# 딕셔너리 객체

type PyDictObject

  이 `PyObject`의 서브 형은 파이썬 딕셔너리 객체를 나타냅니다.

PyTypeObject PyDict_Type
  Part of the Stable ABI.

  이 `PyTypeObject` 인스턴스는 파이썬 딕셔너리 형을 나타냅니다. 이것은 파이썬 계층의 `dict`와 같은 객체입니다.

int PyDict_Check( PyObject *p)

  p가 dict 객체이거나 dict 형의 서브 형의 인스턴스면 참을 반환합니다. 이 함수는 항상 성공합니다.

int PyDict_CheckExact( PyObject *p)

  p가 dict 객체이지만, dict 형의 서브 형의 인스턴스는 아니면 참을 반환합니다. 이 함수는 항상 성공합니다.

PyObject *PyDict_New()
  Return value: New reference. Part of the Stable ABI.

  새로운 빈 딕셔너리를 반환하거나, 실패하면 `NULL`을 반환합니다.

PyObject *PyDictProxy_New( PyObject *mapping)
  Return value: New reference. Part of the Stable ABI.

  읽기 전용 동작을 강제하는 매핑을 위한 `types.MappingProxyType` 객체를 반환합니다. 이것은 일반적으로 비 동적 클래스 형을 위한 딕셔너리의 수정을 방지하기 위해 뷰를 만드는 데 사용됩니다.

void PyDict_Clear( PyObject *p)
  Part of the Stable ABI.

  기존 딕셔너리의 모든 키-값 쌍을 비웁니다.

int PyDict_Contains( PyObject *p, PyObject *key)
  Part of the Stable ABI.

  딕셔너리 p에 key가 포함되어 있는지 확인합니다. p의 항목이 key와 일치하면 `1`을 반환하고, 그렇지 않으면 `0`을 반환합니다. 에러면 `-1`을 반환합니다. 이는 파이썬 표현식 `key in p`와 동등합니다.

int PyDict_ContainsString( PyObject *p, const char *key)

  This is the same as `PyDict_Contains()`, but key is specified as a const char* UTF-8 encoded bytes string, rather than a PyObject *.

  Added in version 3.13.

PyObject *PyDict_Copy( PyObject *p)
  Return value: New reference. Part of the Stable ABI.

  p와 같은 키-값 쌍을 포함하는 새 딕셔너리를 반환합니다.

int PyDict_SetItem( PyObject *p, PyObject *key, PyObject *val)
  Part of the Stable ABI.

  딕셔너리 p에 val을 key 키로 삽입합니다. key는 해시 가능해야 합니다. 그렇지 않으면 `TypeError`가 발생합니다. 성공하면 `0`을, 실패하면 `-1`을 반환합니다. 이 함수는 val에 대한 참조를 훔치지 않습니다.

int PyDict_SetItemString( PyObject *p, const char *key, PyObject *val)
  Part of the Stable ABI.

  This is the same as `PyDict_SetItem()`, but key is specified as a const char* UTF-8 encoded bytes string, rather than a PyObject *.

int PyDict_DelItem( PyObject *p, PyObject *key)
  Part of the Stable ABI.

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

int PyDict_DelItemString( PyObject *p, const char *key)
  Part of the Stable ABI.

  This is the same as `PyDict_DelItem()`, but key is specified as a const char* UTF-8 encoded bytes string, rather than a PyObject *.

int PyDict_GetItemRef( PyObject *p, PyObject *key, PyObject **result)
  Part of the Stable ABI since version 3.13.

  Return a new strong reference to the object from dictionary p which has a key key:

  - If the key is present, set *result to a new strong reference to the value and return `1`.

  - If the key is missing, set *result to `NULL` and return `0`.

  - On error, raise an exception and return `-1`.

  Added in version 3.13.

  See also the `PyObject_GetItem()` function.

PyObject *PyDict_GetItem( PyObject *p, PyObject *key)
  Return value: Borrowed reference. Part of the Stable ABI.

  Return a borrowed reference to the object from dictionary p which has a key key. Return `NULL` if the key key is missing without setting an exception.

  참고

  Exceptions that occur while this calls `__hash__()` and `__eq__()` methods are silently ignored. Prefer the `PyDict_GetItemWithError()` function instead.

  버전 3.10에서 변경: Calling this API without GIL held had been allowed for historical reason. It is no longer allowed.

PyObject *PyDict_GetItemWithError( PyObject *p, PyObject *key)
  Return value: Borrowed reference. Part of the Stable ABI.

  예외를 억제하지 않는 `PyDict_GetItem()`의 변형입니다. 예외가 발생하면 예외를 설정하고 `NULL`을 반환합니다. 키가 없으면 예외를 설정하지 않고 `NULL`을 반환합니다.

PyObject *PyDict_GetItemString( PyObject *p, const char *key)
  Return value: Borrowed reference. Part of the Stable ABI.

  This is the same as `PyDict_GetItem()`, but key is specified as a const char* UTF-8 encoded bytes string, rather than a PyObject *.

