {  // Exception has been set.
          free(bignum);
          return NULL;
      }
      else if (bytes > expected) {  // This should not be possible.
          PyErr_SetString(PyExc_RuntimeError,
              "Unexpected bignum truncation after a size check.");
          free(bignum);
          return NULL;
      }
      // The expected success given the above pre-check.
      // ... use bignum ...
      free(bignum);

   *flags* is either "-1" ("Py_ASNATIVEBYTES_DEFAULTS") to select
   defaults that behave most like a C cast, or a combination of the
   other flags in the table below. Note that "-1" cannot be combined
   with other flags.

   Currently, "-1" corresponds to "Py_ASNATIVEBYTES_NATIVE_ENDIAN |
   Py_ASNATIVEBYTES_UNSIGNED_BUFFER".

   +-----------------------------------------------+--------+
   | Flag                                          | Value  |
   |===============================================|========|
   | Py_ASNATIVEBYTES_DEFAULTS                     | "-1"   |
   +-----------------------------------------------+--------+
   | Py_ASNATIVEBYTES_BIG_ENDIAN                   | "0"    |
   +-----------------------------------------------+--------+
   | Py_ASNATIVEBYTES_LITTLE_ENDIAN                | "1"    |
   +-----------------------------------------------+--------+
   | Py_ASNATIVEBYTES_NATIVE_ENDIAN                | "3"    |
   +-----------------------------------------------+--------+
   | Py_ASNATIVEBYTES_UNSIGNED_BUFFER              | "4"    |
   +-----------------------------------------------+--------+
   | Py_ASNATIVEBYTES_REJECT_NEGATIVE              | "8"    |
   +-----------------------------------------------+--------+
   | Py_ASNATIVEBYTES_ALLOW_INDEX                  | "16"   |
   +-----------------------------------------------+--------+

   Specifying "Py_ASNATIVEBYTES_NATIVE_ENDIAN" will override any other
   endian flags. Passing "2" is reserved.

   By default, sufficient buffer will be requested to include a sign
   bit. For example, when converting 128 with *n_bytes=1*, the
   function will return 2 (or more) in order to store a zero sign bit.

   If "Py_ASNATIVEBYTES_UNSIGNED_BUFFER" is specified, a zero sign bit
   will be omitted from size calculations. This allows, for example,
   128 to fit in a single-byte buffer. If the destination buffer is
   later treated as signed, a positive input value may become
   negative. Note that the flag does not affect handling of negative
   values: for those, space for a sign bit is always requested.

   Specifying "Py_ASNATIVEBYTES_REJECT_NEGATIVE" causes an exception
   to be set if *pylong* is negative. Without this flag, negative
   values will be copied provided there is enough space for at least
   one sign bit, regardless of whether
   "Py_ASNATIVEBYTES_UNSIGNED_BUFFER" was specified.

   If "Py_ASNATIVEBYTES_ALLOW_INDEX" is specified and a non-integer
   value is passed, its "__index__()" method will be called first.
   This may result in Python code executing and other threads being
   allowed to run, which could cause changes to other objects or
   values in use. When *flags* is "-1", this option is not set, and
   non-integer values will raise "TypeError".

   Nota:

     With the default *flags* ("-1", or *UNSIGNED_BUFFER*  without
     *REJECT_NEGATIVE*), multiple Python integers can map to a single
     value without overflow. For example, both "255" and "-1" fit a
     single-byte buffer and set all its bits. This matches typical C
     cast behavior.

   Added in version 3.13.

int PyLong_GetSign(PyObject *obj, int *sign)

   Get the sign of the integer object *obj*.

   On success, set **sign* to the integer sign  (0, -1 or +1 for zero,
   negative or positive integer, respectively) and return 0.

   On failure, return -1 with an exception set.  This function always
   succeeds if *obj* is a "PyLongObject" or its subtype.

   Added in version 3.14.

int PyLong_IsPositive(PyObject *obj)

   Check if the integer object *obj* is positive ("obj > 0").

   If *obj* is an instance of "PyLongObject" or its subtype, return
   "1" when it's positive and "0" otherwise.  Else set an exception
   and return "-1".

   Added in version 3.14.0a1 (unreleased).

int PyLong_IsNegative(PyObject *obj)

   Check if the integer object *obj* is negative ("obj < 0").

   If *obj* is an instance of "PyLongObject" or its subtype, return
   "1" when it's negative and "0" otherwise.  Else set an exception
   and return "-1".

   Added in version 3.14.0a1 (unreleased).

int PyLong_IsZero(PyObject *obj)

   Check if the integer object *obj* is zero.

   If *obj* is an instance of "PyLongObject" or its subtype, return
   "1" when it's zero and "0" otherwise.  Else set an exception and
   return "-1".

   Added in version 3.14.0a1 (unreleased).

PyObject *PyLong_GetInfo(void)
    * Part of the Stable ABI.*

   On success, return a read only *named tuple*, that holds
   information about Python's internal representation of integers. See
   "sys.int_info" for description of individual fields.

   On failure, return "NULL" with an exception set.

   Added in version 3.1.

int PyUnstable_Long_IsCompact(const PyLongObject *op)

   *This is Unstable API. It may change without warning in minor
   releases.*

   Return 1 if *op* is compact, 0 otherwise.

   This function makes it possible for performance-critical code to
   implement a “fast path” for small integers. For compact values use
   "PyUnstable_Long_CompactValue()"; for others fall back to a
   "PyLong_As*" function or "PyLong_AsNativeBytes()".

   The speedup is expected to be negligible for most users.

   Exactly what values are considered compact is an implementation
   detail and is subject to change.

   Added in version 3.12.

Py_ssize_t PyUnstable_Long_CompactValue(const PyLongObject *op)

   *This is Unstable API. It may change without warning in minor
   releases.*

   If *op* is compact, as determined by "PyUnstable_Long_IsCompact()",
   return its value.

   Otherwise, the return value is undefined.

   Added in version 3.12.
