Mapping Protocol¶

See also PyObject_GetItem(), PyObject_SetItem() and 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.

Returns the number of keys in object o on success, and -1 on failure. This is equivalent to the Python expression 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.

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.

Note

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*.

Note

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.

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

Changed in version 3.7: Previously, the function returned a list or a tuple.

PyObject *PyMapping_Values(PyObject *o)¶

Return value: New reference. Part of the Stable ABI.

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

Changed in version 3.7: Previously, the function returned a list or a tuple.

PyObject *PyMapping_Items(PyObject *o)¶

Return value: New reference. Part of the Stable ABI.

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.

Changed in version 3.7: Previously, the function returned a list or a tuple.