字典物件
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PyDictObject

   "PyObject" 子型態代表一個 Python 字典物件。

PyTypeObject PyDict_Type

   This instance of "PyTypeObject" represents the Python dictionary
   type.  This is exposed to Python programs as "dict" and
   "types.DictType".

int PyDict_Check(PyObject *p)

   若 *p* 是一個字典物件或字典的子型態實例則會回傳 true。

   2.2 版更變: Allowed subtypes to be accepted.

int PyDict_CheckExact(PyObject *p)

   若 *p* 是一個字典物件但並不是一個字典子型態的實例，則回傳 true。

   2.4 版新加入.

PyObject* PyDict_New()
    *Return value: New reference.*

   回傳一個新的空字典，或在失敗時回傳 *NULL*。

PyObject* PyDictProxy_New(PyObject *dict)
    *Return value: New reference.*

   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 版新加入.

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* contains *key*.  If an item in *p* is
   matches *key*, return "1", otherwise return "0".  On error, return
   "-1". This is equivalent to the Python expression "key in p".

   2.4 版新加入.

PyObject* PyDict_Copy(PyObject *p)
    *Return value: New reference.*

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

   1.6 版新加入.

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

   Insert *value* into the dictionary *p* with a key of *key*.  *key*
   must be *hashable*; if it isn’t, "TypeError" will be raised. Return
   "0" on success or "-1" on failure.

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

   Insert *value* into the dictionary *p* using *key* as a key. *key*
   should be a "char*".  The key object is created using
   "PyString_FromString(key)".  Return "0" on success or "-1" on
   failure.

int PyDict_DelItem(PyObject *p, PyObject *key)

   Remove the entry in dictionary *p* with key *key*. *key* must be
   hashable; if it isn’t, "TypeError" is raised.  Return "0" on
   success or "-1" on failure.

int PyDict_DelItemString(PyObject *p, char *key)

   Remove the entry in dictionary *p* which has a key specified by the
   string *key*.  Return "0" on success or "-1" on failure.

PyObject* PyDict_GetItem(PyObject *p, PyObject *key)
    *Return value: Borrowed reference.*

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

PyObject* PyDict_GetItemString(PyObject *p, const char *key)
    *Return value: Borrowed reference.*

   This is the same as "PyDict_GetItem()", but *key* is specified as a
   "char*", rather than a "PyObject*".

PyObject* PyDict_Items(PyObject *p)
    *Return value: New reference.*

   Return a "PyListObject" containing all the items from the
   dictionary, as in the dictionary method "dict.items()".

PyObject* PyDict_Keys(PyObject *p)
    *Return value: New reference.*

   Return a "PyListObject" containing all the keys from the
   dictionary, as in the dictionary method "dict.keys()".

PyObject* PyDict_Values(PyObject *p)
    *Return value: New reference.*

   Return a "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.

   2.5 版更變: 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*.  The
   "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.

   For example:

      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);
      }

   2.5 版更變: 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()". If *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*. Return "0" on success or "-1" if an exception
   was raised.

   2.2 版新加入.

int PyDict_Update(PyObject *a, PyObject *b)

   This is the same as "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" on success
   or "-1" if an exception was raised.

   2.2 版新加入.

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" on success or "-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 版新加入.
