# Mapping Protocol

int `PyMapping_Check`( PyObject *o)

  Return `1` if the object provides mapping protocol, and `0` otherwise. This function always succeeds.

Py_ssize_t `PyMapping_Size`( PyObject *o)
Py_ssize_t `PyMapping_Length`( PyObject *o)

  Returns the number of keys in object o on success, and `-1` on failure. For objects that do not provide mapping protocol, this is equivalent to the Python expression `len(o)`.

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

  Remove the mapping for object key from the object o. Return `-1` on failure. This is equivalent to the Python statement `del o[key]`.

int `PyMapping_DelItem`( PyObject *o, PyObject *key)

  Remove the mapping for object key from the object o. Return `-1` on failure. This is equivalent to the Python statement `del o[key]`.

int `PyMapping_HasKeyString`( PyObject *o, const char *key)

  On success, return `1` if the mapping object has the key key and `0` otherwise. This is equivalent to the Python expression `key in o`. This function always succeeds.

int `PyMapping_HasKey`( PyObject *o, PyObject *key)

  Return `1` if the mapping object has the key key and `0` otherwise. This is equivalent to the Python expression `key in o`. This function always succeeds.

PyObject* `PyMapping_Keys`( PyObject *o)
  Return value: New reference.

  On success, return a list or tuple of the keys in object o. On failure, return NULL.

PyObject* `PyMapping_Values`( PyObject *o)
  Return value: New reference.

  On success, return a list or tuple of the values in object o. On failure, return NULL.

PyObject* `PyMapping_Items`( PyObject *o)
  Return value: New reference.

  On success, return a list or tuple of the items in object o, where each item is a tuple containing a key-value pair. On failure, return NULL.

PyObject* `PyMapping_GetItemString`( PyObject *o, const char *key)
  Return value: New reference.

  Return element of o corresponding to the object key or NULL on failure. This is the equivalent of the Python expression `o[key]`.

int `PyMapping_SetItemString`( PyObject *o, const char *key, PyObject *v)

  Map the object key to the value v in object o. Returns `-1` on failure. This is the equivalent of the Python statement `o[key] = v`.