  참고

  Exceptions that occur while this calls `__hash__()` and `__eq__()` methods or while creating the temporary `str` object are silently ignored. Prefer using the `PyDict_GetItemWithError()` function with your own `PyUnicode_FromString()` key instead.

int PyDict_GetItemStringRef( PyObject *p, const char *key, PyObject **result)
  Part of the Stable ABI since version 3.13.

  Similar to `PyDict_GetItemRef()`, but key is specified as a const char* UTF-8 encoded bytes string, rather than a PyObject *.

  Added in version 3.13.

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

  이것은 파이썬 수준의 `dict.setdefault()`와 같습니다. 존재하면, 딕셔너리 p에서 key에 해당하는 값을 반환합니다. 키가 dict에 없으면, 값 defaultobj로 삽입되고, defaultobj가 반환됩니다. 이 함수는 key의 해시 함수를 조회 및 삽입을 위해 독립적으로 평가하는 대신 한 번만 평가합니다.

  Added in version 3.4.

int PyDict_SetDefaultRef( PyObject *p, PyObject *key, PyObject *default_value, PyObject **result)

  Inserts default_value into the dictionary p with a key of key if the key is not already present in the dictionary. If result is not `NULL`, then *result is set to a strong reference to either default_value, if the key was not present, or the existing value, if key was already present in the dictionary. Returns `1` if the key was present and default_value was not inserted, or `0` if the key was not present and default_value was inserted. On failure, returns `-1`, sets an exception, and sets `*result` to `NULL`.

  For clarity: if you have a strong reference to default_value before calling this function, then after it returns, you hold a strong reference to both default_value and *result (if it’s not `NULL`). These may refer to the same object: in that case you hold two separate references to it.

  Added in version 3.13.

int PyDict_Pop( PyObject *p, PyObject *key, PyObject **result)

  Remove key from dictionary p and optionally return the removed value. Do not raise `KeyError` if the key missing.

  - If the key is present, set *result to a new reference to the removed value if result is not `NULL`, and return `1`.

  - If the key is missing, set *result to `NULL` if result is not `NULL`, and return `0`.

  - On error, raise an exception and return `-1`.

  Similar to `dict.pop()`, but without the default value and not raising `KeyError` if the key missing.

  Added in version 3.13.

int PyDict_PopString( PyObject *p, const char *key, PyObject **result)

  Similar to `PyDict_Pop()`, but key is specified as a const char* UTF-8 encoded bytes string, rather than a PyObject *.

  Added in version 3.13.

PyObject *PyDict_Items( PyObject *p)
  Return value: New reference. Part of the Stable ABI.

  딕셔너리의 모든 항목을 포함하는 `PyListObject`를 반환합니다.

PyObject *PyDict_Keys( PyObject *p)
  Return value: New reference. Part of the Stable ABI.

  딕셔너리의 모든 키를 포함하는 `PyListObject`를 반환합니다.

PyObject *PyDict_Values( PyObject *p)
  Return value: New reference. Part of the Stable ABI.

  딕셔너리 p의 모든 값을 포함하는 `PyListObject`를 반환합니다.

Py_ssize_t PyDict_Size( PyObject *p)
  Part of the Stable ABI.

  딕셔너리에 있는 항목의 수를 반환합니다. 이는 딕셔너리에 대한 `len(p)`와 동등합니다.

int PyDict_Next( PyObject *p, Py_ssize_t *ppos, PyObject **pkey, PyObject **pvalue)
  Part of the Stable ABI.

  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.

  예를 들면:

      PyObject *key, *value;
      Py_ssize_t pos = 0;

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

  딕셔너리 p는 이터레이션 중에 변경해서는 안 됩니다. 딕셔너리를 이터레이트 할 때 값을 변경하는 것은 안전하지만, 키 집합이 변경되지 않는 한만 그렇습니다. 예를 들면:

      PyObject *key, *value;
      Py_ssize_t pos = 0;

      while (PyDict_Next(self->dict, &pos, &key, &value)) {
          long i = PyLong_AsLong(value);
          if (i == -1 && PyErr_Occurred()) {
              return -1;
          }
          PyObject *o = PyLong_FromLong(i + 1);
          if (o == NULL)
              return -1;
          if (PyDict_SetItem(self->dict, key, o) < 0) {
              Py_DECREF(o);
              return -1;
          }
          Py_DECREF(o);
      }

  The function is not thread-safe in the free-threaded build without external synchronization. You can use `Py_BEGIN_CRITICAL_SECTION` to lock the dictionary while iterating over it:

      Py_BEGIN_CRITICAL_SECTION(self->dict);
      while (PyDict_Next(self->dict, &pos, &key, &value)) {
          ...
      }
      Py_END_CRITICAL_SECTION();

int PyDict_Merge( PyObject *a, PyObject *b, int override)
  Part of the Stable ABI.

