.. highlightlang:: c .. _mapping: Mapping Protocol ================ .. cfunction:: int PyMapping_Check(PyObject *o) Return ``1`` if the object provides mapping protocol, and ``0`` otherwise. This function always succeeds. .. cfunction:: Py_ssize_t PyMapping_Length(PyObject *o) .. index:: builtin: len 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)``. .. cfunction:: int PyMapping_DelItemString(PyObject *o, 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]``. .. cfunction:: 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]``. .. cfunction:: int PyMapping_HasKeyString(PyObject *o, char *key) On success, return ``1`` if the mapping object has the key *key* and ``0`` otherwise. This is equivalent to ``o[key]``, returning ``True`` on success and ``False`` on an exception. This function always succeeds. .. cfunction:: int PyMapping_HasKey(PyObject *o, PyObject *key) Return ``1`` if the mapping object has the key *key* and ``0`` otherwise. This is equivalent to ``o[key]``, returning ``True`` on success and ``False`` on an exception. This function always succeeds. .. cfunction:: PyObject* PyMapping_Keys(PyObject *o) On success, return a list of the keys in object *o*. On failure, return *NULL*. This is equivalent to the Python expression ``o.keys()``. .. cfunction:: PyObject* PyMapping_Values(PyObject *o) On success, return a list of the values in object *o*. On failure, return *NULL*. This is equivalent to the Python expression ``o.values()``. .. cfunction:: PyObject* PyMapping_Items(PyObject *o) On success, return a list of the items in object *o*, where each item is a tuple containing a key-value pair. On failure, return *NULL*. This is equivalent to the Python expression ``o.items()``. .. cfunction:: PyObject* PyMapping_GetItemString(PyObject *o, char *key) Return element of *o* corresponding to the object *key* or *NULL* on failure. This is the equivalent of the Python expression ``o[key]``. .. cfunction:: int PyMapping_SetItemString(PyObject *o, 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``.