# Protocolo de mapeo

Consulte también `PyObject_GetItem()`, `PyObject_SetItem()` y `PyObject_DelItem()`.

int PyMapping_Check(PyObject *o)
  Part of the Stable ABI.

  Return `1` if the object provides the mapping protocol or supports slicing, and `0` otherwise. Note that it returns `1` for Python classes with a `__getitem__()` method, since in general it is impossible to determine what type of keys the class supports. This function always succeeds.

Py_ssize_t PyMapping_Size(PyObject *o)
Py_ssize_t PyMapping_Length(PyObject *o)
  Part of the Stable ABI.

  Retorna el número de claves en el objeto o en caso de éxito, y `-1` en caso de error. Esto es equivalente a la expresión de Python `len(o)`.

PyObject *PyMapping_GetItemString(PyObject *o, const char *key)
  Return value: New reference. Part of the Stable ABI.

  This is the same as `PyObject_GetItem()`, but key is specified as a const char* UTF-8 encoded bytes string, rather than a PyObject*.

int PyMapping_GetOptionalItem(PyObject *obj, PyObject *key, PyObject **result)
  Part of the Stable ABI since version 3.13.

  Variant of `PyObject_GetItem()` which doesn’t raise `KeyError` if the key is not found.

  If the key is found, return `1` and set *result to a new strong reference to the corresponding value. If the key is not found, return `0` and set *result to `NULL`; the `KeyError` is silenced. If an error other than `KeyError` is raised, return `-1` and set *result to `NULL`.

  Added in version 3.13.

int PyMapping_GetOptionalItemString(PyObject *obj, const char *key, PyObject **result)
  Part of the Stable ABI since version 3.13.

  This is the same as `PyMapping_GetOptionalItem()`, but key is specified as a const char* UTF-8 encoded bytes string, rather than a PyObject*.

  Added in version 3.13.

int PyMapping_SetItemString(PyObject *o, const char *key, PyObject *v)
  Part of the Stable ABI.

  This is the same as `PyObject_SetItem()`, but key is specified as a const char* UTF-8 encoded bytes string, rather than a PyObject*.

int PyMapping_DelItem(PyObject *o, PyObject *key)

  This is an alias of `PyObject_DelItem()`.

int PyMapping_DelItemString(PyObject *o, const char *key)

  This is the same as `PyObject_DelItem()`, but key is specified as a const char* UTF-8 encoded bytes string, rather than a PyObject*.

int PyMapping_HasKeyWithError(PyObject *o, PyObject *key)
  Part of the Stable ABI since version 3.13.

  Return `1` if the mapping object has the key key and `0` otherwise. This is equivalent to the Python expression `key in o`. On failure, return `-1`.

  Added in version 3.13.

int PyMapping_HasKeyStringWithError(PyObject *o, const char *key)
  Part of the Stable ABI since version 3.13.

  This is the same as `PyMapping_HasKeyWithError()`, but key is specified as a const char* UTF-8 encoded bytes string, rather than a PyObject*.

  Added in version 3.13.

int PyMapping_HasKey(PyObject *o, PyObject *key)
  Part of the Stable ABI.

  Retorna `1` si el objeto de mapeo tiene la clave key y `0` de lo contrario. Esto es equivalente a la expresión de Python `key in o`. Esta función siempre finaliza con éxito.

  Nota

  Exceptions which occur when this calls the `__getitem__()` method are silently ignored. For proper error handling, use `PyMapping_HasKeyWithError()`, `PyMapping_GetOptionalItem()` or `PyObject_GetItem()` instead.

int PyMapping_HasKeyString(PyObject *o, const char *key)
  Part of the Stable ABI.

  This is the same as `PyMapping_HasKey()`, but key is specified as a const char* UTF-8 encoded bytes string, rather than a PyObject*.

  Nota

  Exceptions that occur when this calls the `__getitem__()` method or while creating the temporary `str` object are silently ignored. For proper error handling, use `PyMapping_HasKeyStringWithError()`, `PyMapping_GetOptionalItemString()` or `PyMapping_GetItemString()` instead.

PyObject *PyMapping_Keys(PyObject *o)
  Return value: New reference. Part of the Stable ABI.

  En caso de éxito, retorna una lista de las claves en el objeto o. En caso de fallo, retorna `NULL`.

  Distinto en la versión 3.7: Anteriormente, la función retornaba una lista o una tupla.

PyObject *PyMapping_Values(PyObject *o)
  Return value: New reference. Part of the Stable ABI.

  En caso de éxito, retorna una lista de los valores en el objeto o. En caso de fallo, retorna `NULL`.

  Distinto en la versión 3.7: Anteriormente, la función retornaba una lista o una tupla.

PyObject *PyMapping_Items(PyObject *o)
  Return value: New reference. Part of the Stable ABI.

  En caso de éxito, retorna una lista de los elementos en el objeto o, donde cada elemento es una tupla que contiene un par clave-valor (key-value). En caso de fallo, retorna `NULL`.

  Distinto en la versión 3.7: Anteriormente, la función retornaba una lista o una tupla.