  매핑 객체 b를 이터레이트 하면서, 키-값 쌍을 딕셔너리 a에 추가합니다. b는 딕셔너리거나 `PyMapping_Keys()`와 `PyObject_GetItem()`를 지원하는 모든 객체일 수 있습니다. override가 참이면, a에 있는 기존 쌍이 b에서 일치하는 키가 있으면 교체되고, 그렇지 않으면 a와 일치하는 키가 없을 때만 쌍이 추가됩니다. 성공하면 `0`을 반환하고, 예외가 발생하면 `-1`을 반환합니다.

int PyDict_Update( PyObject *a, PyObject *b)
  Part of the Stable ABI.

  이는 C에서 `PyDict_Merge(a, b, 1)`와 같고, 두 번째 인자에 “keys” 어트리뷰트가 없을 때 `PyDict_Update()`가 키-값 쌍의 시퀀스에 대해 이터레이트 하지 않는다는 점만 제외하면, 파이썬에서 `a.update(b)`와 유사합니다. 성공하면 `0`을 반환하고, 예외가 발생하면 `-1`을 반환합니다.

int PyDict_MergeFromSeq2( PyObject *a, PyObject *seq2, int override)
  Part of the Stable ABI.

  seq2의 키-값 쌍으로 딕셔너리 a를 갱신하거나 병합합니다. seq2는 키-값 쌍으로 간주하는 길이 2의 이터러블 객체를 생성하는 이터러블 객체여야 합니다. 중복 키가 있으면, override가 참이면 마지막이 승리하고, 그렇지 않으면 첫 번째가 승리합니다. 성공 시 `0`을 반환하고, 예외가 발생하면 `-1`을 반환합니다. 동등한 파이썬은 이렇습니다(반환 값 제외)

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

int PyDict_AddWatcher( PyDict_WatchCallback callback)

  Register callback as a dictionary watcher. Return a non-negative integer id which must be passed to future calls to `PyDict_Watch()`. In case of error (e.g. no more watcher IDs available), return `-1` and set an exception.

  Added in version 3.12.

int PyDict_ClearWatcher(int watcher_id)

  Clear watcher identified by watcher_id previously returned from `PyDict_AddWatcher()`. Return `0` on success, `-1` on error (e.g. if the given watcher_id was never registered.)

  Added in version 3.12.

int PyDict_Watch(int watcher_id, PyObject *dict)

  Mark dictionary dict as watched. The callback granted watcher_id by `PyDict_AddWatcher()` will be called when dict is modified or deallocated. Return `0` on success or `-1` on error.

  Added in version 3.12.

int PyDict_Unwatch(int watcher_id, PyObject *dict)

  Mark dictionary dict as no longer watched. The callback granted watcher_id by `PyDict_AddWatcher()` will no longer be called when dict is modified or deallocated. The dict must previously have been watched by this watcher. Return `0` on success or `-1` on error.

  Added in version 3.12.

type PyDict_WatchEvent

  Enumeration of possible dictionary watcher events: `PyDict_EVENT_ADDED`, `PyDict_EVENT_MODIFIED`, `PyDict_EVENT_DELETED`, `PyDict_EVENT_CLONED`, `PyDict_EVENT_CLEARED`, or `PyDict_EVENT_DEALLOCATED`.

  Added in version 3.12.

typedef int (*PyDict_WatchCallback)( PyDict_WatchEvent event, PyObject *dict, PyObject *key, PyObject *new_value)

  Type of a dict watcher callback function.

  If event is `PyDict_EVENT_CLEARED` or `PyDict_EVENT_DEALLOCATED`, both key and new_value will be `NULL`. If event is `PyDict_EVENT_ADDED` or `PyDict_EVENT_MODIFIED`, new_value will be the new value for key. If event is `PyDict_EVENT_DELETED`, key is being deleted from the dictionary and new_value will be `NULL`.

  `PyDict_EVENT_CLONED` occurs when dict was previously empty and another dict is merged into it. To maintain efficiency of this operation, per-key `PyDict_EVENT_ADDED` events are not issued in this case; instead a single `PyDict_EVENT_CLONED` is issued, and key will be the source dictionary.

  The callback may inspect but must not modify dict; doing so could have unpredictable effects, including infinite recursion. Do not trigger Python code execution in the callback, as it could modify the dict as a side effect.

  If event is `PyDict_EVENT_DEALLOCATED`, taking a new reference in the callback to the about-to-be-destroyed dictionary will resurrect it and prevent it from being freed at this time. When the resurrected object is destroyed later, any watcher callbacks active at that time will be called again.

  Callbacks occur before the notified modification to dict takes place, so the prior state of dict can be inspected.

  If the callback sets an exception, it must return `-1`; this exception will be printed as an unraisable exception using `PyErr_WriteUnraisable()`. Otherwise it should return `0`.

  There may already be a pending exception set on entry to the callback. In this case, the callback should return `0` with the same exception still set. This means the callback may not call any other API that can set an exception unless it saves and clears the exception state first, and restores it before returning.

  Added in version 3.12.