字典对象 ¶

PyDictObject ¶

此子类型的 PyObject represents a Python dictionary object.

PyTypeObject PyDict_Type ¶

此实例的 PyTypeObject represents the Python dictionary type. This is exposed to Python programs as dict and types.DictType .

int PyDict_Check ( PyObject *p ) ¶

返回 True 若 p is a dict object or an instance of a subtype of the dict type.

2.2 版改变： Allowed subtypes to be accepted.

int PyDict_CheckExact ( PyObject *p ) ¶

返回 True 若 p is a dict object, but not an instance of a subtype of the dict type.

2.4 版新增。

PyObject * PyDict_New ( ) ¶

返回值：新引用。

Return a new empty dictionary, or NULL 当故障时。

PyObject * PyDictProxy_New ( PyObject *dict ) ¶

返回值：新引用。

Return a proxy object for a mapping which enforces read-only behavior. This is normally used to create a proxy to prevent modification of the dictionary for non-dynamic class types.

2.2 版新增。

void PyDict_Clear ( PyObject *p ) ¶

Empty an existing dictionary of all key-value pairs.

int PyDict_Contains ( PyObject *p , PyObject *key ) ¶

Determine if dictionary p 包含 key . If an item in p is matches key ，返回 1 ，否则返回 0 . On error, return -1 . This is equivalent to the Python expression key in p .

2.4 版新增。

PyObject * PyDict_Copy ( PyObject *p ) ¶

返回值：新引用。

Return a new dictionary that contains the same key-value pairs as p .

New in version 1.6.

int PyDict_SetItem ( PyObject *p , PyObject *key , PyObject *val ) ¶

插入 value into the dictionary p with a key of key . key 必须为 hashable ; if it isn’t, TypeError will be raised. Return 0 当成功时或 -1 当故障时。

int PyDict_SetItemString ( PyObject *p , const char *key , PyObject *val ) ¶

插入 value into the dictionary p 使用 key as a key. key 应该为 char* . The key object is created using PyString_FromString(key) 。返回 0 当成功时或 -1 当故障时。

int PyDict_DelItem ( PyObject *p , PyObject *key ) ¶

Remove the entry in dictionary p 采用键 key . key must be hashable; if it isn’t, TypeError is raised. Return 0 当成功时或 -1 当故障时。

int PyDict_DelItemString ( PyObject *p , char *key ) ¶

Remove the entry in dictionary p which has a key specified by the string key 。返回 0 当成功时或 -1 当故障时。

PyObject * PyDict_GetItem ( PyObject *p , PyObject *key ) ¶

返回值：借位引用。

Return the object from dictionary p which has a key key 。返回 NULL if the key key is not present, but without setting an exception.

PyObject * PyDict_GetItemString ( PyObject *p , const char *key ) ¶

返回值：借位引用。

这如同 PyDict_GetItem() ，但 key is specified as a char* , rather than a PyObject* .

PyObject * PyDict_Items ( PyObject *p ) ¶

返回值：新引用。

返回 PyListObject containing all the items from the dictionary, as in the dictionary method dict.items() .

PyObject * PyDict_Keys ( PyObject *p ) ¶

返回值：新引用。

返回 PyListObject containing all the keys from the dictionary, as in the dictionary method dict.keys() .

PyObject * PyDict_Values ( PyObject *p ) ¶

返回值：新引用。

返回 PyListObject containing all the values from the dictionary p , as in the dictionary method dict.values() .

Py_ssize_t PyDict_Size ( PyObject *p ) ¶

Return the number of items in the dictionary. This is equivalent to len(p) on a dictionary.

Changed in version 2.5: This function returned an int type. This might require changes in your code for properly supporting 64-bit systems.

int PyDict_Next ( PyObject *p , Py_ssize_t *ppos , PyObject **pkey , PyObject **pvalue ) ¶

Iterate over all key-value pairs in the dictionary p 。 Py_ssize_t referred to by ppos must be initialized to 0 prior to the first call to this function to start the iteration; the function returns true for each pair in the dictionary, and false once all pairs have been reported. The parameters pkey and pvalue should either point to PyObject* variables that will be filled in with each key and value, respectively, or may be NULL . Any references returned through them are borrowed. ppos should not be altered during iteration. Its value represents offsets within the internal dictionary structure, and since the structure is sparse, the offsets are not consecutive.

例如：

PyObject *key, *value;
Py_ssize_t pos = 0;
while (PyDict_Next(self->dict, &pos, &key, &value)) {
    /* do something interesting with the values... */
    ...
}
						

The dictionary p should not be mutated during iteration. It is safe (since Python 2.1) to modify the values of the keys as you iterate over the dictionary, but only so long as the set of keys does not change. For example:

PyObject *key, *value;
Py_ssize_t pos = 0;
while (PyDict_Next(self->dict, &pos, &key, &value)) {
    int i = PyInt_AS_LONG(value) + 1;
    PyObject *o = PyInt_FromLong(i);
    if (o == NULL)
        return -1;
    if (PyDict_SetItem(self->dict, key, o) < 0) {
        Py_DECREF(o);
        return -1;
    }
    Py_DECREF(o);
}
						

Changed in version 2.5: This function used an int * type for ppos . This might require changes in your code for properly supporting 64-bit systems.

int PyDict_Merge ( PyObject *a , PyObject *b , int override ) ¶

Iterate over mapping object b adding key-value pairs to dictionary a . b may be a dictionary, or any object supporting PyMapping_Keys() and PyObject_GetItem() 。若 override is true, existing pairs in a will be replaced if a matching key is found in b , otherwise pairs will only be added if there is not a matching key in a 。返回 0 当成功时或 -1 if an exception was raised.

2.2 版新增。

int PyDict_Update ( PyObject *a , PyObject *b ) ¶

这如同 PyDict_Merge(a, b, 1) in C, and is similar to a.update(b) in Python except that PyDict_Update() doesn’t fall back to the iterating over a sequence of key value pairs if the second argument has no “keys” attribute. Return 0 当成功时或 -1 if an exception was raised.

2.2 版新增。

int PyDict_MergeFromSeq2 ( PyObject *a , PyObject *seq2 , int override ) ¶

Update or merge into dictionary a , from the key-value pairs in seq2 . seq2 must be an iterable object producing iterable objects of length 2, viewed as key-value pairs. In case of duplicate keys, the last wins if override is true, else the first wins. Return 0 当成功时或 -1 if an exception was raised. Equivalent Python (except for the return value):

def PyDict_MergeFromSeq2(a, seq2, override):
    for key, value in seq2:
        if override or key not in a:
            a[key] = value
						

2.2 版新增。

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