참조 횟수¶
The macros in this section are used for managing reference counts of Python objects.
-
void
Py_INCREF
(PyObject *o)¶ Indicate taking a new strong reference to object o, indicating it is in use and should not be destroyed.
This function is usually used to convert a borrowed reference to a strong reference in-place. The
Py_NewRef()
function can be used to create a new strong reference.When done using the object, release it by calling
Py_DECREF()
.객체는
NULL
일 수 없습니다;NULL
이 아닌지 확실하지 않으면,Py_XINCREF()
를 사용하십시오.Do not expect this function to actually modify o in any way.
-
void
Py_XINCREF
(PyObject *o)¶ Similar to
Py_INCREF()
, but the object o can beNULL
, in which case this has no effect.See also
Py_XNewRef()
.
-
PyObject *
Py_NewRef
(PyObject *o)¶ - Part of the Stable ABI since version 3.10.
Create a new strong reference to an object: call
Py_INCREF()
on o and return the object o.When the strong reference is no longer needed,
Py_DECREF()
should be called on it to release the reference.The object o must not be
NULL
; usePy_XNewRef()
if o can beNULL
.예를 들어:
Py_INCREF(obj); self->attr = obj;
can be written as:
self->attr = Py_NewRef(obj);
See also
Py_INCREF()
.버전 3.10에 추가.
-
PyObject *
Py_XNewRef
(PyObject *o)¶ - Part of the Stable ABI since version 3.10.
Similar to
Py_NewRef()
, but the object o can be NULL.If the object o is
NULL
, the function just returnsNULL
.버전 3.10에 추가.
-
void
Py_DECREF
(PyObject *o)¶ Release a strong reference to object o, indicating the reference is no longer used.
마지막 강한 참조가 해제되면 (즉 객체의 참조 횟수가 0이 되면), 객체 형의 할당 해제 함수 (반드시
NULL
이 아니어야 합니다)가 호출됩니다.This function is usually used to delete a strong reference before exiting its scope.
객체는
NULL
일 수 없습니다;NULL
이 아닌지 확실하지 않으면,Py_XDECREF()
를 사용하십시오.Do not expect this function to actually modify o in any way.
경고
The deallocation function can cause arbitrary Python code to be invoked (e.g. when a class instance with a
__del__()
method is deallocated). While exceptions in such code are not propagated, the executed code has free access to all Python global variables. This means that any object that is reachable from a global variable should be in a consistent state beforePy_DECREF()
is invoked. For example, code to delete an object from a list should copy a reference to the deleted object in a temporary variable, update the list data structure, and then callPy_DECREF()
for the temporary variable.
-
void
Py_XDECREF
(PyObject *o)¶ Similar to
Py_DECREF()
, but the object o can beNULL
, in which case this has no effect. The same warning fromPy_DECREF()
applies here as well.
-
void
Py_CLEAR
(PyObject *o)¶ 객체 o에 대한 강한 참조를 해제합니다. 객체는
NULL
일 수 있습니다, 이때 매크로는 효과가 없습니다; 그렇지 않으면 인자도NULL
로 설정된다는 점을 제외하고는, 효과가Py_DECREF()
와 같습니다. 매크로가 임시 변수를 신중하게 사용하고, 참조를 해제하기 전에 인자를NULL
로 설정하기 때문에,Py_DECREF()
에 대한 경고는 전달된 객체와 관련하여 적용되지 않습니다.가비지 수집 중에 탐색 될 수 있는 객체에 대한 참조를 해제할 때마다 이 매크로를 사용하는 것이 좋습니다.
-
void
Py_IncRef
(PyObject *o)¶ - Part of the Stable ABI.
Indicate taking a new strong reference to object o. A function version of
Py_XINCREF()
. It can be used for runtime dynamic embedding of Python.
-
void
Py_DecRef
(PyObject *o)¶ - Part of the Stable ABI.
Release a strong reference to object o. A function version of
Py_XDECREF()
. It can be used for runtime dynamic embedding of Python.
The following functions or macros are only for use within the interpreter core:
_Py_Dealloc()
, _Py_ForgetReference()
, _Py_NewReference()
,
as well as the global variable _Py_RefTotal
.