약한 참조 객체¶
파이썬은 약한 참조를 1급 객체로 지원합니다. 약한 참조를 직접 구현하는 두 가지 구체적인 객체 형이 있습니다. 첫 번째는 간단한 참조 객체이며, 두 번째는 가능한 한 원래 객체의 프락시 역할을 합니다.
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int PyWeakref_Check(PyObject *ob)¶
Return true if ob is either a reference or proxy object. This function always succeeds.
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int PyWeakref_CheckRef(PyObject *ob)¶
Return true if ob is a reference object. This function always succeeds.
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int PyWeakref_CheckProxy(PyObject *ob)¶
Return true if ob is a proxy object. This function always succeeds.
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PyObject *PyWeakref_NewRef(PyObject *ob, PyObject *callback)¶
- 반환값: 새 참조. Part of the 안정 ABI.
Return a weak reference object for the object ob. This will always return a new reference, but is not guaranteed to create a new object; an existing reference object may be returned. The second parameter, callback, can be a callable object that receives notification when ob is garbage collected; it should accept a single parameter, which will be the weak reference object itself. callback may also be
None
orNULL
. If ob is not a weakly referencable object, or if callback is not callable,None
, orNULL
, this will returnNULL
and raiseTypeError
.
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PyObject *PyWeakref_NewProxy(PyObject *ob, PyObject *callback)¶
- 반환값: 새 참조. Part of the 안정 ABI.
Return a weak reference proxy object for the object ob. This will always return a new reference, but is not guaranteed to create a new object; an existing proxy object may be returned. The second parameter, callback, can be a callable object that receives notification when ob is garbage collected; it should accept a single parameter, which will be the weak reference object itself. callback may also be
None
orNULL
. If ob is not a weakly referencable object, or if callback is not callable,None
, orNULL
, this will returnNULL
and raiseTypeError
.
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PyObject *PyWeakref_GetObject(PyObject *ref)¶
- 반환값: 빌린 참조. Part of the 안정 ABI.
Return the referenced object from a weak reference, ref. If the referent is no longer live, returns
Py_None
.참고
이 함수는 참조된 객체에 대한 빌린 참조를 반환합니다. 이는 빌린 참조의 마지막 사용 전에 파괴될 수 없을 때를 제외하고, 객체에 대해 항상
Py_INCREF()
를 호출해야 함을 뜻합니다.
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PyObject *PyWeakref_GET_OBJECT(PyObject *ref)¶
- 반환값: 빌린 참조.
PyWeakref_GetObject()
와 유사하지만, 에러 검사를 수행하지 않습니다.
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void PyObject_ClearWeakRefs(PyObject *object)¶
- Part of the 안정 ABI.
This function is called by the
tp_dealloc
handler to clear weak references.This iterates through the weak references for object and calls callbacks for those references which have one. It returns when all callbacks have been attempted.