1.. highlightlang:: c 2 3.. _mapping: 4 5Mapping Protocol 6================ 7 8 9.. c:function:: int PyMapping_Check(PyObject *o) 10 11 Return ``1`` if the object provides mapping protocol, and ``0`` otherwise. This 12 function always succeeds. 13 14 15.. c:function:: Py_ssize_t PyMapping_Size(PyObject *o) 16 Py_ssize_t PyMapping_Length(PyObject *o) 17 18 .. index:: builtin: len 19 20 Returns the number of keys in object *o* on success, and ``-1`` on failure. For 21 objects that do not provide mapping protocol, this is equivalent to the Python 22 expression ``len(o)``. 23 24 .. versionchanged:: 2.5 25 These functions returned an :c:type:`int` type. This might require 26 changes in your code for properly supporting 64-bit systems. 27 28 29.. c:function:: int PyMapping_DelItemString(PyObject *o, char *key) 30 31 Remove the mapping for object *key* from the object *o*. Return ``-1`` on 32 failure. This is equivalent to the Python statement ``del o[key]``. 33 34 35.. c:function:: int PyMapping_DelItem(PyObject *o, PyObject *key) 36 37 Remove the mapping for object *key* from the object *o*. Return ``-1`` on 38 failure. This is equivalent to the Python statement ``del o[key]``. 39 40 41.. c:function:: int PyMapping_HasKeyString(PyObject *o, char *key) 42 43 On success, return ``1`` if the mapping object has the key *key* and ``0`` 44 otherwise. This is equivalent to ``o[key]``, returning ``True`` on success 45 and ``False`` on an exception. This function always succeeds. 46 47 48.. c:function:: int PyMapping_HasKey(PyObject *o, PyObject *key) 49 50 Return ``1`` if the mapping object has the key *key* and ``0`` otherwise. 51 This is equivalent to ``o[key]``, returning ``True`` on success and ``False`` 52 on an exception. This function always succeeds. 53 54 55.. c:function:: PyObject* PyMapping_Keys(PyObject *o) 56 57 On success, return a list of the keys in object *o*. On failure, return *NULL*. 58 This is equivalent to the Python expression ``o.keys()``. 59 60 61.. c:function:: PyObject* PyMapping_Values(PyObject *o) 62 63 On success, return a list of the values in object *o*. On failure, return 64 *NULL*. This is equivalent to the Python expression ``o.values()``. 65 66 67.. c:function:: PyObject* PyMapping_Items(PyObject *o) 68 69 On success, return a list of the items in object *o*, where each item is a tuple 70 containing a key-value pair. On failure, return *NULL*. This is equivalent to 71 the Python expression ``o.items()``. 72 73 74.. c:function:: PyObject* PyMapping_GetItemString(PyObject *o, char *key) 75 76 Return element of *o* corresponding to the object *key* or *NULL* on failure. 77 This is the equivalent of the Python expression ``o[key]``. 78 79 80.. c:function:: int PyMapping_SetItemString(PyObject *o, char *key, PyObject *v) 81 82 Map the object *key* to the value *v* in object *o*. Returns ``-1`` on failure. 83 This is the equivalent of the Python statement ``o[key] = v``. 84